Reportable Disease Trends in Ontario

Transcription

1 Reportable Disease Trends in Ontario 2013 Technical Report July 2015

2 Public Health Ontario Public Health Ontario is a Crown corporation dedicated to protecting and promoting the health of all Ontarians and reducing inequities in health. Public Health Ontario links public health practitioners, frontline health workers and researchers to the best scientific intelligence and knowledge from around the world. Public Health Ontario provides expert scientific and technical support to government, local public health units and health care providers relating to the following: communicable and infectious diseases infection prevention and control environmental and occupational health emergency preparedness health promotion, chronic disease and injury prevention public health laboratory services Public Health Ontario's work also includes surveillance, epidemiology, research, professional development and knowledge services. For more information, visit How to cite this document: Ontario Agency for Health Protection and Promotion (Public Health Ontario). Reportable disease trends in Ontario, Toronto, ON: Queen's Printer for Ontario; ISBN Public Health Ontario acknowledges the financial support of the Ontario Government. Queen s Printer for Ontario, 2015

3 Reportable Disease Trends in Ontario 2013

4 Contributing Authors The production of the Reportable Disease Trends in Ontario report was made possible by a collaboration of highly skilled and dedicated staff of the Communicable Diseases, Emergency Preparedness and Respose department at Public Health Ontario (PHO). Production of the report was led by Surveillance Services, with contributions from: the Communicable Diseases unit; the Enteric, Zoonotic and Vector-borne Diseases unit; and the Immunization and Vaccine-Preventable Diseases unit. Acknowledgements Surveillance Services wishes to express their sincere appreciation for the effort and dedication demonstrated by Ontario s 36 public health units in collecting and reporting data on reportable diseases. We also thank our PHO colleagues from the Communicable Diseases, Emergency Preparedness and Respose department, Analytic Services, Communications, Library Services, and Public Health Ontario Laboratories for their collaboration in the development, review, and interpretation of the reportable disease trends presented here. July 2015 Disclaimer This document was developed by Public Health Ontario (PHO). PHO provides scientific and technical advice to Ontario s government, public health organizations and health care providers. PHO s work is guided by the current best available evidence. PHO assumes no responsibility for the results of the use of this document by anyone. This document may be reproduced without permission for non-commercial purposes only and provided that appropriate credit is given to Public Health Ontario. No changes and/or modification may be made to this document without explicit written permission from Public Health Ontario. Reportable Disease Trends in Ontario, 2013 iv

5 Contents List of Figures... vii List of Tables... x List of Maps... x Report introduction... 1 About this report... 2 List of acronyms... 3 Ontario s public health units and regions... 4 Chapter Acquired Immunodeficiency Syndrome and Human Immunodeficiency Virus Infection... 6 Chapter Acute Flaccid Paralysis (AFP) Chapter Amebiasis Chapter Anthrax Chapter Botulism Chapter Brucellosis Chapter Campylobacter enteritis Chapter Chancroid Chapter Chlamydia Chapter Cholera Chapter Clostridium difficile Infection (CDI) Outbreaks Chapter Cryptosporidiosis Chapter Cyclosporiasis Chapter Cytomegalovirus Infection, Congenital Reportable Disease Trends in Ontario, 2013 Chapter Diphtheria Chapter Giardiasis Chapter Gonorrhea Chapter Group A Streptococcal Disease, Invasive (igas) Chapter Group B Streptococcal Disease, Neonatal Chapter Hantavirus Pulmonary Syndrome Chapter Hemorrhagic Fevers Chapter Hepatitis A Chapter Hepatitis B Chapter Hepatitis C Chapter Hepatitis D Chapter Herpes, Neonatal Chapter Influenza Chapter Invasive Haemophilus influenzae, type b Chapter Lassa Fever Chapter Legionellosis Chapter Leprosy Chapter Listeriosis v

6 Chapter Lyme Disease Chapter Malaria Chapter Measles Chapter Meningococcal Disease, Invasive Chapter Mumps Chapter Ophthalmia Neonatorum Chapter Paralytic Shellfish Poisoning Chapter Paratyphoid Fever Chapter Pertussis Chapter Plague Chapter Streptococcus pneumoniae, Invasive Chapter Poliomyelitis (polio) Chapter Psittacosis/Ornithosis Chapter Q Fever Chapter Rabies Chapter Rubella and Congenital Rubella Syndrome Chapter Salmonellosis Chapter Shigellosis Chapter Smallpox Chapter Syphilis, Infectious Chapter Tetanus Chapter Transmissible Spongiform Encephalopathy Chapter Trichinosis Chapter Tuberculosis Chapter Tularemia Chapter Typhoid Fever Chapter Varicella (Chickenpox) Chapter Verotoxin-producing E. coli infection indicator conditions, including Hemolytic Uremic Syndrome Chapter West Nile Virus Illness Chapter Yellow Fever Chapter Yersiniosis References Appendices Appendix Technical notes Appendix Reportable diseases and reportable classifications: Ontario, Reportable Disease Trends in Ontario, 2013 vi

7 List of Figures Figure 1-1. Incidence of HIV: Ontario and Canada, Figure 1-2. Incidence of HIV by age and sex: Ontario, Figure 1-3. Incidence of AIDS: Ontario and Canada, Figure 1-4. Incidence of AIDS by age and sex: Ontario, Figure 3-1. Incidence of confirmed and probable amebiasis: Ontario, Figure 3-2. Incidence of confirmed and probable amebiasis by age and sex: Ontario, Figure 3-3. Number of confirmed and probable amebiasis cases by month: Ontario, Figure 5-1. Incidence of botulism: Ontario and Canada, Figure 6-1. Incidence of brucellosis: Ontario and Canada, Figure 7-1. Incidence of Campylobacter enteritis: Ontario and Canada, Figure 7-2. Incidence of Campylobacter enteritis by age and sex: Ontario, Figure 7-3. Number of Campylobacter enteritis cases by month: Ontario, Figure 9-1. Incidence of chlamydia: Ontario and Canada, Figure 9-2. Incidence of chlamydia by age and sex: Ontario, Figure 9-3. Number and per cent of positive chlamydia tests by month: PHOL, Figure Incidence of cholera: Ontario and Canada, Figure Number of CDI cases associated with a hospital outbreak by sex and age group: Ontario, Figure Number of confirmed CDI outbreaks in 2013 and average number of CDI outbreaks from by month: Ontario Figure Incidence of cryptosporidiosis: Ontario and Canada, Reportable Disease Trends in Ontario, 2013 Figure Incidence of cryptosporidiosis by age and sex: Ontario, Figure Number of cryptosporidiosis cases by month: Ontario, Figure Incidence of cyclosporiasis: Ontario and Canada, Figure Incidence of cyclosporiasis by age and sex: Ontario, Figure Number of cyclosporiasis cases by month: Ontario, Figure Incidence of giardiasis: Ontario and Canada, Figure Incidence of giardiasis by age and sex: Ontario, Figure Number of giardiasis cases by month: Ontario, Figure Incidence of gonorrhea: Ontario and Canada, Figure Incidence of gonorrhea by age and sex: Ontario, Figure Number and per cent of positive gonorrhea tests by month: Ontario, Figure Incidence of group A streptococcal disease, invasive (igas): Ontario and Canada, Figure Incidence of group A streptococcal disease, invasive (igas) by age and sex: Ontario, Figure Number of group A streptococcal disease, invasive (igas) cases by month: Ontario, Figure Incidence of group B streptococcal disease, neonatal: Ontario and Canada, Figure Incidence of hepatitis A: Ontario and Canada, Figure Incidence of hepatitis A by age and sex: Ontario, Figure Number of hepatitis A cases by month: Ontario, Figure Incidence of hepatitis B (acute): Ontario, Figure Incidence of hepatitis B (acute) by age and sex: Ontario, vii

8 Figure Incidence of hepatitis B (chronic) by age and sex: Ontario, Figure Incidence of hepatitis C: Ontario and Canada, Figure Incidence of hepatitis C by age and sex: Ontario, Figure Incidence of hepatitis D: Ontario, Figure Incidence of laboratory-confirmed influenza: Ontario, to seasons Figure Incidence of laboratory-confirmed influenza by age and sex: Ontario, season. 79 Figure Number of laboratory-confirmed influenza cases by month: Ontario, season Figure Number of influenza tests and per cent of positive tests by specimen collection week: Ontario, season Figure Incidence of Haemophilus influenzae, type b: Ontario and Canada, Figure Incidence of Haemophilus influenzae, type b by age: Ontario, Figure Incidence of legionellosis: Ontario and Canada, Figure Incidence of legionellosis by age and sex: Ontario, Figure Number of legionellosis cases by month: Ontario, Figure Number of patients tested and per cent positivity for Legionella by test month: Ontario, Figure Incidence of listeriosis: Ontario and Canada, Figure Incidence of listeriosis by age and sex: Ontario, Figure Number of listeriosis cases by month: Ontario, Figure Incidence of confirmed and probable Lyme disease: Ontario and Canada, Figure Incidence of confirmed and probable Lyme disease by age and sex: Ontario, Figure Number of confirmed and probable Lyme disease cases by month: Ontario, Figure Incidence of malaria: Ontario and Canada, Figure Incidence of malaria by age and sex: Ontario, Figure Number of malaria cases by month: Ontario, Figure Incidence of measles: Ontario and Canada, Figure Incidence of measles by age: Ontario, Figure Incidence of invasive meningococcal disease: Ontario and Canada, Figure Incidence of invasive meningococcal disease by serogroup*: Ontario, Figure Incidence of invasive meningococcal disease by age: Ontario, Figure Incidence of mumps: Ontario and Canada, Figure Incidence of mumps by outbreak status: Ontario, Figure Incidence of mumps by age and sex: Ontario, Figure Incidence of paratyphoid fever: Ontario, Figure Incidence of paratyphoid fever by age and sex: Ontario, Figure Number of paratyphoid fever cases by month: Ontario, Figure Incidence of pertussis: Ontario and Canada, Figure Number of pertussis cases by month: Ontario, Figure Incidence of pertussis by age and sex: Ontario, Figure Incidence of invasive pneumococcal disease: Ontario and Canada, Figure Incidence of invasive pneumococcal disease by age and sex: Ontario, Figure Number of invasive pneumococcal disease cases by month: Ontario, Reportable Disease Trends in Ontario, 2013 viii

9 Figure Invasive pneumococcal disease incidence by age group and vaccine serotype (ST) Group: Ontario, Figure Incidence of Q fever: Ontario, Figure Incidence of rubella: Ontario and Canada, Figure Incidence of congenital rubella syndrome: Ontario and Canada, Figure Incidence of salmonellosis: Ontario and Canada, Figure Incidence of salmonellosis by age and sex: Ontario, Figure Number of salmonellosis cases by month: Ontario, Figure Incidence of shigellosis: Ontario and Canada, Figure Incidence of shigellosis by age and sex: Ontario, Figure Number of shigellosis cases by month: Ontario, Figure Incidence of syphilis, infectious: Ontario, Figure Incidence of syphilis, infectious by age and sex: Ontario, Figure Incidence of tetanus: Ontario and Canada, Figure Incidence of tuberculosis: Ontario and Canada, Figure Incidence of tuberculosis by age and sex: Ontario, Figure Incidence of typhoid fever: Ontario and Canada, Figure Incidence of typhoid fever by age and sex: Ontario, Figure Number of typhoid fever cases by month: Ontario, Figure Incidence of aggregate varicella (chickenpox): Ontario and Canada, Figure Incidence of aggregate varicella (chickenpox) by age group: Ontario, Figure Incidence of aggregate varicella (chickenpox) by month: Ontario, Figure Incidence of VTEC: Ontario and Canada, Figure Incidence of VTEC by age and sex: Ontario, Figure Number of VTEC cases by month: Ontario, Figure Incidence of Confirmed and Probable West Nile Virus Illness: Ontario and Canada, Figure Incidence of West Nile Virus Illness by age and sex: Ontario, Figure Number of West Nile Virus Illness cases by month: Ontario, Figure Incidence of yersiniosis: Ontario, Figure Incidence of yersiniosis by age and sex: Ontario, Figure Number of yersiniosis cases by month: Ontario, Reportable Disease Trends in Ontario, 2013 ix

10 List of Tables Table Number of cases linked to CDI outbreaks and all-cause mortality: Ontario, Table Risk factors for confirmed CDI cases associated with a hospital outbreak: Ontario, 2013 (n=134) Table Incidence of congenital cytomegalovirus infection: Ontario, Table Cases of group A streptococcal disease, invasive (igas) by emm type: Ontario, Table Incidence of herpes, neonatal: Ontario, Table Laboratory-confirmed influenza cases by type: Ontario, season List of Maps Map 1-1. Incidence of HIV by public health unit of residence: Ontario, Map 1-2. Incidence of AIDS by public health unit of residence: Ontario, Map 3-1. Incidence of confirmed and probable amebiasis by public health unit of residence: Ontario, Map 7-1. Incidence of Campylobacter enteritis by public health unit of residence: Ontario, Map 9-1. Incidence of chlamydia by public health unit of residence: Ontario, Map Number of CDI outbreaks by public health unit: Ontario, Map Incidence of cryptosporidiosis by public health unit of residence: Ontario, Map Incidence of cyclosporiasis by public health unit of residence: Ontario, Map Incidence of giardiasis by public health unit of residence: Ontario, Map Incidence of gonorrhea by public health unit of residence: Ontario, Table Incidence of leprosy: Ontario and Canada, Table Malaria cases by Plasmodium species: Ontario, Table Genotype distribution of measles cases: Ontario, Table Incidence of ophthalmia neonatorum: Ontario, Table Salmonellosis cases by Salmonella serotype: Ontario, Table Shigellosis cases by Shigella serotype: Ontario, Table Tuberculosis cases by country of birth: Ontario, Map Incidence of group A streptococcal disease, invasive (igas) by public health unit of residence: Ontario, Map Incidence of group B streptococcal disease, neonatal by public health unit of residence: Ontario, Map Incidence of hepatitis A by public health unit of residence: Ontario, Map Incidence of hepatitis B (acute) by public health unit of residence: Ontario, Map Incidence of hepatitis B (chronic) by public health unit of residence: Ontario, Map Incidence of hepatitis C by public health unit of residence: Ontario, Map Incidence of laboratory-confirmed influenza by public health unit of residence: Ontario, season Map Incidence of legionellosis by public health unit of residence: Ontario, Map Incidence of listeriosis by public health unit of residence: Ontario, Reportable Disease Trends in Ontario, 2013 x

11 Map Incidence of confirmed and probable Lyme disease by public health unit of residence: Ontario, Map Incidence of malaria by public health unit of residence: Ontario, Map Incidence of measles by public health unit of residence: Ontario, Map Incidence of invasive meningococcal disease by public health unit of residence: Ontario, Map Incidence of mumps by public health unit of residence: Ontario, Map Incidence of paratyphoid fever by public health unit of residence: Ontario, Map Incidence of pertussis by public health unit of residence: Ontario, Map Incidence of invasive pneumococcal disease by public health unit of residence: Ontario, Map Incidence of salmonellosis by public health unit of residence: Ontario, Map Incidence of shigellosis by public health unit of residence: Ontario, Map Incidence of syphilis, infectious by public health unit of residence: Ontario, Map Incidence of tuberculosis by public health unit of residence: Ontario, Map Incidence of typhoid fever by public health unit of residence: Ontario, Map Incidence of aggregate varicella (chickenpox) by public health unit of residence: Ontario, Map Incidence of VTEC by public health unit of residence: Ontario, Map Incidence of West Nile Virus Illness by public health unit of residence: Ontario, Map Incidence of yersiniosis by public health unit of residence: Ontario, Reportable Disease Trends in Ontario, 2013 xi

12 Report introduction Reportable Disease Trends in Ontario,

13 About this report The 2013 Reportable Disease Trends in Ontario report contributes to the provincial infectious diseases surveillance system, serving as an outlet for the dissemination of information on reportable disease epidemiology in Ontario. The objectives of this report are: To summarize infectious diseases in Ontario in 2013, and where applicable, compare to historical trends. To describe the epidemiology of infectious diseases in Ontario for a public health audience, specifically public health units (PHUs) and the Ministry of Health and Long-Term Care (MOHLTC), using various surveillance data sources available to PHO. The scope of this report is limited to reportable diseases under Regulation 559/91 pursuant to the Health Protection and Promotion Act (HPPA), R.S.O This report provides a brief descriptive analysis of the reportable diseases with a focus on 2013 cases, along with brief commentary, interpretation, and references to other related PHO products. Reportable disease chapters are presented in alphabetical order. Data in this report may differ from previously published or future reports, as iphis is a dynamic disease reporting system that allows ongoing updates to data previously entered. As a result, data extracted from iphis represent a snapshot at the time of extraction and may differ from previous or subsequent reports. Discrepancies in disease counts and rates provided in this report and other published data may exist due to: Enhanced data cleaning for this report for select analyses, such as the linkage of iphis and laboratory data and subsequent reconciliation in iphis Late reporting Local and/or provincial-led data cleaning initiatives Differences in data extraction dates. Where such variability exists, data provided in other PHO surveillance products (e.g., Monthly Infectious Diseases Surveillance Report) or published research may be more appropriate sources depending on how the methodology, data caveats, and/or extraction dates align with the intended use of the data. For more information on the data used for this report, please refer to Appendix 1: Technical notes. The 2013 report is also available in an interactive format, which provides quick, at-a-glance highlights of the full content presented in this document. Both versions of the report are available on PHO s website. We welcome your comments and suggestions regarding the 2013 report to help us make future editions more useful to you. Please contact Surveillance Services at SurveillanceServices@oahpp.ca. Reportable Disease Trends in Ontario,

14 List of acronyms AEFI Adverse Events Following Immunization AFP Acute Flaccid Paralysis AIDS Acquired Immunodeficiency Syndrome CDI Clostridium difficile infection CFA Complete-for-age CFA-not VP Complete-for-age, not vaccinepreventable CFA-VF Complete-for-age, vaccine failure CJD Creutzfeldt-Jakob disease CJDSS Canadian CJD Surveillance System CMV Cytomegalovirus CRS Congenital rubella syndrome DHU Diagnosing health unit ESD Enhanced Surveillance Directive FFI Fatal Familial Insomnia GBS Group B streptococcal disease (neonatal) GSS Gerstmann-Sträussler-Scheinker Syndrome Hib Haemophilus influenzae type B HIV Human Immunodeficiency Virus HPPA Health Protection and Promotion Act HUS Haemolytic uremic syndrome igas Invasive group A streptococcal disease IMD Invasive meningococcal disease IPD Invasive pneumococcal disease iphis integrated Public Health Information System IPV Inactivated polio vaccine LIMS Laboratory Information Management System MCC Meningococcal C conjugate vaccine MCV4 Meningococcal conjugated vaccine MDR-TB Multidrug-resistant tuberculosis (TB) MMR vaccine Measles, mumps, rubella vaccine MMRV vaccine Measles, mumps, rubella, varicella vaccine MOHLTC Ministry of Health and Long-Term Care MSM Men who have sex with men NAAT Nucleic acid amplification testing NAP1 North American Pulsed Field type 1 (C. difficile strain) NML National Microbiology Laboratory OICC Outbreak Investigation Coordination Committee ON-OICC Ontario Outbreak Investigation Coordination Committee ONBOIDS Ontario Burden of Infectious Disease Study OUT-TB Ontario Universal Typing of Tuberculosis PCR Polymerase chain reaction PCV Pneumococcal conjugate vaccine PHAC Public Health Agency of Canada PAHO Pan American Health Organization PHO Public Health Ontario PHOL Public Health Ontario Laboratories PHU Public health unit PPV Pneumococcal polysaccharide vaccine RDIS Reportable Diseases Information System RSV Respiratory syncytial virus SARS Severe acute respiratory syndrome STEC Shiga toxin-producing E. coli STI Sexually transmitted infections TB Tuberculosis VHFs Viral hemorrhagic fevers VTEC Verotoxin-producing E. coli infections WHO World Health Organization WNV West Nile Virus XDR-TB Extensively drug-resistant tuberculosis (TB) Reportable Disease Trends in Ontario,

15 Ontario s public health units and regions As depicted in the map below, there are 36 public health units (PHUs) in Ontario, which are grouped into health regions. The table on the following page also provides a reference to PHU abbreviations used in this report. Reportable Disease Trends in Ontario,

16 Public health units and regions Public Health Units and Regions Abbreviation Public Health Units and Regions Abbreviation NORTH WEST TORONTO Thunder Bay District THB Toronto TOR Northwestern NWR SOUTH WEST NORTH EAST Chatham-Kent CHK Algoma North Bay Parry Sound District Porcupine Sudbury & District Timiskaming EASTERN Eastern Ontario City of Ottawa Hastings & Prince Edward Counties Kingston, Frontenac and Lennox & Addington Leeds, Grenville and Lanark District Renfrew County and District CENTRAL EAST ALG NPS PQP SUD TSK EOH OTT HPE KFL LGL REN Elgin-St. Thomas Grey Bruce Huron County Lambton County Middlesex-London Oxford County Perth District Windsor-Essex County CENTRAL WEST Brant County City Of Hamilton Haldimand-Norfolk Halton Region Niagara Region Waterloo Region ELG GBO HUR LAM MSL OXF PDH WEC BRN HAM HDN HAL NIA WAT Durham Region DUR Wellington-Dufferin-Guelph WDG Haliburton, Kawartha, Pine Ridge Peel Region Peterborough County-City Simcoe Muskoka District HKP PEE PTC SMD York Region YRK Reportable Disease Trends in Ontario,

17 Chapter 1. Acquired Immunodeficiency Syndrome and Human Immunodeficiency Virus Infection General overview for 2013: Human Immunodeficiency Virus (HIV) Incidence and comparison to Canada (Figure 1-1): In 2013, 706 cases of HIV were reported in Ontario, corresponding to an incidence rate of 5.2 cases per 100,000 population. The incidence rate of HIV was relatively stable from , at around 8.0 cases per 100,000 population, before decreasing between 2006 and 2013, with a low of 5.2 cases per 100,000 population reported in Provincial incidence rates varied in terms of the rates for the rest of Canada from Age and sex (Figure 1-2): In 2013, males accounted for 82.6% (583/706) of reported HIV cases in Ontario. The incidence rate of HIV among males (8.8 cases per 100,000 population) in 2013 was more than five times higher than the incidence rate among females (1.7 cases per 100,000 population) (data not shown). Overall, cases ranged from less than 1 to 77 years of age. Among males, the incidence of HIV was highest among those in the year age group. The incidence of HIV among males remains high in the and year age groups; among females, the incidence was highest among those in the year age group. Geographic distribution (Map 1-1): Cases of HIV were reported in 30 public health units, with 56.7% of cases (400/706) reported in Toronto. The public health units reporting the highest incidence rates of HIV in Ontario in 2013 were Toronto, Chatham-Kent, and Windsor- Essex County, with 14.4, 6.6, and 6.5 cases per 100,000 population, respectively. Deaths: Sixteen cases of the HIV cases reported in 2013 were fatal; however, six of these cases were not recorded in iphis as having Acquired Immunodeficiency Syndrome (AIDS). It is possible that these cases had an AIDS indicative disease and that this information was not captured in iphis. Additional methodological issues There are several challenges associated with HIV surveillance. The annual incidence of HIV is made up of cases that are reported to public health units in Ontario during the year. This does not reflect when individuals acquired their HIV infection, which likely occurred considerably earlier, with the cases not previously diagnosed. Anonymous testing for HIV also presents challenges for surveillance. HIV rates may be underestimated because anonymous test results are not always consistently entered in iphis. On the other hand, HIV rates may be overestimated in some jurisdictions when individuals travel outside their public health unit of residence to seek anonymous testing, with the case being reported in the health unit jurisdiction providing the anonymous testing. Duplication may occur when nominal confirmatory tests are entered in iphis for cases previously entered based on anonymous test results. If an HIV case is reported in a given year and progresses to/is diagnosed with AIDS in the same year, that person will be counted in both the HIV and AIDS case counts. Consequently, counts of HIV and AIDS are not mutually exclusive in this report and cannot be combined. If a death takes place after health units have completed follow-up of an HIV case, the information may not be reported to the health unit, resulting in the death not being recorded in iphis. Therefore data on HIV deaths as reported in iphis may not reflect the true counts. Reportable Disease Trends in Ontario

18 Additional sources of information For more information about HIV/AIDS in Ontario, additional data and reports are available from the Ontario HIV Epidemiologic Monitoring Unit at the Dalla Lana School of Public Health, University of Toronto and the Ontario HIV Treatment Network. Reportable Disease Trends in Ontario

19 Figure 1-1. Incidence of HIV: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure 1-2. Incidence of HIV by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes three cases of unknown age and/or sex. Reportable Disease Trends in Ontario,

20 Map 1-1. Incidence of HIV by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

21 General overview for 2013: Acquired Immunodeficiency Syndrome (AIDS) Incidence and comparison to Canada (Figure 1-3): In 2013, there were 100 newly diagnosed cases of AIDS reported in Ontario, corresponding to an incidence rate of 0.7 cases per 100,000 population. Despite a degree of annual variability, the overall incidence rate of reported AIDS cases decreased between 2004 and 2013; a high of 1.8 cases per 100,000 population was reported in 2005 and a low of 0.6 cases per 100,000 population was reported in In 2013, 82.0% (82/100) of AIDS cases had their HIV diagnosis reported to public health in 2013, after, or less than 30 days prior to, being diagnosed with AIDS (data not shown). These data suggest that a substantial proportion of AIDS cases may not have had previous knowledge of their HIV infection, and that the infection had progressed to the point where the person was diagnosed with an AIDS indicative disease. Some of these cases, however, may have been screened for HIV anonymously or outside Ontario prior to Age and sex (Figure 1-4): In 2013, males accounted for 79.0% (79/100) of reported AIDS cases in Ontario; the remaining cases occurred in females, with the exception of one case in a transgendered individual (not included in data for Figure 1-4). The incidence rate among males (1.2 cases per 100,000 population) was four times higher than the incidence rate among females (0.3 cases per 100,000 population) (data not shown). Reported cases of AIDS ranged from 18 to 77 years. The incidence rate of AIDS was highest among males in the year age group, with the incidence among males and remaining high. For females, the rates were highest in the and year age groups. Geographic distribution (Map 1-2): In 2013, newlydiagnosed cases of AIDS were reported in 23 of Ontario s public health units, with the largest proportion of cases (39.0%, 39/100) reported in Toronto. The highest incidence rates were reported by Elgin-St. Thomas, Northwestern, and Huron County public health units, with 4.4, 3.7, and 1.7 cases per 100,000 population, respectively. The high rates observed in these public health units may be the result of low case counts in jurisdictions with relatively small populations. Hospitalizations and deaths: Fourteen cases diagnosed with AIDS in Ontario in 2013 were reported as fatal. Additional methodological issues The number of AIDS cases reported to public health units is likely an underestimate of the true incidence of AIDS in a given year. With the widespread use of effective and well-tolerated anti-retroviral therapies and effective treatments for AIDS indicative diseases, AIDSrelated complications such as multiple/recurrent bacterial infections, esophageal candidiasis, chronic herpes simplex, Kaposi s sarcoma, and others can be successfully treated. 1 Although these AIDS indicative diseases historically may have been diagnosed in the later stages of HIV infection, ultimately leading to death, they currently may be successfully treated before the HIV-infected person is reported as an AIDS case to a public health unit. In addition, there may be a perception among clinicians that some of these AIDS indicative diseases, in light of current and effective therapies, are not always indicative of disease progression to AIDS. If death due to AIDS occurs after a public health unit has completed follow-up with the case, the death may not be reported to the public health unit or recorded in iphis. Additional sources of information For more information about HIV/AIDS in Ontario, additional data and reports are available from the Ontario HIV Epidemiologic Monitoring Unit at the Dalla Lana School of Public Health, University of Toronto and the Ontario HIV Treatment Network. Reportable Disease Trends in Ontario,

22 Figure 1-3. Incidence of AIDS: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Quebec did not report AIDS cases to PHAC from and Newfoundland did not report AIDS cases to PHAC from ; the populations of these provinces were removed prior to national rate calculation for the years they did not report. Figure 1-4. Incidence of AIDS by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes one transgender case. Reportable Disease Trends in Ontario,

23 Map 1-2. Incidence of AIDS by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

24 Chapter 2. Acute Flaccid Paralysis (AFP) General overview for 2013 On December 4, 2013, AFP was added to the Ontario Reportable Diseases List. Despite not being reportable for all of 2013, a chapter on AFP surveillance is included to increase awareness about the reportability of this condition. AFP surveillance and case investigation are essential to rule out poliovirus as a causative agent of AFP, and to maintain Canada s polio-free certification status. AFP has been nationally notifiable in Canada since Incidence and comparison to Canada: There were no cases of AFP reported in Ontario in December Between 2004 and 2012, Canadian incidence rates ranged between 0.6 and 1.0 cases per 100,000 population under 15 years of age. 3 No comparable provincial data are available since AFP was not provincially reportable until December The World Health Organization has estimated that approximately one case of AFP is expected annually per 100,000 population under the age of 15 years. 4 Based on this estimate and the population of Ontario, approximately 22 cases of AFP among children under 15 years of age would be expected in Ontario every year. Reportable Disease Trends in Ontario,

25 Chapter 3. Amebiasis General overview for 2013 Incidence and comparison to Canada (Figure 3-1): Amebiasis is caused by the parasite Entamoeba histolytica. In 2013, there were 123 confirmed cases and 698 probable cases of amebiasis reported in Ontario, representing a combined incidence rate of 6.1 cases per 100,000 population. No comparable national data are available as amebiasis is not a nationally notifiable disease. Age and sex (Figure 3-2): The highest incidence rates were observed in the to year age groups. Amebiasis is known to be a disease mostly affecting young to middle-aged adults. Rates were higher in males than in females. Seasonal trends (Figure 3-3): Amebiasis is reported throughout the year with no notable seasonal trends. Additional methodological issues In early 2009, the provincial case definition was revised to include both confirmed and probable cases to reflect laboratory testing practices in Ontario. While this change did not have an impact on the total number of cases reported annually, the number of confirmed cases has been lower than the number of probable cases reported in each subsequent year. In addition, the change in case definition may have resulted in misclassification of cases in the first two years after the revision. To differentiate between E. histolytica and E. dispar (the non-pathogenic organism of the same genus) and be considered a confirmed case of E. histolytica, a follow-up specimen is required prior to treatment initiation. These specimens are rarely collected for submission, resulting in a higher proportion of probable cases than confirmed cases. Geographic distribution (Map 3-1): The highest incidence rates were reported by Toronto (14.4 cases per 100,000 population) and Peel Region (9.8 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 0.7 % (6/821) of cases and no deaths were reported. Reportable Disease Trends in Ontario,

26 Figure 3-1. Incidence of confirmed and probable amebiasis: Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure 3-2. Incidence of confirmed and probable amebiasis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

27 Figure 3-3. Number of confirmed and probable amebiasis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

28 Map 3-1. Incidence of confirmed and probable amebiasis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

29 Chapter 4. Anthrax General overview for 2013 There were no cases of anthrax reported in Ontario in No human cases of anthrax have been reported in Ontario since electronic reporting began in Reportable Disease Trends in Ontario,

30 Chapter 5. Botulism General overview for 2013 No cases of botulism were reported in Ontario in Since 2004, there have been 28 cases reported in the province. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, April 2013 edition The Ministry of Health and Long-Term Care s Botulism guide for health care professionals, September 2013 Walton R, Alexander C, Jackson C, Stephen M,Wharton D, Haydu L, et al. Outbreak of Type E foodborne botulism linked to traditionally prepared salted fish in Ontario, Canada. Foodborne Pathog Dis. 2014;11(10): Figure 5-1. Incidence of botulism: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

31 Chapter 6. Brucellosis General overview for 2013 Incidence and comparison to Canada (Figure 6-1): In Ontario in 2013, 10 confirmed cases of brucellosis were reported, corresponding to an incidence rate of 0.7 cases per 1,000,000 population. Hospitalizations and deaths: Hospitalization was reported for 50.0% (5/10) of cases. No deaths were reported. Highlights There is a low endemic risk of brucellosis in Ontario because reported cases are generally travel-related. Brucellosis has been eradicated from livestock in Canada since Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, May 2013 edition Figure 6-1. Incidence of brucellosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

32 Chapter 7. Campylobacter enteritis General overview for 2013 Incidence and comparison to Canada (Figure 7-1): In Ontario in 2013, there were 3,940 confirmed cases of Campylobacter enteritis, representing an incidence rate of 29.1 cases per 100,000 population. From 2004 to 2012, the annual incidence rates for Campylobacter enteritis in Ontario have been comparable to the Canadian rates. Hospitalizations and deaths: Hospitalization was reported for 5.6 % (221/3,940) of cases, and death was reported for 0.1 % (3/3,940) of cases. Age and sex (Figure 7-2): The highest incidence rates of Campylobacter enteritis were observed among the year age group (38.6 cases per 100,000 population), followed by the 0 4 year age group (36.6 cases per 100,000 population). Incidence rates were higher in males compared to females across all age groups. These age-and gender-specific trends have also been observed in other jurisdictions. 6 Seasonal trends (Figure 7-3): Campylobacter enteritis occurs throughout the year, but tends to follow a seasonal pattern, with increased incidence in the warmer months from June to October. Geographic distribution (Map 7-1): The highest incidence rates were reported in Huron County (65.0 cases per 100,000 population), Perth District (56.5 cases per 100,000 population), and Grey Bruce (51.6 cases per 100,000). These public health unit jurisdictions include rural farming communities where contact with animals and their environments, a key route of transmission for Campylobacter enteritis, is more likely. 7 In contrast, due to larger populations, the highest numbers of cases were reported in Toronto (1,018 cases), York Region (381 cases), and Peel Region (369 cases), representing 44.9% (1,768/3,940) of Campylobacter enteritis cases in Reportable Disease Trends in Ontario,

33 Figure 7-1. Incidence of Campylobacter enteritis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure 7-2. Incidence of Campylobacter enteritis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

34 Figure 7-3. Number of Campylobacter enteritis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

35 Map 7-1. Incidence of Campylobacter enteritis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

36 Chapter 8. Chancroid General overview for 2013 Incidence and comparison to Canada: Chancroid is a very rare disease in Canada. As of the end of 2013, the most recent case in Ontario was reported in 1997 and was the only case reported in that year. Reportable Disease Trends in Ontario,

37 Chapter 9. Chlamydia General overview for 2013 Incidence and comparison to Canada (Figure 9-1): Chlamydia is the most frequently reported sexually transmitted infection (STI) and reportable disease in Ontario. In 2013, 34,614 confirmed cases of chlamydia were reported in Ontario, an incidence rate of cases per 100,000 population. From 2004 to 2013, chlamydia incidence rates increased from cases per 100,000 population in 2004 to cases per 100,000 population in 2011, with subsequent decreases in 2012 and Chlamydia incidence rates in Ontario have been consistently lower than those in the rest of Canada. Age and sex (Figure 9-2): The reported incidence of chlamydia was considerably higher among females overall; there were almost two female cases for every male case (61.5% of cases were female; 21,280/34,598) with an incidence rate of female cases per 100,000 population, compared to male cases per 100,000 population (data not shown). The reported incidence of chlamydia was highest among those years of age in both males and females, with rates of and 1,751.2 cases per 100,000 population, respectively. However, the rates for both sexes decreased with increasing age, following their peaks in the year age groups. which may indicate continued transmission at similar levels. However, testing for chlamydia is also completed at private laboratories throughout the province, which constitutes the majority of chlamydia testing in Ontario; therefore, trends based on PHOL data should be interpreted with this context. Geographic distribution (Map 9-1): Incidence rates of reported chlamydia cases were highest in the North West region. Northwestern public health unit had the highest rate at cases per 100,000 population, followed by Porcupine and Thunder Bay District public health units, with rates of and cases per 100,000 population, respectively. Additional methodological issues Cases of chlamydia are often undetected and as a result, are under-reported to public health units due to the occurrence of asymptomatic infections. Despite the absence of symptoms, those infected are still able to transmit chlamydia to their sexual contacts. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, July 2012 edition Laboratory data (Figure 9-3): Based on testing performed at Public Health Ontario Laboratories (PHOL), the percentage of nucleic acid amplification tests (NAAT) that were positive for chlamydia each month in 2013 was relatively steady, with an overall per cent positivity of 6.0% (16,234/269,530) for the year. There were fewer NAAT tests for chlamydia performed at PHOL in 2013 than in 2011 or 2012 (269,530 versus 289,472 and 288,452 respectively). Despite decreases in tests performed, the per cent positivity has remained similar, Reportable Disease Trends in Ontario,

38 Figure 9-1. Incidence of chlamydia: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure 9-2. Incidence of chlamydia by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes 22 cases of unknown age and/or sex. Reportable Disease Trends in Ontario,

39 Figure 9-3. Number and per cent of positive chlamydia tests by month: PHOL, 2013 Ontario Cases: Public Health Ontario Laboratories (PHOL), STI Online, extracted [2014/11/14]. Note: Data only include tests performed at PHOL. Reportable Disease Trends in Ontario,

40 Map 9-1. Incidence of chlamydia by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

41 Chapter 10. Cholera General overview for 2013 There were no cases of cholera reported in Ontario in Since 2004, seven cases have been reported in the province. All seven cases were travel-related. Figure Incidence of cholera: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

42 Chapter 11. Clostridium difficile Infection (CDI) Outbreaks General overview for 2013 Incidence (Table 11-1): In 2013, a total of 166 confirmed cases associated with 30 CDI outbreaks were reported in Ontario. Eighty-three per cent (n=25) of all reported CDI outbreaks in 2013 occurred in hospitals, with the remainder occurring in long-term care facilities. Although the number of outbreaks did not fall to the same degree, the average number of cases per outbreak and all-cause mortality decreased to a five-year low of 6% and 13.9%, respectively. Age and sex (Figure 11-1): Of the 166 reported cases, detailed client information was available for 142 cases (85.5%) associated with a CDI outbreak in a hospital. Of those, cases were predominantly 65 years or older (78.2%) and female (54.9%). Demographic data have been aggregated across all hospital outbreaks and likely reflect the age and gender profiles of the settings that have a higher risk of CDI outbreaks. Risk factors (Table 11-2): Risk factors were documented in 134 (80.7%) CDI cases associated with a CDI outbreak in a hospital. Although likely under-reported, antibiotic use continues to be the most common risk factor and was reported by 77.6% of cases. Seasonal trends (Figure 11-2): The seasonal pattern linked to CDI incidence is likely related to a number of factors, including the seasonality of respiratory illnesses such as influenza and the concurrent increase in antibiotic use. 8 Additional methodological issues On September 1, 2008, CDI outbreaks in public hospitals in Ontario and outbreak-associated cases became reportable in Ontario in accordance with the HPPA. CDI outbreaks in long-term care homes (LTCHs) are also reportable to the local Medical Officer of Health as institutional outbreaks of gastroenteritis. Based on information provided by hospitals and LTCHs, the data presented on CDI outbreaks and cases in this report were obtained from iphis and analyzed as follows: Outbreaks are allocated to onset year based on the onset date of the index case. Where onset date of the index case are missing, the created date is used. For outbreak-level analysis, where discrepancies are observed between reported CDI aggregate case counts and line-listed cases for the outbreak, the counts of cases and deaths are determined based on the higher number. For case-level analysis, only individual confirmed case records associated with confirmed CDI outbreaks in hospitals are included for demographic analysis. Cases with a nonreportable classification (e.g., probable cases) are excluded. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, August 2012 edition Geographic distribution (Map 11-1): The highest proportion of CDI outbreaks (20.0%) in 2013 was reported by Ottawa (n=6). The majority of public health units (63.8%) did not report a CDI outbreak in Public health units with academic teaching hospitals that serve a high proportion of at-risk patients are likely to have higher rates of CDI and may experience more outbreaks as a result. Reportable Disease Trends in Ontario,

43 Table Number of cases linked to CDI outbreaks and all-cause mortality: Ontario, Number of cases Year of CDI outbreak Number of outbreaks linked to a CDI outbreak Average number of cases per outbreak All-cause mortality % All-cause mortality Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2015/01/13]. Figure Number of CDI cases associated with a hospital outbreak by sex and age group: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2015/01/13]. Reportable Disease Trends in Ontario,

44 Table Risk factors for confirmed CDI cases associated with a hospital outbreak: Ontario, 2013 (n=134) Risk factor description Number of cases % Antibiotic use * Chronic illness/underlying medical condition (specify) Previous/recent hospitalization Antacid/Antiulcer medication or Proton pump inhibitors Immunocompromised status Prolonged hospitalization Abdominal/gastrointestinal surgery Feeding tube Previous C. difficile infection Close contact with a case Other GI conditions (specify) Other Unknown * Includes cases where antimicrobial therapy was selected as a risk factor. Antimicrobial therapy was inactivated as a risk factor in iphis in January Includes cases where chemotherapy was selected as a risk factor. Chemotherapy was inactivated as a risk factor in iphis January Figure Number of confirmed CDI outbreaks in 2013 and average number of CDI outbreaks from by month: Ontario Ontario Outbreaks: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2015/01/13]. Reportable Disease Trends in Ontario,

45 Map Number of CDI outbreaks by public health unit: Ontario, 2013 PHU Outbreaks Cases (n) PHU Outbreaks Cases (n) PHU Outbreaks Cases (n) ALG 0 0 KFL 0 0 REN 0 0 BRN 0 0 LAM 0 0 SMD 3 21 CHK 0 0 LGL 0 0 SUD 0 0 DUR 1 3 MSL 1 7 THB 1 4 ELG 0 0 NIA 2 13 TOR 3 16 EOH 0 0 NPS 0 0 TSK 0 0 GBO 0 0 NWR 0 0 WAT 0 0 HAL 0 0 OTT 6 45 WDG 1 7 HAM 4 9 OXF 0 0 WEC 0 0 HDN 0 0 PDH 0 0 YRK 1 6 HKP 3 21 PEE 3 12 HPE 0 0 PQP 0 0 HUR 0 0 PTC 1 2 Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2015/01/13]. Reportable Disease Trends in Ontario,

46 Chapter 12. Cryptosporidiosis General overview for 2013 Incidence and comparison to Canada (Figure 12-1): In 2013, there were 306 confirmed cases of cryptosporidiosis reported in Ontario, representing an incidence rate of 2.3 cases per 100,000 population. Since 2004, incidence rates in Ontario have been higher than the Canadian rates. Age and sex (Figure 12-2): The highest incidence rates were observed among the 0 4 year old age group (8.1 cases per 100,000 population), while the lowest incidence rates were observed among adults 50 years of age and over. Incidence rates by sex differ across various age groups, with no particular pattern. Seasonal trends (Figure 12-3): Cryptosporidiosis consistently shows a seasonal trend, with case counts increasing in the summer months, peaking in August. Geographic distribution (Map 12-1): The highest incidence rates were reported in Ontario s southwest region in Perth District (15.4 cases per 100,000 population), followed by Oxford County (12.6 cases per 100,000 population) and Grey Bruce (11.7 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 4.2 % (13/306) of cases and no deaths were reported. Figure Incidence of cryptosporidiosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

47 Figure Incidence of cryptosporidiosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Number of cryptosporidiosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month.. Reportable Disease Trends in Ontario,

48 Map Incidence of cryptosporidiosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

49 Chapter 13. Cyclosporiasis General overview for 2013 Incidence and comparison to Canada (Figure 13-1): In Ontario in 2013, there were 91 confirmed cases of cyclosporiasis, representing an incidence rate of 0.7 cases per 100,000 population. Between 2004 and 2013, rates in Ontario were higher than the national rates. The higher Ontario rates may be due to differences in laboratory testing and reporting requirements for cyclosporiasis cases in Ontario, compared to other jurisdictions in Canada. Age and sex (Figure 13-2): The highest incidence rates were observed among adults, particularly those in the year age groups. Incidence rates by sex were similar, with the exception of females years of age and 50 years of age and over, where rates were higher compared to males. Highlights Cyclopsora is not endemic to Ontario and it is very unlikely to be transmitted via person-to-person spread. As a result, it is expected that all reported cases in the province are either travel-related or associated with an imported food source, either as a non-travel sporadic or an outbreak case Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, June 2014 edition Seasonal trends (Figure 13-3): Cyclosporiasis tends to follow a seasonal pattern, with an increase during the spring and early summer months, from April to July. Geographic distribution (Map 13-1): The highest incidence rates were reported by Leeds Grenville and Lanark District (3.0 cases per 100,000 population) and Wellington-Dufferin-Guelph (2.9 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 1.1 % (1/91) of cases and no deaths were reported. Reportable Disease Trends in Ontario,

50 Figure Incidence of cyclosporiasis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note that New Brunswick and Prince Edward Island did not report on cyclosporiasis from 2009 to 2012; therefore, the population of these provinces were removed when calculating the national rate for the four years. Figure Incidence of cyclosporiasis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

51 Figure Number of cyclosporiasis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

52 Map Incidence of cyclosporiasis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario

53 Chapter 14. Cytomegalovirus Infection, Congenital General overview for 2013 Incidence (Table 14-1): In 2013, seven cases of congenital cytomegalovirus (CMV) infection were reported among newborns in Ontario, corresponding to an incidence rate of 5.0 cases per 100,000 live births. From 2004 to 2013, a total of 63 cases of congenital CMV infection were reported in Ontario, for an average of 6.3 cases per year over this period. The largest number of cases during this period was reported in 2011, with 11 cases reported. No comparable national data are available congenital CMV infections are not nationally notifiable. On December 4, 2013, this disease was removed from the Ontario Reportable Diseases List. Table Incidence of congenital cytomegalovirus infection: Ontario, Ontario rate Year Ontario cases per 100,000 live births Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/10]. Ontario Population: Live Births [ ], MOHLTC, IntelliHEALTH Ontario, extracted [2013/11/29]. Note: Live births data for 2012 and 2013 were unavailable at the time of data extraction; therefore, 2011 live births data were used to calculate rates for these years. Note: Congenital cytomegalovirus infection is not a nationally notifiable disease. Reportable Disease Trends in Ontario

54 Chapter 15. Diphtheria General overview for 2013 Under Ontario s publicly-funded immunization program, diphtheria toxoid-containing vaccine is routinely administered to infants in combination with vaccines against tetanus, pertussis, polio, and Haemophilus influenzae type b. 12,13 Children receive a dose of diphtheria toxoid-containing vaccine at two, four, six, and eighteen months of age, with additional booster doses at 4 6 years and years of age. 12 A booster dose is recommended every 10 years throughout life for continued protection. 12 Incidence and comparison to Canada: There were no cases of diphtheria reported in Ontario in Since 1995, no cases have been reported in the province. Annual Canadian incidence rates remained below 0.02 cases per 100,000 population for the period between 2004 and Reportable Disease Trends in Ontario,

55 Chapter 16. Giardiasis General overview for 2013 Incidence and comparison to Canada (Figure 16-1): In Ontario in 2013, there were 1,356 confirmed cases of giardiasis, representing an incidence rate of 10.0 cases per 100,000 population. The provincial incidence rate has been decreasing since 2004, and since 2010, the provincial rate has been lower than the national rate. Age and sex (Figure 16-2): The highest incidence rates were observed in the 0 4 year age group (18.7 cases per 100,000 population). Incidence rates were also higher among males compared to females, especially in young to middle-aged adults. Seasonal trends (Figure 16-3): A seasonal pattern has been observed for giardiasis in recent years, including 2013, with case counts peaking in the summer months. According to an Ontario study, cases reported during the winter months are largely attributed to international travel. 14 Geographic distribution (Map 16-1): The highest incidence rates were reported by Peterborough County- City (18.0 cases per 100,000 population), Niagara Region (17.7 cases per 100,000 population), and Toronto (14.3 cases per 100,000 population). Hospitalizations and deaths: 1.6 % (22/1,356) of cases reported hospitalization and no deaths were reported. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, April 2012 edition Reportable Disease Trends in Ontario,

56 Figure Incidence of giardiasis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure Incidence of giardiasis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

57 Figure Number of giardiasis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

58 Map Incidence of giardiasis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

59 Chapter 17. Gonorrhea General overview for 2013 Incidence and comparison to Canada (Figure 17-1): Gonorrhea is the second most frequently reported sexually transmitted infection in Ontario after chlamydia. Of the 4,536 cases of gonorrhea reported in 2013, 28.2% (1,278/4,536) were co-infected with chlamydia. From 2004 to 2013, the incidence rate of gonorrhea in Ontario gradually increased from a low of 26.5 cases per 100,000 population reported in 2005 to 33.5 cases per 100,000 population reported in Since 2005, rates of gonorrhea reported in Ontario have been lower than national rates. Age and sex (Figure 17-2): The incidence of gonorrhea in 2013 was greater among males, with an incidence rate of 42.8 cases per 100,000 population, compared to 24.4 cases per 100,000 population among females. Over 60% (2,847/4,536) of cases in 2013 were reported among males. The higher incidence of gonorrhea among males may be partly attributed to transmission among men who have sex with men (MSM). 15 Among male cases in 2013 reporting a risk factor, 45.0% reported MSM (data not shown). Similar to chlamydia, the highest incidence of gonorrhea was reported among year olds, in both males and females. The incidence of gonorrhea remained high in males up to 39 years of age before decreasing. Among females, the incidence was high among those years of age and then declined with increasing age. Laboratory data (Figure 17-3): The number of laboratory tests performed for gonorrhea has an impact on the number of cases identified because many gonorrhea cases are asymptomatic. Based on testing performed at Public Health Ontario Laboratories (PHOL), the percentage of tests that were positive for gonorrhea each month in 2013 ranged from 0.7% to 1.0%, with an overall per cent positivity of 0.8% for the year. Despite differences in tests performed month to month, stable per cent positivity may indicate continued transmission at similar levels. However, testing for gonorrhea is also completed at community laboratories throughout the province, which constitutes the majority of gonorrhea testing in Ontario. Geographic distribution (Map 17-1): The highest reported incidence rates of gonorrhea in 2013 occurred in Northwestern, Toronto, and Thunder Bay District public health units, with incidence rates of 81.4, 79.7 and 50.3 cases per 100,000 population, respectively. Highlights Several factors that may influence the reported incidence of gonorrhea include changes in screening and testing practices among clinicians, follow-up by public health units, and increasing resistance to antibiotics available to treat gonorrhea infections. 15 Evolving antibiotic resistance presents challenges to successful gonorrhea treatment, which in turn, impacts disease transmission. While a laboratory definition for what constitutes resistance to cefixime and ceftriaxone has not yet been agreed upon in North America, clinical failures associated with cefixime treatment have been reported in Ontario. 16 In response, Public Health Ontario released new provincial guidelines for testing and treatment of gonorrhea in April The extent of gonorrhea antimicrobial drug resistance in the province is likely underestimated, since it can only be detected using culture-based testing methods, rather than the nucleic acid amplification test that is most often used to diagnose gonorrhea in Ontario. Additional methodological issues Cases of gonorrhea are often undetected and, as a result, under-reported to public health units due to the occurrence of asymptomatic infections, particularly among women. Reportable Disease Trends in Ontario,

60 Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, November 2012 edition PHO s Monthly Infectious Diseases Surveillance Report, February 2015 edition PHO s Guidelines for testing and treatment of Gonorrhea in Ontario, 2013 Figure Incidence of gonorrhea: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

61 Figure Incidence of gonorrhea by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes seven cases of unknown age and/or sex. Figure Number and per cent of positive gonorrhea tests by month: Ontario, 2013 Source: Public Health Ontario Laboratories (PHOL), STI Online, extracted [2014/11/14]. Note: Data only include tests performed at PHOL. Reportable Disease Trends in Ontario,

62 Map Incidence of gonorrhea by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

63 Chapter 18. Group A Streptococcal Disease, Invasive (igas) General overview for 2013 Incidence and comparison to Canada (Figure 18-1): In 2013, 619 cases of invasive group A streptococcal (igas) disease were reported in Ontario, corresponding to an incidence rate of 4.6 cases per 100,000 population. From 2004 to 2013, there was an increase in the incidence rate of igas, from a low of 2.3 cases per 100,000 population in 2004 to over 4.0 cases per 100,000 population per year from 2010 onwards, with a high of 5.0 cases per 100,000 population in Overall, incidence rates of igas in Ontario have been similar to the Canadian incidence rates. Age and sex (Figure 18-2): In 2013, the overall incidence rate of igas was higher in males, with 4.9 cases per 100,000 population, compared to females, with 4.3 cases per 100,000 population. The incidence of igas was relatively high among infants less than one year of age, with an incidence rate of 7.8 cases per 100,000 population; it was lowest among those between 10 and 19 years of age; and highest in the 70 years and over age group for both males and females. The majority of igas cases (80.9%, 501/619) in 2013 were reported among those 30 years of age and older. Seasonal trends (Figure 18-3): The incidence of igas tends to follow a seasonal pattern, with higher case counts in the winter and early spring months. This seasonal trend was less apparent in 2013, however, where monthly case counts from January to August fluctuated between 43 and 60 cases. Case counts in 2013 reached a low in September and then peaked in December. Monthly case counts in 2013 exceeded the corresponding monthly five-year ( ) historical averages in six of 12 months. Laboratory data (Table 18-1): Laboratory testing for igas cases may include further differentiation by emm type, which assists in determining potential linkages among cases, identifying circulating strains associated with invasive disease, and identifying new strains that may be associated with more severe illness. 18 In 2013, an emm type was entered in iphis for 46.2% (286/619) of confirmed igas cases. Among igas cases for which an emm type was specified, emm 1 (22.7%, 65/286), emm 89 (8.0%, 23/286), and emm 28 (7.7%, 22/286) were the three most commonly reported emm types. This differs from the period between 2008 and 2012, where the top three emm types were emm 1, emm 89, and emm 3. There is geographic variation in the distribution of emm types across the province. For example, emm 1 is the most common emm type in Toronto (35.6%, 16/45) and the City of Ottawa (32.6%, 14/43), whereas the most common emm type in Waterloo Region is emm 3 (25.8%, 8/31), and in Northwestern, it is emm 11 (31.6%, 6/19). Among 24 health units with emm type data reported, the median number of emm types identified was 4.5 (range: 1 14). Geographic distribution (Map 18-1): In 2013, incidence rates of igas in Ontario were highest in Northwestern (30.8 cases per 100,000 population), Thunder Bay District (29.0 cases per 100,000 population), and Sudbury and District (11.5 cases per 100,000 population) public health units. However, 19.2% (119/619) of igas cases in 2013 were reported by Toronto. Hospitalizations and deaths: In 2013, 80.3% (497/619) of invasive igas cases were hospitalized and 11.8% (73/619) of cases were fatal. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, January 2013 edition Reportable Disease Trends in Ontario,

64 Figure Incidence of group A streptococcal disease, invasive (igas): Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Figure Incidence of group A streptococcal disease, invasive (igas) by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes one case where the client did not indicate male or female. Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

65 Figure Number of group A streptococcal disease, invasive (igas) cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Table Cases of group A streptococcal disease, invasive (igas) by emm type: Ontario, 2013 Cases emm Type n % emm emm emm emm emm emm emm emm All other (specified) Unspecified Total Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/18]. Note: Other is the sum of emm types with a frequency <2%. Unspecified refers to the sum of cases for which emm type was reported as unspecified or not reported at all. Reportable Disease Trends in Ontario,

66 Map Incidence of group A streptococcal disease, invasive (igas) by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario

67 Chapter 19. Group B Streptococcal Disease, Neonatal General overview for 2013 Incidence and comparison to Canada (Figure 19-1): In 2013, there were 59 cases of neonatal group B streptococcal (GBS) disease in Ontario, corresponding to an incidence rate of 42.2 cases per 100,000 live births. The incidence of neonatal GBS in Ontario ranged from 33 to 43 cases per 100,000 live births during the years , with incidence being lowest in 2007 and 2009 and highest in 2008 and Rates of neonatal GBS in Ontario were higher compared to the rest of Canada from A reduction in the difference between national and provincial rates occurred due to an increase in rates in the rest of Canada from Sex: The incidence rates of neonatal GBS among male and female neonates were similar in 2013, with 42.5 cases per 100,000 female live births, compared to 41.8 cases per 100,000 male live births. Among the 59 neonatal GBS cases reported in 2013, 49.2% (29/59) were female and 50.8% were male (30/59). Geographic distribution (Map 19-1): Cases of neonatal GBS were reported in 23 public health units in The highest incidence rates were reported from Renfrew County and District with cases per 100,000 live births, followed by Eastern Ontario and Northwestern, with and cases per 100,000 live births, respectively. Nearly one-quarter (14/59) of neonatal GBS cases were reported from Toronto in Deaths: There were five reported deaths among neonates related to this infection during Reportable Disease Trends in Ontario

68 Figure Incidence of group B streptococcal disease, neonatal: Ontario and Canada, Ontario Population: Live Births [2004 to 2011], MOHLTC, IntelliHEALTH Ontario, extracted [2013/11/29]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Canadian Rates: The denominators for rate calculations are live births from 2004 to Quebec did not report on neonatal GBS from ; Alberta did not report from ; Prince Edward Island did not report in Denominators (live births) have been adjusted in these years for the rate calculations. Note: Ontario rates: Live births data for 2012 and 2013 were unavailable at the time of data extraction; therefore, 2011 live births data were used to calculate rates for these years. Reportable Disease Trends in Ontario

69 Map Incidence of group B streptococcal disease, neonatal by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Live Births [2004 to 2011], MOHLTC, IntelliHEALTH Ontario, extracted [2013/11/29]. Reportable Disease Trends in Ontario

70 Chapter 20. Hantavirus Pulmonary Syndrome General overview for 2013 There were no cases of Hantavirus Pulmonary Syndrome reported in Ontario in A case of Hantavirus Pulmonary Syndrome has yet to be identified in Ontario since it became reportable in Reportable Disease Trends in Ontario

71 Chapter 21. Hemorrhagic Fevers General overview for 2013 Incidence and comparison to Canada: Viral hemorrhagic fevers (VHF) are not endemic to Canada, including Ontario. No cases of viral hemorrhagic fever have been reported in Ontario, or in Canada, since it was added back to the nationally notifiable disease list in Reportable Disease Trends in Ontario

72 Chapter 22. Hepatitis A General overview for 2013 Incidence and comparison to Canada (Figure 22-1): In Ontario in 2013, there were 100 confirmed cases of hepatitis A, representing an incidence rate of 0.7 cases per 100,000 population. Since 2004, rates in Ontario have been comparable to the Canadian rates. Age and sex (Figure 22-2): The highest incidence rates were observed in the 5 9 year age group (1.6 cases per 100,000 population) and the year age group (1.5 cases per 100,000 population). Rates were higher among males compared to females for most age groups among those 10 years of age and over. Seasonal trends (Figure 22-3): Historically, the incidence of hepatitis A has shown a seasonal pattern in Ontario, with a peak in late summer and early fall. 14 In 2013, however, this trend was not observed. Geographic distribution (Map 22-1): No public health unit jurisdiction had particularly high rates in Due to larger populations, the highest number of cases were reported by Toronto (31 cases) and Peel Region (23 cases). Hospitalizations and deaths: Hospitalization was reported for 27.0 % (27/100) of cases and no deaths were reported. Additional sources of information PHO s Provincial Infectious Diseases Advisory Committee released an updated guide, Hepatitis A Post Exposure Prophylaxis PHO s Monthly Infectious Diseases Surveillance Report, November 2014 edition Figure Incidence of hepatitis A: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario

73 Figure Incidence of hepatitis A by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Number of hepatitis A cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario

74 Map Incidence of hepatitis A by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario

75 Chapter 23. Hepatitis B General overview for 2013: Hepatitis B (acute) Incidence (Figure 23-1): In 2013, 109 cases of acute hepatitis B infections were reported in Ontario, representing an incidence rate of 0.8 cases per 100,000 population. From 2004 to 2013, the annual incidence rates of reported cases of acute hepatitis B generally decreased; a high of 1.4 cases per 100,000 population was reported in 2004, and the lowest rate was reported in 2012 at 0.7 cases per 100,000 population. National incidence rates of hepatitis B do not distinguish between acute, chronic, and unspecified cases, and are therefore not comparable to rates of acute hepatitis B in Ontario. Age and sex (Figure 23-2): The incidence rate of reported acute hepatitis B cases was higher among males than females in Males accounted for 56.9% (62/109) of all reported acute hepatitis B cases, corresponding to a reported incidence rate of 0.9 cases per 100,000 population, while females had a reported incidence rate of 0.7 cases per 100,000 population (data not shown). Overall, the incidence of reported hepatitis B was highest in the year age group, with 1.6 cases per 100,000 population. In both females and males, the reported incidence of hepatitis B was highest among those years of age at 1.4 and 1.7 cases per 100,000, respectively. Additional methodological issues Hepatitis B classification is based on various laboratory tests that measure serological responses and the presence of viral antigens in the blood over time; however, available test results may lead to unclear interpretation for purposes of case classification. Acute hepatitis B is often asymptomatic, and while some infections may resolve, others may progress to chronic infection; therefore, whether an individual is an acute case or chronic carrier may change over time. 19 This may result in one individual having two hepatitis B records, an acute case and a chronic case of hepatitis B, captured in iphis at different times. Consequently, counts of acute and chronic hepatitis B are not mutually exclusive in iphis and cannot be combined. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, October 2013 edition Geographic distribution (Map 23-1): In 2013, acute hepatitis B was reported in nearly three-quarters (72.2%, 26/36) of public health units in Ontario. The highest incidence rates were observed in Hastings & Prince Edward Counties, Wellington-Dufferin-Guelph, and Kingston, Frontenac and Lennox & Addington public health units, which had rates of 5.5, 5.4, and 5.0 cases per 100,000 population, respectively. Hospitalizations and deaths: In 2013, 10.1% (11/109 cases) of acute hepatitis B cases were hospitalized and two fatal cases were reported. Reportable Disease Trends in Ontario

76 Figure Incidence of hepatitis B (acute): Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Canadian rates are not shown as they include acute, chronic and unspecified hepatitis B cases and are therefore not directly comparable to Ontario s acute case counts and rates. Figure Incidence of hepatitis B (acute) by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario

77 Map Incidence of hepatitis B (acute) by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

78 General overview for 2013: Hepatitis B (chronic) Incidence: In 2013, 2,046 cases of chronic hepatitis B were reported in Ontario, representing an incidence rate of newly-reported chronic carriers of 15.1 cases per 100,000 population. This is lower than in 2012, when 2,295 cases were reported, representing an incidence rate of 17.1 cases per 100,000 population. As with acute hepatitis B, provincial rates of chronic hepatitis B are not directly comparable to national rates because of how national rates are calculated. Age and sex (Figure 23-3): The incidence of chronic hepatitis B in 2013 was higher among males than females, with sex-specific incidence rates of 17.3 and 13.0 cases per 100,000 population, respectively (data not shown). Overall, the age-specific incidence rates for reported chronic hepatitis B were highest among those between 25 and 39 years of age, with over two-fifths (40.4%, 827/2,046) of all the cases being reported in these groups. Among females, the incidence rate for reported chronic carriers was highest in the year age group, with 31.5 cases per 100,000 population; among males, the rate was highest in the year age group, with 35.6 cases per 100,000 population. Additional methodological issues A chronic carrier of hepatitis B is identified as an individual who has evidence of infection having been present for at least six months. While chronic carriers are most likely to have acquired their infection at birth or in early childhood, 20,21 the acute infection may not have been previously diagnosed or reported. The annual incidence of chronic hepatitis B consists of cases who are reported to public health units in Ontario during the year. This is likely to represent cases who were diagnosed with their chronic infection in the year and does not reflect when they acquired their acute infection or became a chronic carrier, which likely occurred considerably earlier. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, October 2013 edition Geographic distribution (Map 23-2): In 2013, 77.8% (28/36) of health units reported at least one case of chronic hepatitis B. The highest incidence rates of reported chronic hepatitis B were in the York Region and Toronto public health units, with rates of 35.5 and 34.3 cases per 100,000 population; the next highest rates by health unit were over 50% lower. Close to two-thirds (65.6%, 1,343/2,046) of chronic hepatitis B cases in 2013 were reported from these two public health units. Hospitalizations and deaths: In 2013, six cases of chronic hepatitis B cases were reported as being hospitalized and four cases were reported as fatal. Hospitalizations and deaths for chronic hepatitis B cases may occur long after cases are initially reported to, and followed up by, public health units and, as a result, they are likely to be under-reported in iphis. Reportable Disease Trends in Ontario,

79 Figure Incidence of hepatitis B (chronic) by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes two cases of unknown age and/or sex. Reportable Disease Trends in Ontario,

80 Map Incidence of hepatitis B (chronic) by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

81 Chapter 24. Hepatitis C General overview for 2013 According to the Ontario Burden of Infectious Disease Study (ONBOIDS), hepatitis C is the most burdensome infectious disease in Ontario based on measures of morbidity and mortality. 22 Incidence and comparison to Canada (Figure 24-1): In 2013, 4,156 hepatitis C infections were reported in Ontario, representing a reported incidence rate of 30.7 cases per 100,000 population. From 2004 to 2013, the reported incidence rate of hepatitis C in Ontario decreased over time; the highest rate was observed in 2004 and the lowest in 2013, at 42.2 and 30.7 cases per 100,000 population, respectively. There has been a similar decreasing trend in reported hepatitis C incidence in Canada; however, annual reported incidence rates in Ontario have been higher than the rest of Canada since Age and sex (Figure 24-2): Hepatitis C is more commonly reported among males. In 2013, males accounted for 62.6% (2,603/4,156) of hepatitis C cases reported in Ontario, with an overall incidence rate of 39.2 cases per 100,000 population, compared to an incidence of 22.5 cases per 100,000 population among females. Overall, the incidence of hepatitis C was highest among those and years of age. Among males, the incidence rate was highest in the year age group at 69.4 cases per 100,000 population; among females, the incidence rate was highest in the year age group at 43.9 cases per 100,000 population. Ten cases under the age of one were reported, likely reflecting mother-to-child transmission. Geographic distribution (Map 24-1): In terms of geographic distribution, the highest incidence rates in Ontario were reported by Thunder Bay, Kingston, Frontenac and Lennox & Addington, and Northwestern public health units, with 79.3, 77.1, and 70.3 cases per 100,000 population, respectively. Hospitalizations and deaths: In 2013, 1.1% (47/4,156 cases) of hepatitis C cases reported a hospitalization and 25 (0.6%) of the cases reported were fatal. Additional methodological issues Hepatitis C cases reported to public health units may include newly-acquired, chronic, and resolved infections. The presence of antibodies to the hepatitis C virus is required to meet the case definition for hepatitis C; 23 however, this laboratory test does not distinguish between newly-acquired, chronic, and resolved infections. As a result, reported hepatitis C rates may reflect cases that were infected in the past, but are newly diagnosed, rather than cases that have been newly acquired. RNA testing is required to identify resolved infections, but may not be routinely ordered after a positive antibody test result, and the results may not be reported to public health. Therefore, the number of reported hepatitis C cases based on antibody testing may overestimate the incidence of infectious hepatitis C; on the other hand, the incidence of reported hepatitis C cases can also underestimate true incidence because more than 90% of initial infections are asymptomatic and so can remain undiagnosed for a long period of time. 24 It should be noted that chronic sequalae, such as cirrhosis and liver cancer, are not likely to be accurately captured in iphis as they can take many years to develop and so may not be present and/or recognized at the time of hepatitis C reporting. The same is true for hospitalization and death due to hepatitis C; if either hospitalization or death takes place after health units have completed follow-up with the case, they may not be reported to the health unit and therefore not be recorded in iphis. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, December 2014 edition Reportable Disease Trends in Ontario,

82 Figure Incidence of hepatitis C: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

83 Figure Incidence of hepatitis C by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes five cases of unknown age and/or sex. Reportable Disease Trends in Ontario,

84 Map Incidence of hepatitis C by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

85 Chapter 25. Hepatitis D General overview for 2013 Incidence (Figure 25-1): Hepatitis D is a rare disease in Ontario. In 2013, two cases of hepatitis D were reported in the province, corresponding to an incidence rate of 0.1 cases per 1,000,000 population. From 2004 to 2013, a total of 36 cases of hepatitis D were reported in Ontario, on average 3.6 cases per year. The largest proportion of cases (22.2%, 8/36) during this period was reported in No comparable national data are available as hepatitis D is not nationally notifiable. Age and sex: Among all cases from 2004 to 2013, 66.7% (24/36) were males and 47.2% (17/36) were between 45 and 59 years of age. individuals would be classified as being co-infected with hepatitis B and D, but, in fact, they were super-infected (infected with hepatitis B first and then infected with hepatitis D). Additionally, individuals who may have been co-infected with hepatitis B and D may be underreported. Individuals who were tested and found to be positive for hepatitis B may not have been tested for hepatitis D until a later date, and therefore, are classified as super-infections when they should be classified as co-infections. On December 4, 2013, hepatitis D was removed from the Ontario Reportable Diseases List. Highlights All 36 hepatitis D cases reported in Ontario from 2004 to 2013 had evidence of an acute or chronic hepatitis B infection.the majority of reported cases of hepatitis D had a super-infection (91.7%, 33/36), whereby an individual chronically infected with hepatitis B was infected with hepatitis D. Only three (8.3%) of the reported hepatitis D cases were co-infections, whereby the individual acquired acute hepatitis B and hepatitis D concurrently. There are limitations to classifying individuals as having either a hepatitis D super-infection or co-infection. Data from iphis were used to classify hepatitis D cases as being either super-infections or coinfections. These data are limited as they are based on when an individual was diagnosed with hepatitis B and D, rather than when an individual acquired hepatitis B and D. It is possible the number of hepatitis D super-infections is under-reported. Individuals may have been infected with hepatitis B, undiagnosed, and then acquired hepatitis D, and following their infection with hepatitis D, had testing completed. With positive results for both hepatitis B and D obtained at the same time, these Reportable Disease Trends in Ontario,

86 Figure Incidence of hepatitis D: Ontario, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/09]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Hepatitis D is not a nationally notifiable disease. Reportable Disease Trends in Ontario,

87 Chapter 26. Herpes, Neonatal General overview for 2013 Incidence (Table 26-1): In 2013, two cases of neonatal herpes were reported in Ontario, corresponding to an incidence rate of 1.4 cases per 100,000 live births. From 2004 to 2013, a total of 63 cases of neonatal herpes were reported, on average, 6.3 cases per year over this period. The largest number of cases during this period was reported in No comparable national data are available as neonatal herpes is not nationally notifiable. On December 4, 2013, this disease was removed from the Ontario Reportable Diseases List. Table Incidence of herpes, neonatal: Ontario, Ontario rate per Year Ontario cases 100,000 live births Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/10]. Ontario Population: Live Births [ ], MOHLTC, IntelliHEALTH Ontario, extracted [2013/11/29]. Note: Live births data for 2012 and 2013 were unavailable at the time of data extraction; therefore, 2011 live births data were used to calculate rates for these years. Note: Neonatal herpes is not a nationally notifiable disease. Reportable Disease Trends in Ontario,

88 Chapter 27. Influenza General overview for the influenza season Incidence (Figure 27-1): During the influenza season, which ran from September 1, 2012 to August 31, 2013, 9,781 cases of laboratory-confirmed influenza were reported in Ontario, corresponding to an incidence rate of 72.2 cases per 100,000 population. The incidence of influenza fluctuates from season to season due to a variety of factors, including characteristics of the circulating strains and susceptibility of the population. It should be noted that reported cases represent just a fraction of those infected with influenza. Over the past 10 influenza seasons, the highest reported incidence rate was observed for the season. Other seasons with high incidence included the and seasons, which can primarily be attributed to the influenza A (H1N1) pdm09 pandemic that circulated in the spring and fall of Age and sex (Figure 27-2): Incidence rates of laboratoryconfirmed influenza cases were higher for females than males, at 77.2 and 66.6 cases per 100,000 population, respectively (data not shown). Age-specific differences between males and females were also observed, for example, the incidence rate in children less than one year of age was higher in males than females. The highest age-specific incidence rates of laboratoryconfirmed influenza were observed among children under the age of one and adults 65 years of age and older. Higher rates of reported disease in these age groups may reflect health care-seeking behaviour and/or testing practices in general; for those 65 years of age and over, testing may done as part of institutional outbreaks. Also, these age groups may present with more severe disease, requiring hospitalization and/or intensive care, resulting in a higher likelihood of being tested and confirmed as a case of influenza. Geographic distribution (Map 27-1): Among public health units, the incidence of laboratory-confirmed influenza for the season was highest in North Bay-Parry Sound District, Kingston, Frontenac and Lennox & Addington, and Peterborough County-City, with rates of 222.6, 138.7, and cases per 100,000 population, respectively. Although these rates may reflect true geographical differences in influenza activity, they may also result from differences in testing practices by clinicians or health-seeking behaviours. Seasonal trends (Figure 27-3): While influenza cases are reported throughout the year in Ontario, influenza activity is seasonal and peaks during the colder months. The incidence of influenza was highest in December and January of the season, and 74.5% (7,286/9,781) of all cases were reported in those months, as has been previously observed for the influenza A/H3N2 subtype, which was the dominant circulating subtype in Ontario. Compared to previous non-pandemic influenza seasons, the season started earlier and had fewer cases than expected in March, 25 which over the past five seasons, had the highest number of cases reported on average. The reason that March had the highest number of cases on average is that influenza B activity usually peaks around March, and influenza A is still circulating at moderate levels. Laboratory data (Table 27-1): Based on data reported through iphis, influenza A was the dominant circulating influenza type during the season, and accounted for 89.4% (8,741/9,781) of laboratoryconfirmed influenza cases in Ontario. Subtype information was available for 3,671 cases of laboratoryconfirmed influenza A. H3N2 was the dominant subtype, representing 90.8% (3,334/3,671) of cases (data not shown). 25 The percentage of specimens submitted to the Public Health Ontario Laboratories (PHOL) that was positive for influenza A (i.e., per cent positivity) peaked in week 52 at 40.5%, while influenza B per cent positivity was at its highest levels between weeks 15 and 18 and peaked in week 15 at 8.3% (Figure 27-4). Reportable Disease Trends in Ontario,

89 Hospitalizations and deaths: During the season, 37.8% (3,699/9,781 cases) of laboratoryconfirmed influenza cases were hospitalized and 2.6% (254/9,781) of cases were fatal. Highlights The season had the highest number of laboratory-confirmed cases of influenza reported over the past 10 seasons, even compared to the two seasons which included the influenza A (H1N1) pdm09 pandemic. The peak per cent positivity for influenza A, the dominant influenza type in , was 40%, and per cent positivity remained above 30% for four consecutive weeks. This was higher than the season when influenza A H3N2 was also the dominant subtype; in the season, per cent positivity peaked at 34% and only exceeded 30% for one week. 26 Over the past five seasons, the season had the highest number of influenza outbreaks in institutions (e.g., hospitals, LTCHs, and retirement homes). 25,27,28 Influenza was the causative organism for 646 outbreaks (45%) among a total of 1,437 reported respiratory infection outbreaks in Ontario. 25 During the and seasons, influenza was the causative agent for 19% (140/734) and 42% (437/1,040) of reported respiratory infection outbreaks, respectively. 27,28 Of all the institutional influenza outbreaks reported in , 55.6% (359/646) were in LTCHs, 20.4% (132/646) were in retirement homes, and 8.7% (56/646) occurred in hospitals. Additional methodological issues Reporting of laboratory-confirmed influenza cases to local public health units significantly underestimates the burden of influenza in Ontario, since many individuals with influenza-like illness never seek care or have confirmatory laboratory testing performed. Patients who are hospitalized are more likely to be tested for influenza, and are tested using polymerase chain reaction tests that are more sensitive than the culturebased tests used for community dwelling cases. Due to the large volume of confirmed cases of influenza that are reported in some public health units each season, as well as challenges with case follow-up, it can be difficult to obtain information on hospitalizations and deaths for some laboratory-confirmed cases, resulting in under-reporting of these parameters in iphis, and hence, underestimation of the severity of influenza. Additional sources of information Ontario Influenza and Respiratory Infection Surveillance Smmary Report: Season Ontario Respiratory Virus Bulletin website For the influenza season, there was reduced influenza vaccine effectiveness for the H3N2 subtype. This is believed to be related to mutations in the eggadapted H3N2 vaccine strain,which resulted in it being different than the circulating strain. For further information, please see study results for the effectiveness of the influenza vaccine. 29 The percentage of reported cases that were reported as hospitalized in (37.8%) was slightly lower compared to the (38.7%; 2,342/6,049) H3N2 dominant season, 27 but higher than in the (31.0%; 1,223/3,940) influenza B dominant season. 28 Reportable Disease Trends in Ontario,

90 Figure Incidence of laboratory-confirmed influenza: Ontario, to seasons Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/05/14]; seasons 2003/04, 2008/09, and 2009/10 extracted [2013/11/13]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: National rates for influenza are not available at this time. Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Figure Incidence of laboratory-confirmed influenza by age and sex: Ontario, season Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes 33 cases of unknown age and/or sex. Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

91 Figure Number of laboratory-confirmed influenza cases by month: Ontario, season Note: Monthly five year averages were calculated using the most recent five non-pandemic influenza seasons ( to , with the and seasons excluded). Table Laboratory-confirmed influenza cases by type: Ontario, season Cases Influenza Type n % Influenza A 8, Influenza B 1, Influenza A and B Total 9, Reportable Disease Trends in Ontario,

92 Figure Number of influenza tests and per cent of positive tests by specimen collection week: Ontario, season Source: Public Health Ontario Laboratories (PHOL), Laboratory Information Management System, extracted [2014/03/26]. Note: Includes specimens tested for influenza at PHOL by all testing methods. The PHOL performs the majority of testing for influenza and other respiratory viruses; however, other microbiology laboratories also perform these tests. The week is assigned based on the week of specimen collection. Weeks were assigned based on the date the specimen was received at the laboratory if specimen collection date was unavailable. Reportable Disease Trends in Ontario,

93 Map Incidence of laboratory-confirmed influenza by public health unit of residence: Ontario, season PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

94 Chapter 28. Invasive Haemophilus influenzae, type b General overview for 2013 Haemophilus influenzae is a bacterium that can be differentiated into six serotypes (a to f) that can cause invasive disease, or non-typeable strains. While all invasive H. influenzae diseases are reportable at the national level, only confirmed and probable cases of invasive H. influenzae type b (Hib) are reportable in Ontario. Following the introduction of the infant Hib vaccination programs, there has been a decline in disease incidence in all age groups, including those not targeted by vaccination, in Ontario and the rest of Canada. 30,31 Incidence and comparison to Canada (Figure 28-1): In 2013, six confirmed cases of Hib were reported in Ontario, representing an incidence of 0.4 cases per 1,000,000 population. The annual incidence rate of invasive Hib disease in Ontario ranged between 0.1 and 0.9 cases per 1,000,000 population between 2000 and 2013, and was lower than the Canadian rate in all years between 2000 and Age and sex (Figure 28-2): The highest incidence occurred in infants less than one year of age, however, this was based on a single case. The median age of cases in 2013 was 50.2 years, ranging between seven months and 79.2 years; five of the six cases were among adults. Of the six cases reported in 2013, five were male. Immunization: Immunization status could be determined for three of the six cases; however, only one of the three was eligible to receive the publicly-funded routine infant Hib vaccines. This case occurred in an infant under one year of age who was only partially immunized, and therefore, was not vaccine-preventable. Immunization details are essential to fully assess the immunization status of all reported cases, and may make it possible to determine if cases were attributable to failure to vaccinate or the result of vaccine failure. In Ontario, a polysaccharide Hib vaccine was introduced in 1987, followed by a more effective conjugate vaccine in As of September 1992, a four-dose schedule of Hib-containing vaccine was implemented and recommended to be administered as a primary series at two, four, and six months of age, with a booster dose given at 18 months of age. 13 Hib vaccine is administered to infants in combination with vaccines against diphtheria, tetanus, pertussis, and polio. Hospitalizations and deaths: Four of the six cases were reported as hospitalized in No deaths were reported among the confirmed cases. Geographic distribution: The public health unit-specific incidence rates ranged from 0.0 to 12.3 cases per 1,000,000 population in 2013; 31 public health units did not have a case in Between 2000 and 2013, higher rates were observed in northern public health units. Additional methodological issues Data for this analysis were obtained by linking and validating cases that were reported in iphis with laboratory data received from the Public Health Ontario Laboratories (PHOL). Both iphis and PHOL data for 2013 cases were extracted in 2014, and were linked for the first time for this analysis. Cases for were obtained from a previously linked dataset. The purpose of the data linkage was to identify additional confirmed cases that were not reported in iphis, and to help exclude cases that were incorrectly classified as Hib. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, November 2013 edition Reportable Disease Trends in Ontario,

95 Figure Incidence of Haemophilus influenzae, type b: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL). Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Nunavut did not report on Hib in New Brunswick did not report on Hib in The populations of these provinces have been removed for rate calculations. Figure Incidence of Haemophilus influenzae, type b by age: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL). Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

96 Chapter 29. Lassa Fever General overview for 2013 Incidence and comparison to Canada: Lassa fever is not endemic to Ontario. As of 2013, no cases of Lassa fever have ever been reported in Ontario. The disease is not nationally notifiable and therefore no Canadian data are available. Reportable Disease Trends in Ontario,

97 Chapter 30. Legionellosis General overview for 2013 Incidence and comparison to Canada (Figure 30-1): In 2013, 264 cases of legionellosis were reported in Ontario, an incidence rate of 2.0 cases per 100,000 population. From 2004 to 2013, the incidence of legionellosis increased from 0.1 cases per 100,000 population in 2004 to 2.0 cases per 100,000 population in The annual incidence rates of legionellosis in Ontario from 2004 to 2013 were higher than the rest of Canada, except in 2004 and 2012 when the provincial and national rates were essentially the same. Age and sex (Figure 30-2): In 2013, males accounted for 67.0% (177/264) of all cases reported in Ontario. The incidence rate among males was 2.7 cases per 100,000 population, which was double the rate among females of 1.3 cases per 100,000 population. The incidence of legionellosis increased with increasing age for both sexes. One case of legionellosis was reported among individuals less than 20 years of age in 2013, and 81.8% (216/264) of cases were reported among individuals 50 years of age and older. The highest incidence rates were reported among men 70 years of age and older, with 8.1 cases per 100,000 population. Seasonal trends (Figure 30-3): The incidence of legionellosis follows a seasonal pattern, with the majority of cases occurring in summer and fall. The majority of cases in 2013 were reported from June to September (65.5%, 173/264), with the highest number of cases observed in July, with 25.4% (67/264) of the cases. The number of cases reported each month in 2013 exceeded the corresponding monthly five-year ( ) average case count in every month except December. Laboratory data (Figure 30-4): The number of specimens received and tested for Legionella at the Public Health Ontario Laboratories (PHOL) fluctuated by month, and the highest per cent positivity (i.e., percentage of tests that were positive for Legionella) occurred in July (7.4%, 59/801). Geographic distribution (Map 30-1): The incidence rates of legionellosis were highest in Timiskaming, Niagara Region, and Peel Region public health units, with rates of 5.8, 5.4 and 3.7 cases per 100,000 population, respectively. In 2013, over half of the cases (54.5%, 144/264) in Ontario were reported from four public health units in the Greater Toronto Area: Toronto, Peel Region, Durham Region, and Halton Region. Six public health units did not report any cases of legionellosis in Hospitalizations and deaths: In 2013, 84.1% (222/264) of legionellosis cases were hospitalized, with deaths reported in 9.5% (25/264) of cases. Highlights Over the 10 years from 2004 to 2013, the case counts and incidence rates of legionellosis were highest in While the overall demographic distribution of legionellosis was consistent with previous years, with older males being at greatest risk for infection, the expected seasonal increase occurred earlier than usual in 2013 (Figure 30-1). 32 As a result, on June 28, 2013, PHO issued an Enhanced Surveillance Directive (ESD) to local public health units. On July 24, 2013, PHO updated the ongoing ESD to request that public health units submit a Case Report Form (CRF) to collect more detailed exposure type and location information for each case of legionellosis. Despite collecting extensive data on potential exposures in both iphis and the supplemental CRF, a common exposure was only identified for two cases in a northern health unit. 32 The overall per cent positivity and the total number of tests were higher in 2013 (3.1 per cent positivity; 8,530 tests), compared to 2012 (2.5 per cent positivity; 6,984 tests). In 2013, the highest per cent positivity occurred Reportable Disease Trends in Ontario,

98 in July at 7.4%; compared to 2012 when the highest per cent positivity occurred in August at 10%. The per cent positivity in June 2013 indicated an earlier start to the season than is normally observed, and activity remained elevated for a longer period of time compared to For more information, please see the full report on Epidemiology of legionellosis in Ontario, Additional sources of information PHO s Epidemiology of Legionellosis in Ontario, 2013 PHO s Monthly Infectious Diseases Surveillance Report, December 2011 edition PHO s Monthly Infectious Diseases Surveillance Report, May 2014 edition Figure Incidence of legionellosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

99 Figure Incidence of legionellosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Figure Number of legionellosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

100 Figure Number of patients tested and per cent positivity for Legionella by test month: Ontario, 2013 Source: Public Health Ontario Laboratories (PHOL), Laboratory Information Management System, extracted [2014/08/26]. Note: Includes all patients tested for Legionella by all methods (i.e., urine antigen, culture, polymerase chain reaction, and direct fluorescent antibody); each patient is only counted once regardless of number of specimens tested. Per cent positivity is the percentage of patients tested with at least one positive result. Test month is based on the month the specimen was received at the lab. Reportable Disease Trends in Ontario,

101 Map Incidence of legionellosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

102 Chapter 31. Leprosy General overview for 2013 Incidence and comparison to Canada (Table 31-1): Leprosy is a rare disease in Ontario. In 2013, one confirmed case of leprosy was reported in the province, corresponding to an incidence rate of 0.1 cases per 1,000,000 population. From 2004 to 2013, a total of 30 cases of leprosy were reported in Ontario, resulting in an average of 3.0 cases per year over this period. The largest number of cases during this period was reported in 2008 and 2009, with five confirmed cases each year. Over this period, provincial incidence rates of leprosy were consistently higher or similar to the Canadian rates. None of the cases reported from 2004 to 2013 were indicated to have acquired their infection in Ontario. Age and sex: Among all cases reported from 2004 to 2013, 80.0% (24/30) were male, and 63.3% (19/30) of all cases were over the age of 40. Table Incidence of leprosy: Ontario and Canada, Year Ontario cases Ontario rate (per 1,000,000 population) Canadian rate (per 1,000,000 population) Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

103 Chapter 32. Listeriosis General overview for 2013 Incidence and comparison to Canada (Figure 32-1): In Ontario in 2013, there were 44 confirmed cases of listeriosis, representing an incidence rate of 0.3 cases per 100,000 population. Since 2007, rates in Ontario have been comparable to the Canadian rates. Age and sex (Figure 32-2): The highest incidence rates were observed in the 70 years and over age group (1.5 cases per 100,000 population), followed by the year age group (0.8 cases per 100,000 population). There was little difference in the incidence rates by sex, likely due to small case counts. Outbreak activity In September 2013, a National Outbreak Investigation Coordination Committee was established to investigate a cluster of listeriosis cases with a matching pulse-field gel electrophoresis pattern. Two cases in Ontario, with onset dates in July and August, were linked to the outbreak. A source was not identified. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, February 2014 edition Seasonal trends (Figure 32-3): Listeriosis tends to follow a seasonal pattern, with increased incidence in the warmer months, particularly in July and August. The large peak observed in the 5-year average over the summer months is due in part to a large national outbreak that occurred in Geographic distribution (Map 32-1): Due to the larger population, the highest number of cases was reported by Toronto (7 cases), however, the rate was mid-range. Hospitalizations and deaths: Hospitalization was reported for 77.4 % (34/44) of cases and death was reported for 9.1 % (4/44) of cases. However, a report from the Public Health Agency of Canada s National Enhanced Listeriosis Surveillance Program reported a fatal outcome for 17% 20% of cases in Ontario from 2011 to The difference between the case fatalities reported in iphis and those captured through the national surveillance program is likely due to more complete reporting of case information in the enhanced surveillance program. Furthermore, death outcomes reported in iphis are only captured at the time of the case investigation. Reportable Disease Trends in Ontario,

104 Figure Incidence of listeriosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; listeriosis became nationally notifiable in 2007 and national data were available up to Note that Northwest Territories did not report on listeriosis from 2009 to 2011; therefore, the population of the territory was removed for the rate calculation of the three years. Figure Incidence of listeriosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

105 Figure Number of listeriosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

106 Map Incidence of listeriosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

107 Chapter 33. Lyme Disease General overview for 2013 Incidence and comparison to Canada (Figure 33-1): In Ontario in 2013, there were 184 confirmed and 145 probable cases of Lyme disease, representing a combined incidence rate of 2.4 cases per 100,000 population. Since 2004, the Ontario incidence rate for Lyme disease has been increasing. The observed increase in provincial incidence rates may be due to a number of factors, including increasing numbers of individuals exposed to Lyme disease in new and expanding risk areas, as well as increased public and physician awareness of the disease, leading to increased diagnosis and reporting. 34 Lyme disease has been nationally notifiable since 2009 and since then, incidence rates in Ontario have been above the Canadian rates. Age and sex (Figure 33-2): Although Lyme disease can be contracted at any age, the highest incidence rates were observed in older adults in the and year age groups. Rates were higher among males compared to females, with the exception of the 5 9 year age group. Individuals who spend significant amounts of time outdoors, such as campers, hikers, and hunters are at greatest risk for Lyme disease due to the increased likelihood of exposure to infected ticks, especially in Lyme disease risk areas. Seasonal trends (Figure 33-3): Lyme disease tends to follow a seasonal pattern, with an increased number of cases reported in the summer months, which corresponds with the nymphal stage of the blacklegged tick s life cycle. Due to their small size, an infected nymph is less likely to be noticed when attached, and is thus more likely to feed for more than 24 hours with resultant transmission of the Lyme disease bacterium. Geographic distribution (Map 33-1): The highest incidence rates were reported in the Leeds, Grenville and Lanark District (26.6 cases per 100,000 population), followed by Kingston, Frontenac and Lennox & Addington (26.5 cases per 100,000 population), and Eastern Ontario (15.1 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 5.5 % (18/329) of cases and no deaths were reported. Additional methodological issues Prior to 2009, probable cases of Lyme disease were not reportable. In early 2009, the provincial case definition for Lyme disease was revised to include both confirmed and probable cases such that certain cases that previously met the confirmed case definition were required to be reported as probable. The impact of this change was substantial and probable cases after 2009 constituted a significant proportion of total case counts. As a result, probable case counts are included in total counts to ensure valid comparisons over time. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, September 2013 PHO's Vector-borne Diseases 2013 Summary Report PHO's Lyme Disease Testing Labstract Reportable Disease Trends in Ontario,

108 Figure Incidence of confirmed and probable Lyme disease: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; Lyme disease became nationally notifiable in 2009 and national data were available up to Figure Incidence of confirmed and probable Lyme disease by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

109 Figure Number of confirmed and probable Lyme disease cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

110 Map Incidence of confirmed and probable Lyme disease by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

111 Chapter 34. Malaria General overview for 2013 Incidence and comparison to Canada (Figure 34-1): In 2013, there were 210 confirmed cases of malaria, representing an incidence rate of 1.6 cases per 100,000 population. Of the 210 confirmed cases, the majority were due to Plasmodium falciparum (201 cases, 60.0%). The incidence rate increased in 2010, but has since declined. Since 2004, incidence rates in Ontario have been higher than the Canadian rates. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, April 2014 edition Nelder MP, Russell C, Williams D, Johnson K, Li L, Baker SL, et al. Spatiotemporal dynamics and demographic profiles of imported plasmodium falciparum and plasmodium vivax infections in Ontario, Canada ( ). PLoS One. 2013;8(9):e76208 Age and sex (Figure 34-2): The highest incidence rates were observed in the and year age groups. Rates were higher in males, compared to females. Seasonal trends (Figure 34-3): The majority of cases were reported from May to September. Parasite species (Table 34-1): P. falciparum (60.0%), followed by P. vivax (28.1%) were the most frequently reported parasite species. Geographic distribution (Map 34-1): The highest incidence rates were reported by Hamilton (3.3 cases per 100,000 population), Toronto (2.9 cases per 100,000 population), and Peel Region (2.6 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 41.4 % (87/210) of cases and no deaths were reported. Reportable Disease Trends in Ontario,

112 Figure Incidence of malaria: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure Incidence of malaria by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

113 Figure Number of malaria cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Table Malaria cases by Plasmodium species: Ontario, 2013 Cases Plasmodium Species n % P. falciparum P. vivax P. ovale P. malariae Unspecified species Total Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/15]. Reportable Disease Trends in Ontario,

114 Map Incidence of malaria by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

115 Chapter 35. Measles General overview for 2013 Indigenous measles has been eliminated from Canada; the last endemic case of measles was reported in Under the guidance of the Pan American Health Organization, countries of the Americas are currently documenting the elimination of measles. 36 As the disease remains endemic in other parts of the world, importation of cases continues to occur. Immunization with two doses of a measles-containing vaccine is the most effective method of preventing disease. In Canada, measles vaccine is only available in combination with mumps, rubella, and varicella vaccines (MMR and MMRV vaccines). A two-dose measles immunization program was implemented in Ontario in Presently, the first MMR dose is administered at 12 months of age, while the second dose is administered as a combined MMRV vaccine between four and six years of age. Incidence and comparison to Canada (Figure 35-1): In 2013, 15 confirmed cases of measles were reported in Ontario, representing an incidence of 1.1 cases per 1,000,000 population. The annual incidence rate of measles ranged from 0.0 to 4.5 cases per 1,000,000 population between 2004 and In Canada, low incidence rates have been observed over the past decade except in 2007 and 2011, which were related to outbreaks in Quebec. Age and sex (Figure 35-2): The highest incidence rates of measles were observed among the 1 4 year age group (12.2 cases per 1,000,000 population) and infants under one year (7.0 cases per 1,000,000 population), although rates are unstable due to low case counts. Twelve (80.0%) of the 15 confirmed cases in 2013 were males. Of these, six (50.0%) were in the 1 4 year age group. Importation status: Importation status was available for three (20.0%) of the 15 measles cases in 2013, all of whom were imported. While the remaining twelve cases had unknown status, they were assumed to be non-endemic cases, since epidemiological and molecular measles surveillance confirmed the absence of circulation of any one dominant viral strain (further information below). 37 Genotype (Table 35-1): Genotype information was ascertained for all 15 confirmed cases in The most common genotypes were D8 (46.7%) and B3 (40.0%). Immunization: Of the 15 confirmed cases of measles in 2013, immunization status was available for 12 cases (80.0%). Of these, three cases (two children less than five years and one individual 19 years of age) had received a single dose of measles-containing vaccine and nine were unimmunized, including one infant under one year of age. Geographic distribution (Map 35-1): In 2013, cases of measles were reported by four public health units. Among the four, Halton Region had 6 cases and reported the highest incidence rate with 11.1 cases per 1,000,000 population. Hospitalizations and deaths: Only one of the 15 cases of measles in 2013 was reported as hospitalized and none of the cases had a fatal outcome reported. Highlights In 2013, two separate clusters of measles were reported in Ontario. The first cluster of five cases occurred in a childcare centre in Toronto between February and March The source of exposure for the index case was unknown. All cases were between the ages of one and four years, and four of the five cases were unimmunized. These cases were confirmed to have genotype B3. The second cluster of cases involved six cases of measles in Halton Region, occurring between June and July The outbreak, which started with three unimmunized cases who travelled in British Columbia during the exposure period, including time Reportable Disease Trends in Ontario,

116 spent in two international Canadian airports, resulted in four generations of cases. Laboratory findings indicate that all cases in this cluster were genotype D8. 37 Over the years, assessment and documentation of immunization and travel histories are being improved as part of the effort to maintain Canada s elimination status. 38 Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, August 2013 edition Additional methodological issues In determining the importation status of the 15 confirmed cases of measles in 2013, consultations within the program area,as well as review of iphis data fields (i.e., exposures, comments, case notes, and risk factor notes), were undertaken. Furthermore, importation status for the cases reported between 2006 and 2012 were derived from previously published literature. 38 Figure Incidence of measles: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canada Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

117 Figure Incidence of measles by age: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Table Genotype distribution of measles cases: Ontario, 2013 Genotype Cases n % D B D H Total Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL), extracted [2013/12/13]. Reportable Disease Trends in Ontario,

118 Map Incidence of measles by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

119 Chapter 36. Meningococcal Disease, Invasive General overview for 2013 Invasive meningococcal disease (IMD) is an endemic but rare disease in Ontario. A single-dose conjugated meningococcal vaccine against serogroup C (MCC) has been publicly funded in Ontario for one-year olds since September This was followed by a school-based single-dose MCC vaccine program for Grade 7 students in January 2005, which was replaced with a quadrivalent meningococcal conjugated vaccine (MCV4) against serogroups A, C, Y, and W-135 in As of December 2013, a new meningococcal B vaccine (Bexsero ) has been approved in Canada but is not publicly funded in Ontario. 39 Incidence and comparison to Canada (Figure 36-1): Between 2000 and 2013, there were 815 IMD cases in Ontario, with 23 confirmed cases occurring in Overall incidence ranged from 0.9 cases per 100,000 in 2001 to 0.2 cases per 100,000 in National incidence over the same time period showed a similar decrease in IMD rates. Serogroups (Figure 36-2): IMD epidemiology varies by serogroup. In recent years, serogroup B has been the most common form of IMD in Ontario. The incidence of serogroup B disease has varied throughout , with the lowest incidence of 0.07 cases per 100,000 occurring in Incidence of serogroup C disease has decreased over time between 2000 and 2013, suggesting vaccine program impact. Between 2009 and 2013, serogroup W-135 disease incidence remained low, (<0.03 cases per 100,000) and serogroup Y incidence decreased. Age and sex (Figure 36-3) : The median age of IMD cases that occurred in 2013 was 45.8 years, with a range of 2 weeks to 92.4 years; 26.1% of cases were in children younger than 18 years. The highest age-specific incidence was observed in infants less than one year (n=2), followed by children 1 4 years. Overall, 13 (56.5%) of the cases were female. Seasonality: In 2013, as in previous years, a seasonal pattern was observed where the occurrence of IMD peaked in winter months (26.1% of cases occurring in 2013). The average number of IMD cases is consistently higher in winter months compared to summer months, from 2000 to Some evidence from the literature suggests that the increase in IMD in winter/spring is associated with the influenza virus enhancing the risk of bacterial infection in colonized individuals. 40 Immunization: Immunization status could be assessed for 17 of the 23 (73.9%) IMD cases reported in 2013, and all of them were reported as unimmunized. Efforts to improve documentation are currently underway. Geographic distribution (Map 36-1): In 2013, some geographic variation was observed, although only 12 of the 36 public health units reported cases of IMD. Public health units with the highest incidence were Kingston, Frontenac and Lennox & Addington (1.5 cases per 100,000 population); Grey Bruce (1.2 cases per 100,000 population); and Chatham-Kent (0.9 cases per 100,000 population); however, case counts are small and rates are unstable. Hospitalizations and deaths: Among the 23 IMD cases reported in 2013, 73.9% (n=17) of cases reported hospitalization and 21.7% (n=5) died. Highlights Documentation of immunization status is a critical data element for IMD surveillance. As noted above, immunization status was documented for 73.9% of cases in This is an increase from the 8.8% of cases in 2012 where immunization status was completed, and is a result of validating the immunization status of each case within the program area. Complete entry of immunization histories remains an important Reportable Disease Trends in Ontario,

120 component of provincial reporting in Ontario and essential for assessing the impact of vaccine programs. Additional methodological issues Unique IMD cases were identified using two data sources, iphis and the Public Health Ontario Laboratories (PHOL). Confirmed and probable cases (starting in 2009) from iphis were linked to PHOL records using probabilistic record linkage from 2000 and 2010 and deterministic record linkage from 2011 to PHOL records not matched to iphis were also included as distinct cases. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, July 2014 edition For the analysis conducted to assess seasonality, winter months were defined as January to March, and summer months were from July to September. Figure Incidence of invasive meningococcal disease: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL), extracted [2014/04/25]; confirmed ( ) and probable ( ) cases were included. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

121 Rate per 100,000 population Figure Incidence of invasive meningococcal disease by serogroup*: Ontario, /2005: MCC Age 1 & Grade : MC4 Grade Serogroup B Serogroup C Serogroup W-135 Serogroup Y Year Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL); confirmed ( ) and probable ( ) cases were included Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. *Note: Excludes 106 cases with A, Z, non-groupable and unknown serogroups. Figure Incidence of invasive meningococcal disease by age: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16] and Public Health Ontario Laboratories (PHOL); both confirmed and probable cases were included. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

122 Map Incidence of invasive meningococcal disease by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; both confirmed and probable cases were included. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

123 Chapter 37. Mumps General overview for 2013 Two doses of mumps-containing vaccine are required to be fully immunized against mumps. Currently in Ontario, one dose of a combined measles, mumps, rubella (MMR) vaccine is given at 12 months of age, followed by a second dose at four to six years, in a combined measles, mumps, rubella, varicella (MMRV) vaccine. Individuals born in 1970 or later who have not acquired natural immunity through infection or who have not been vaccinated with two doses of mumps-containing vaccine are susceptible. 41 In Ontario, this includes a cohort of individuals born in 1991 or earlier who received only one dose of MMR and were less likely to be exposed to wild virus. 42 Sporadic cases of mumps continue to occur throughout the year, with peaks in incidence as a result of outbreaks. Incidence and comparison to Canada (Figure 37-1): Between 2000 and 2013, there were 852 confirmed and probable mumps cases in Ontario. Annual incidence fluctuated and ranged between a low of <0.1 cases per 100,000 in 2006 to a high of 2.6 cases per 100,000 in As seen in Figure 37-2, the incidence of sporadic cases of mumps in the province has remained relatively stable. Peaks in incidence seen between 2007 and 2011 were largely outbreak driven, with 82.2% of cases being linked to four separate outbreaks. In 2007, 29 cases were connected to outbreaks in Nova Scotia and New Brunswick, and in 2008, 324 cases were associated with an under-immunized religious community linked to concurrent outbreaks in the Netherlands and British Columbia. 43,44 Between 2009 and 2010, 166 cases were linked to outbreaks in the United States and Quebec, 45,46 and in 2011, 38 cases were linked to a Toronto cluster. In 2013, there were a total of 20 cases reported, including a small cluster of 6 cases occurring in a household of 8, where the acquisition exposure of the index case remains unknown. Overall, national incidence has followed a similar trend to that of Ontario, with the exception of years when mumps outbreaks have occurred in other provinces, most notably 2007 and Age and sex (Figure 37-3): In 2013, the highest agespecific incidence was observed in the year age group. Among adults aged years, many of whom would have received only one dose of mumpscontaining vaccine and are part of the susceptible cohort, incidence was 0.1 per 100,000. A slight predominance of male cases was observed (55.0%; 11/20); and among adults years of age, males account for 75.0% (6/8) of cases. No cases were reported among persons 50 years of age and older or among infants less than one year of age, a group not yet eligible to receive the MMR vaccine. Genotypes: Among the 20 cases reported in 2013, five were confirmed by Polymerase Chain Reaction (PCR). Among these, genotype G was most frequently isolated ( three cases), representing 60.0%. Genotypes K and I were isolated in each of the two remaining cases. Immunization: Of the cases reported in 2013, immunization status could be determined for 16 (80.0%); of these, nine were unimmunized, five had received one dose, and two had received two doses of mumps-containing vaccine. Among the nine cases who were unimmunized, eight were eligible to have received mumps-containing vaccine according to their age. Geographic distribution (Map 37-1): Only nine of the 36 public health units reported one or more cases of mumps in The highest incidence occurred in Peterborough County-City (1.4 cases per 100,000 population), Simcoe Muskoka District (1.3 cases per 100,000 population), and Northwestern (1.2 cases per 100,000 population); however, given the small number of cases, it should be noted that these rates are unstable. Reportable Disease Trends in Ontario,

124 Hospitalizations and deaths: In 2013, 10% (2/20) of cases were reported as hospitalized and no cases died. Remarkable features in 2013 Outbreaks have substantially influenced mumps epidemiology in Ontario in years when outbreaks occurred ( ). In 2013, the incidence of mumps was relatively low, consistent with the incidence of nonoutbreak years ( and ). Ontario continues to have individuals susceptible to infection, including those with incomplete immunization, and those travelling to endemic or outbreak areas. Receiving two doses of MMR vaccine is important for preventing mumps infection. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, Sept 2014 edition Figure Incidence of mumps: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; confirmed ( ) and probable ( ) cases were included. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

125 Figure Incidence of mumps by outbreak status: Ontario, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; confirmed ( ) and probable ( ) cases were included. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Incidence of mumps by age and sex: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; both confirmed and probable cases were included Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03].. Reportable Disease Trends in Ontario,

126 Map Incidence of mumps by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; both confirmed and probable cases were included. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

127 Chapter 38. Ophthalmia Neonatorum General overview for 2013 Incidence (Table 38-1): In 2013, two cases of ophthalmia neonatorum were reported in Ontario, corresponding to an incidence rate of 1.4 cases per 100,000 live births. From 2004 to 2013, a total of 34 cases of ophthalmia neonatorum were reported, an average of 3.4 cases per year over this period. The highest numbers of cases during this period were reported in 2004 and 2005, with six cases reported in each of those years. The cases in 2004 and 2005 did not have an agent identified in iphis. Thereafter, all cases of ophthalmia neonatorum were caused by Chlamydia trachomatis. No comparable national data are available as ophthalmia neonatorum is not nationally notifiable. Table Incidence of ophthalmia neonatorum: Ontario, Ontario rate Year Ontario cases per 100,000 live births Ontario Population: Live Births [ ], MOHLTC, IntelliHEALTH Ontario, extracted [2013/11/29]. Note: Live births data for 2012 and 2013 were unavailable at the time of data extraction; therefore, 2011 live births data were used to calculate rates for these years. Note: Ophthalmia neonatorum is not a nationally notifiable disease. Reportable Disease Trends in Ontario,

128 Chapter 39. Paralytic Shellfish Poisoning General overview for 2013 No cases of Paralytic Shellfish Poisoning have been identified in Ontario since it became reportable in December Reportable Disease Trends in Ontario,

129 Chapter 40. Paratyphoid Fever General overview for 2013 Incidence and comparison to Canada (Figure 40-1): Salmonella Paratyphi is the causative agent of paratyphoid fever and, along with Salmonella Typhi, is classified as typhoidal Salmonella (also known as enteric fever). In 2013, there were 41 confirmed cases of paratyphoid fever, representing an incidence rate of 0.3 cases per 100,000 population. National data for paratyphoid fever are not available, as it has not been distinguished from other types of salmonellosis at the national level since Age and sex (Figure 40-2): Incidence rates by age and sex do not show a clear trend, likely due to small case counts. Seasonal trends (Figure 40-3): In 2013, the number of cases was highest in February and March. Seasonal patterns are thought to reflect peak travel periods to endemic regions, such as Indochina and South Asia. 47 Geographic distribution (Map 40-1): The highest incidence rates were reported by Peel Region (0.9 cases per 100,000 population) and Toronto (0.6 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 36.6% (15/41) of cases and no deaths were reported. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, February 2013 edition Figure Incidence of paratyphoid fever: Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

130 Figure Incidence of paratyphoid fever by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Number of paratyphoid fever cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

131 Map Incidence of paratyphoid fever by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

132 Chapter 41. Pertussis General overview for 2013 Pertussis (also known as whooping cough) is an infection of the respiratory system caused by the Bordetella pertussis bacterium. It is endemic worldwide, and is known to cause prolonged cough, as well as serious complications and death among unimmunized young infants. 48 Vaccination plays a key role in reducing the risk of pertussis. 49 Under the publicly-funded immunization program, an acellular pertussis vaccine is given in combination with vaccines against diphtheria, tetanus, polio, and Haemophilus influenzae type b to infants at two, four, and six months of age, with a booster at 18 months. Additional booster doses of pertussiscontaining vaccine are administered at four to six years and 14 to 16 years of age. In 2011, a single booster dose of pertussis-containing vaccine was introduced for adults. Incidence and comparison to Canada (Figure 41-1): In 2013, 271 confirmed and probable cases of pertussis were reported in Ontario, representing an incidence rate of 2.0 cases per 100,000 population. Pertussis follows a cyclical trend, with peaks occurring every two to five years. 50 In Ontario, peaks in incidence occurred in 2006 and again in Rates in Ontario tended to be similar to national rates, with the notable exception of 2012, when there were a number of outbreaks in Canada. Seasonal trends (Figure 41-2): There is some seasonal variation in pertussis cases, with increases in incidence occurring in winter and summer months. In 2013, the number of cases was highest during the summer months of July and August. Age and sex (Figure 41-3): In 2013, the highest incidence rate of pertussis was observed among infants less than one year (36.6 cases per 100,000 population), followed by adolescents years (7.5 cases per 100,000 population) and children 1 4 years (7.1 cases per 100,000 population). Pertussis cases ranged in age from 13 days to 77 years, with a median age of 9.6 years. There were also more females (55.9%) than males (44.1%); the female predominance was particularly striking among adults years. Immunization: In 2013, immunization status could not be determined (i.e., unknown status or unknown dose number) for 70 out of 271 (25.8%) cases. However, over 50% (n=44) of adults with pertussis had an unknown immunization history. Among the 201 cases with known status, 53.7% were unimmunized. Among infants under one year with known immunization status, 80.5% were unimmunized (17 cases were under 2 months of age) and 12.2% had completed their primary series (three doses). Further, 49.2% of children 1 18 years of age and 37.5% of adults were not immunized. Overall, 93 cases with known immunization status had at least one dose of pertussis-containing vaccine. Geographic distribution (Map 41-1): Pertussis incidence varied across Ontario in Six public health units reported no cases in Elgin-St. Thomas (34.3 cases per 100,000 population) and Huron County (34.2 cases per 100,000 population) had the highest incidence of pertussis compared to other public health units. This was 17 times higher than the provincial rate. Hospitalizations and deaths: Approximately 8.9% (24/271) of cases in 2013 were reported as hospitalized. Of these, 87.5% (21/24) occurred in children. Among the 52 pertussis cases occurring in infants, 38.5% were hospitalized. No deaths were reported in Outbreak activity Ontario experienced a prolonged pertussis outbreak between November 2011 and April 2013 that originated in an under-immunized religious community. During this period, seven health units in Southwestern Ontario reported 443 confirmed and probable cases, representing an overall provincial rate of 6.1 cases per Reportable Disease Trends in Ontario,

133 100,000 population. The resurgence of pertussis in this outbreak was hypothesized to be due to both low vaccine coverage and waning immunity among young adolescents. 51 Given that pertussis is vaccinepreventable and poses a serious health threat for infants and young children, achieving vaccination coverage of at least 90% in infants with three doses of vaccines remains a priority worldwide. 49 Figure Incidence of pertussis: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; confirmed ( )and probable cases ( ) were included. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canada Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

134 Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct Number of cases Figure Number of pertussis cases by month: Ontario, Year and month of onset Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; confirmed ( )and probable cases ( ) were included. Figure Incidence of pertussis by age and sex: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Notes: Excludes one case of unknown sex. Both confirmed and probable cases were included. Reportable Disease Trends in Ontario,

135 Map Incidence of pertussis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]; both confirmed and probable cases were included. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

136 Chapter 42. Plague General overview for 2013 There were no cases of plague reported in Ontario in In the last 10 years, no cases have been reported in the province. Reportable Disease Trends in Ontario,

137 Chapter 43. Streptococcus pneumoniae, Invasive Invasive pneumococcal disease (IPD) is caused by the bacterium Streptococcus pneumoniae and is one of the 10 most burdensome infectious agents in Ontario. 22 In January 2005, a four-dose, 7-valent pneumococcal conjugate vaccine (PCV7) program was introduced as part of the publicly funded immunization program in the province for infants. This was replaced by a fourdose 10-valent vaccine (PCV10) program in October 2009 and subsequently, by a three-dose 13-valent vaccine (PCV13) program in November In 2012, a one-time catch-up dose of PCV13 was implemented for healthy children under three years and for children at higher risk for IPD under five years. Finally, a one dose 23-valent pneumococcal polysaccharide vaccine (PPV23) has been universally available for adults 65 years and older since General overview for 2013 Incidence and comparison to Canada (Figure 43-1): There were 1,036 confirmed cases of IPD in This represents an overall incidence of 7.7 cases per 100,000 population, which was lower than the 2012 incidence of 9.5 cases per 100,000 population. Rates in Ontario tended to be similar to, or lower than, national rates between 2004 and Age and sex (Figure 43-2): The highest incidence of IPD was observed in adults 65 years and older (22.9 cases per 100,000 population), followed by children 1 4 years (11.5 cases per 100,000 population). Adults 50 to 64 years had the third highest rate in the province (10.0 cases per 100,000 population). Overall, males accounted for 54.8% of all cases, however,males consistently had higher rates of disease than females in every age group except infancy (i.e., under one year). Seasonal trends (Figure 43-3): As with other infectious diseases, IPD follows a seasonal pattern, with an increased incidence in the colder months and a decreased incidence during the summer. Some evidence suggests that this seasonal pattern is influenced by influenza virus enhancing the risk of bacterial invasion in colonized individuals. 53 Immunization: Immunization status could not be determined (i.e., unknown status or unknown dose) for 588 out of 1,036 (56.8%) cases in Of those with known status, 60.7% (272/448) were unimmunized. This proportion did not vary substantially by age. Among cases under five years of age, 34.3% (12/35) were unimmunized, and among adults greater than 65 years, 48.4% (105/217) were not immunized. A total of 176 cases (39.3%) had at least one dose of vaccine against IPD. These estimates should be interpreted with caution given the extent of missing information. Efforts are underway to improve the data quality. Serotypes (Figure 43-4): In 2013, serotypes were known for 79.2% of all cases (821/1,036). Among children less than five years of age, a decrease in incidence due to PCV7 serotypes (consisting of serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F) was observed between Incidence also decreased for PCV13 serotypes (consisting of PCV7 serotypes plus 1, 3, 5, 6A, 7F, and 19A) after Reductions in the incidence for PCV7 and PCV13 serotypes were also observed among adults 65 years and older through the six-year period and after 2010, respectively, suggesting a herd effect in age groups not targeted for pneumococcal conjugate immunization. In contrast, incidence due to serotypes unique to PPV23 demonstrated a consistent increase among adults 65 years and older since Geographic distribution (Map 43-1): Incidence of IPD varied throughout the province. Only one health unit did not report any cases in Northwestern had the highest incidence of IPD in Ontario at 29.6 cases per 100,000 population. This is consistent with findings that IPD is a major health concern in the northern parts of Canada. 54 Reportable Disease Trends in Ontario,

138 Hospitalizations and deaths: In 2013, 72.9% of cases were reported as hospitalized. Among persons less than five years and over 65 years, 66.2% and 75.6% were reported as hospitalized. The overall case fatality ratio was 11.6%. Among adults 65 years and older, the case fatality ratio was 10.8%. Figure Incidence of invasive pneumococcal disease: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canada Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Figure Incidence of invasive pneumococcal disease by age and sex: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes one case of unknown sex. Reportable Disease Trends in Ontario,

139 Figure Number of invasive pneumococcal disease cases by month: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. 5-Yr Average: Represents the five-year ( ) average of the number of cases with an episode date in the corresponding month. Figure Invasive pneumococcal disease incidence by age group and vaccine serotype (ST) Group: Ontario, *Note: Additional PPV23 and non-vaccine-preventable serotypes not shown. Nongroupable/typeable and unspecified serotypes excluded. *Note: Non-vaccine-preventable serotypes not shown. Nongroupable/typeable and unspecified serotypes excluded Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

140 Map Incidence of invasive pneumococcal disease by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

141 Chapter 44. Poliomyelitis (polio) General overview for 2013 Under the publicly funded immunization program in Ontario, inactivated polio vaccine (IPV) is administered to children in combination with vaccines against diphtheria, tetanus, pertussis, and Haemophilus influenzae type b at two, four, six, and 18 months of age. 13 A booster dose of IPV-containing vaccine is given at 4 6 years of age. 13,55 Incidence and comparison to Canada: There were no cases of polio reported in Ontario in As a result of successful polio immunization programs, Canada was certified polio-free in 1994 by the World Health Organization. 55 Highlights Although polio remains endemic in only three countries (Afghanistan, Pakistan, and Nigeria), cases were reported in Cameroon, Ethiopia, Kenya, Somalia, and Syria in Despite Canada s polio-free status, there still remains a risk of importation of cases from countries where endemic transmission of polio still occurs. Reportable Disease Trends in Ontario,

142 Chapter 45. Psittacosis/Ornithosis General overview for 2013 There were no cases of psittacosis/ornithosis reported in Ontario in In the last 10 years, two confirmed cases have been reported in the province. Reportable Disease Trends in Ontario,

143 Chapter 46. Q Fever General overview for 2013 Incidence and comparison to Canada (Figure 46-1): In Ontario in 2013, there were 15 confirmed cases of Q fever, representing an incidence rate of 1.1 cases per 1,000,000 population. Since 2011, the number of confirmed cases reported in Ontario has increased. No comparable national data is available as Q fever is not a nationally notifiable disease. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, June 2012 edition Hospitalizations and deaths: Hospitalization was reported for 26.7 % (4/15) of cases and no deaths were reported. Figure Incidence of Q fever: Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Discrepancies in the rates graphed and presented in the data table for this figure may occur due to rounding. Reportable Disease Trends in Ontario,

144 Chapter 47. Rabies General overview for 2013 There were no cases of rabies reported in Ontario in The last confirmed case of rabies acquired in Ontario was in Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, September 2012 edition Middleton D, Johnson KO, Rosatte RC, Hobbs JL, Moore SR, Rosella L, et al. Human rabies postexposure prophylaxis and animal rabies in Ontario, Canada, Zoonoses Public Health [Epub ahead of print]. Reportable Disease Trends in Ontario,

145 Chapter 48. Rubella and Congenital Rubella Syndrome General overview for 2013 Both indigenous rubella and congenital rubella syndrome (CRS) have been eliminated in Canada. Under the guidance of the Pan American Health Organization, countries in the Americas have been documenting the elimination of these vaccine-preventable diseases. 35 Rubella vaccine is administered in combination with vaccines for mumps, measles, and varicella (MMR and MMRV vaccines) in Ontario as part of the publicly funded immunization program. A single dose of rubellacontaining vaccine is required to be considered fully immunized against rubella. A single dose of MMR vaccine is recommended for susceptible non-pregnant women since rubella during pregnancy can result in CRS. 57 Additional sources of information Lim GH, Deeks SL, Fediurek J, Gubbay J, Crowcroft NS. Documenting the elimination of measles, rubella, and congenital rubella syndrome in Ontario: Can Commun Dis Rep. 2014;40(8) Incidence and comparison to Canada (Figure 48-1 and Figure 48-2): In 2013, one confirmed case of rubella was reported in Ontario, representing an incidence rate of 0.1 cases per 1,000,000 population. The annual incidence rate of rubella in Ontario ranged between 0.0 and 24.9 cases per 1,000,000 population since 2003, with the highest rate reported in 2005, which was due to a rubella outbreak in an under-immunized community that was opposed to immunization in Southwestern Ontario. 57 No cases of CRS were reported in The annual incidence rate of CRS ranged from 0.0 to 15.1 cases per 1,000,000 population between 2003 and Except for 2005, Ontario and Canadian incidence of rubella and CRS follow a similar trend with low incidence. The single case of rubella in 2013 occurred in an adult female who was vaccinated with a single dose of rubellacontaining vaccine. The case was imported, being associated with travel to Japan, and was genotype 2B. Reportable Disease Trends in Ontario,

146 Figure Incidence of rubella: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canada Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Figure Incidence of congenital rubella syndrome: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Live Births [ ], MOHLTC, intellihealth Ontario, extracted [2013/11/29]; 2011 data used as denominator for 2012 and 2013 Canada Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

147 Chapter 49. Salmonellosis General overview for 2013 Incidence and comparison to Canada (Figure 49-1): In Ontario in 2013, there were 2,501 confirmed cases of salmonellosis, representing an incidence rate of 18.5 cases per 100,000 population. Rates in Ontario from 2008 to 2011 have been comparable to the Canadian rates and were below Canadian rates in Age and sex (Figure 49-2): The highest incidence rates were observed in the 0 4 and 5 9 year age groups. There was little difference in the incidence rates by sex, with the exception of the and year age groups. Seasonal trends (Figure 49-3): Salmonellosis tends to follow a seasonal pattern, with the majority of cases reported in the summer months due to increased frequency of outdoor activities, social gatherings with food, and warmer temperatures that promote pathogen growth. 14 Serotypes (Table 49-1): S. Enteritidis (31.7%), S. Heidelberg (12.8%), and S. Typhimurium (12.5%) were the most common serotypes. It is expected that the serotypes of some salmonellosis cases are misclassified, or left as unspecified, resulting in under-reporting of certain Salmonella serotypes. Geographic distribution (Map 49-1): The highest incidence rates were reported by Grey Bruce (28.9 cases per 100,000 population), Huron County (27.4 cases per 100,000 population), and Haldimand-Norfolk (25.5 cases per 100,000 population). Outbreak activity In 2013, there were several cluster and outbreak investigations involving various serotypes of Salmonella. Two provincial Salmonella investigations occurred, one for S. Typhimurium and one for S. Enteritidis. In March, an Ontario Outbreak Investigation Coordination Committee was activated to investigate S. Typhimurium cases with a matching pulse-field gel electrophoresis pattern. A total of 31 confirmed cases were associated with the outbreak. The investigation implicated a food premise as the potential source. Also in March, a Public Health Alert was issued following notification of two cases of S. Enteritidis who travelled to a resort in the Dominican Republic in February, as part of a large trip involving some 600 students. In total, 13 cases of S. Enteritidis were linked to the outbreak. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, May 2012 edition Middleton D, Savage R, Tighe MK, Vrbova L, Walton R, Whitfield Y, et al. Risk factors for sporadic domestically acquired Salmonella serovar Enteritidis infections: a case-control study in Ontario, Canada, Epidemiol infect. 2014;142(7): Varga C, Middleton D, Walton R, Savage R, Tighe MK, Allen V, et al. Evaluating risk factors for endemic human Salmonella Enteritidis infections with different phage types in Ontario, Canada using multinomial logistic regression and a case-case study approach. BMC Public Health. 2012;12:866. Hospitalizations and deaths: Hospitalization was reported for 10.7 % (267/2,501) of cases. Death was reported for 0.2 % (5/2,501) of cases. Reportable Disease Trends in Ontario,

148 Figure Incidence of salmonellosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: National data includes paratyphoid fever cases. Figure Incidence of salmonellosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

149 Figure Number of salmonellosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Table Salmonellosis cases by Salmonella serotype: Ontario, 2013 Cases Salmonella Serotypes n % S. Enteritidis S. Heidelberg S. Typhimurium S. ssp. enterica 4,[5],12:i: S. Thompson S. Newport Other Unspecified serotype Total Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/16]. Reportable Disease Trends in Ontario,

150 Map Incidence of salmonellosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

151 Chapter 50. Shigellosis General overview for 2013 Additional sources of information Incidence and comparison to Canada (Figure 50-1): In 2013, there were 251 confirmed cases of shigellosis, representing an incidence rate of 1.9 cases per 100,000 population. Since 2005, rates in Ontario have been below the Canadian rates. PHO s Monthly Infectious Diseases Surveillance Report, August 2014 edition Age and sex (Figure 50-2): The highest incidence rates were observed in the 0 4 and 5 9 year age groups (3.6 cases per 100,000 population and 2.9 cases per population, respectively). Although individuals from all age groups are susceptible to shigellosis infection, the literature suggests that most cases occur among children under the age of Higher incidence rates were observed among females under 20 years of age compared to males. However, among older age groups, incidence rates were higher among males. Seasonal trends (Figure 50-3): While shigellosis is thought to be more common in summer months, a seasonal trend in 2013 was not observed. This may in part be due to travel-related cases that occur during the winter months. 59 Serotypes (Table 50-1): S. sonnei (51.8%) and S. flexneri (38.3%) were the most frequently reported serotypes. Geographic distribution (Map 50-1): The highest incidence rates were reported by Eastern Ontario (4.4 cases per 100,000 population), Toronto (3.5 cases per 100,000 population), and Ottawa (3.1 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 12.7 % (32/251) of cases and no deaths were reported. Reportable Disease Trends in Ontario,

152 Figure Incidence of shigellosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure Incidence of shigellosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

153 Figure Number of shigellosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Table Shigellosis cases by Shigella serotype: Ontario, 2013 Cases Shigella Serotype n % S. sonnei S. flexneri S. boydii S. dysenteriae Unspecified serotype Total Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/09/15]. Reportable Disease Trends in Ontario,

154 Map Incidence of shigellosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

155 Chapter 51. Smallpox General overview for 2013 Incidence and comparison to Canada: Smallpox has been eradicated from the world. No confirmed cases have been reported in the province or elsewhere in the world since the global eradication of smallpox was confirmed by the World Health Organization in Reportable Disease Trends in Ontario,

156 Chapter 52. Syphilis, Infectious General overview for 2013 Incidence (Figure 52-1): In 2013, 721 cases of infectious syphilis cases were reported in Ontario, corresponding to an incidence rate of 5.3 cases per 100,000 population. Of the 721 cases of infectious syphilis, 28.2% of cases (203/721) were primary syphilis, 36.9% of cases (266/721) were secondary syphilis, 33.6% of cases (242/721) were early latent syphilis, and 1.4% of cases (10/721) were infectious neurosyphilis. In 2013, there were no cases of congenital syphilis reported. The reported incidence of infectious syphilis increased by 71.4%, from 3.5 cases per 100,000 population in 2008 to 6.0 cases per 100,000 population in The increase in 2009 is primarily attributable to cases of infectious syphilis among men who have sex with men (MSM) Since 2009, the reported incidence of infectious syphilis in Ontario remained stable at around six cases per 100,000 population, before a decrease was observed in The annual incidence rates for Ontario are not directly comparable to Canadian rates because the latter includes cases of infectious, non-infectious and unspecified syphilis. Age and sex (Figure 52-2): In 2013, the reported incidence of infectious syphilis was 17 times higher among males (10.2 cases per 100,000 population) than females (0.6 cases per 100,000 population), with males accounting for 94.2% (679/721) of all cases reported in Ontario (data not shown). Incidence was highest in the year age group among males, with a rate of 23.9 cases per 100,000 population, and among females, incidence was highest in the and age groups, with rates of 1.5 cases per 100,000 population in each group. Geographic distribution (Map 52-1): In 2013, cases of infectious syphilis were reported in 77.8% (28/36) of Ontario s public health units. The highest incidence rates were reported in Toronto, Hamilton, and Windsor-Essex County public health units, with rates of 16.4, 7.9, and 4.0 cases per 100,000 population, respectively. Highlights HIV co-infection is common among infectious syphilis cases. 66 Among cases of infectious syphilis reported in 2013, 36.1% (260/721) were determined to be coinfected with HIV; these cases were either diagnosed with HIV prior to, or within one year of, their syphilis diagnosis. Some infectious syphilis cases may not know their HIV status, or may have tested anonymously, and therefore, the number of co-infected cases may be higher. Additional methodological issues Cases of syphilis may be under-reported, or there may be delays in case reporting, due to challenges associated with staging the infection. Staging the infection at diagnosis can be complex, particularly among those with early or previous infection, which can result in misclassification. 67 In addition, syphilis staging may take up to several months, resulting in a lag in case reporting to public health units. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, June 2013 Reportable Disease Trends in Ontario,

157 Figure Incidence of syphilis, infectious: Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: National data excluded as it does not distinguish between infectious and non-infectious syphilis. Figure Incidence of syphilis, infectious by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

158 Map Incidence of syphilis, infectious by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

159 Chapter 53. Tetanus General overview for 2013 Incidence and comparison to Canada (Figure 53-1): There were two confirmed cases of tetanus reported in Ontario in Both cases were clinical cases and were in the year age group. Annual incidence in Ontario was comparable to national figures over the past 20 years. Hospitalizations and deaths: Of the two cases reported in 2013, one case was reported as hospitalized and no cases died. Immunization: Both of the confirmed cases were reported as being partially immunized. Under Ontario s publicly funded immunization program, tetanus toxoid-containing vaccine is routinely administered in combination with vaccines against diphtheria, pertussis, polio, and Haemophilus influenzae type b to children at two, four, six, and 18 months of age. 13,68 Subsequently, booster doses of tetanus toxoidcontaining vaccines are administered at four to six years and 14 to 16 years of age. 13,68 A booster dose is recommended for adults every 10 years for continued protection. Figure Incidence of tetanus: Ontario and Canada, Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population [ ]: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Ontario Population [ ]: MOHLTC, intellihealth Ontario, extracted [2013/09/16]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Nunavut did not report on tetanus in Denominators are adjusted for rate calculations. Reportable Disease Trends in Ontario,

160 Chapter 54. Transmissible Spongiform Encephalopathy General overview for 2013 Incidence and comparison to Canada: Until December 4, 2013, four prion diseases in Ontario were reportable under the category of transmissible spongiform encephalopathy: Creutzfeldt-Jakob Disease (CJD), including sporadic, familial, iatrogenic, and variant types; Gerstmann-Sträussler-Scheinker Syndrome (GSS); Fatal Familial Insomnia (FFI); and Kuru. GGS, FFI and Kuru were removed from Ontario s Reportable Disease List on December 4, Although CJD is reportable in Ontario, clinicians typically report cases to the Canadian CJD Surveillance System (CJDSS), which is maintained by the Public Health Agency of Canada. As a result, CJD cases are not consistently reported to local public health units, and therefore, some cases are not entered in iphis. Over the five-year period from 2009 to 2013, the CJDSS was notified of 86 deaths in Ontario due to CJD; 80 were classified as sporadic CJD, five as familial CJD (including two deaths due to GSS), and one as variant CJD. 69 There were no reported cases of iatrogenic CJD in Ontario reported to CJDSS over this period. This count was similar to the 84 CJD deaths reported to the CJDSS in the preceding five-year period from 2004 to Deaths reported through the CJDSS were attributed to definite and probable cases of CJD according to national case definitions. 70 Additional methodological issues Under-reporting of Ontario CJD cases in iphis limits examination of risk factors or further case description using iphis data. For example, the Ontario CJD case counts available from the CJDSS for are 62.3% higher than the 53 confirmed and probable CJD cases reported in iphis for the same time period. Prion diseases are universally fatal, and deaths may be under investigation for long periods of time, which may lead to reporting delays. Investigation relies on the cooperation of public health, physicians, health care institutions and family members. Of note, clinical diagnosis requires examination of affected brain tissue, often best obtained at autopsy. 71 To compare case counts from the CJDSS and iphis, cases classified as confirmed and probable according to the national case definition were considered to be equivalent to cases classified as confirmed and probable according to the provincial case definition. 70,72 Reportable Disease Trends in Ontario,

161 Chapter 55. Trichinosis General overview for 2013 There were no cases of trichinosis reported in Ontario in In the last 10 years, four confirmed cases have been reported in the province. Reportable Disease Trends in Ontario,

162 Chapter 56. Tuberculosis General overview for 2013 Incidence and comparison to Canada (Figure 56-1): In 2013, a total of 630 active tuberculosis (TB) cases were reported in Ontario, corresponding to an incidence rate of 4.7 cases per 100,000 population. From 2004 to 2012, the annual incidence rate of reported active TB cases in Ontario decreased from a high of 6.0 cases per 100,000 population in 2004 to 4.6 cases per 100,000 population in Over this same time period, incidence rates of active TB in Ontario were higher than the Canadian rate from and in Age and sex (Figure 56-2): The overall reported incidence of active TB was higher for males than females in 2013, at 5.1 and 4.2 cases per 100,000 population, respectively. Males accounted for 54.3% (342/630) of cases. Cases ranged in age from less than one year to 92 years, with a median age of 47 years (data not shown). The highest overall age-specific incidence rates of active TB were reported among adults 70 years of age and over, followed by adults between 20 and 49 years of age. In the older age groups (50 years of age and over), the reported incidence rate among males consistently exceeded that of females, reaching nearly double the rate in females in the 70 and older age group (13.0 cases vs. 6.8 cases per 100,000 population). Country of birth (Table 56-1): Individuals born outside of Canada accounted for the largest proportion of active TB cases reported in Ontario in 2013 (88.3%, 556/630 cases). The top five countries of birth among TB cases reported from 2008 to 2013 were India (18.2%, 696/3,817), the Philippines (14.5%, 555/3,817), China (9.2%, 350/3,817), Vietnam (5.4%, 208/3,817) and Pakistan (4.0%, 153/3,817). These countries are among the 27 high multidrug-resistant TB (MDR-TB) burden countries identified by the World Health Organization. 73 In 2013, Public Health Ontario Laboratories (PHOL) identified 16 MDR-TB cases and no extensively drugresistant TB (XDR-TB) cases (data not shown); however, this may include some cases with an initial TB diagnosis prior to Although the incidence of MDR-TB and XDR-TB is relatively uncommon at present in Ontario, 74 rates may increase with continued immigration from high MDR-TB burden countries. Geographic distribution (Map 56-1): In 2013, the highest incidence rates of active TB were reported in Northwestern, Toronto, and Peel Regional public health units, with 17.3, 10.3, and 9.2 cases per 100,000 population, respectively. Toronto and large urban centres in Peel Region tend to attract new immigrants and have established communities of residents originating from countries with a high prevalence of TB. 75 Therefore, one of the potential reasons for the increased burden of active TB in these public health units may be the relatively higher proportion of immigrants from high-incidence TB countries. The number of TB cases reported in Northwestern (n=14) in 2013 was unusual, because from 2008 to 2012, between one and six cases were reported each year (data not shown). Deaths: Of active TB cases diagnosed in 2013, 6.3% (40/630) were reported as fatal. Highlights Northwestern had the highest rate of tuberculosis in These cases were predominantly among First Nations (13/14; 92.9%). Of the 14 cases, nine were male and five were female. The cases ranged in age from seven to 78 years of age. Six of the cases were identified as having identical genotypes to other TB cases in the Ontario Universal Typing of Tuberculosis (OUT-TB) program, while the eight remaining cases do not have information in OUT-TB. Reportable Disease Trends in Ontario,

163 Additional methodological issues Although most cases of active TB reported in Ontario are in persons born outside Canada, First Nations peoples, particularly those living on-reserve, represent another population which is disproportionately affected by TB. 76 However, since TB cases among First Nations peoples living on-reserve fall within federal jurisdiction, it is likely that cases in this population are under-reported in Ontario. Furthermore, those who live on or off-reserve may not be identified as being First Nations in iphis due to incomplete origin information. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, March 2014 edition PHO s Monthly Infectious Diseases Surveillance Report, March 2012 edition Figure Incidence of tuberculosis: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

164 Figure Incidence of tuberculosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

165 Table Tuberculosis cases by country of birth: Ontario, Country of Birth Born Outside Canada Diagnosis Year India Philippines China Vietnam Pakistan Somalia Sri Lanka Hong Kong Ethiopia Bangladesh Other Unknown * Total born outside Canada Born in Canada Inuit Non-Aboriginal Registered/Status Indian, Other Aboriginal Total born in Canada Origin unknown/missing TOTAL Notes: * Unknown: includes cases born outside of Canada but for which the country of birth is not provided or is unknown. Registered/Status Indian may include cases that are classified as 'other aboriginal'. Other Aboriginal may include cases that are classified as 'other aboriginal, or Aboriginal unknown. Total Reportable Disease Trends in Ontario,

166 Map Incidence of tuberculosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

167 Chapter 57. Tularemia General overview for 2013 There were no cases of tularemia reported in Ontario in In the last 10 years, six confirmed cases have been reported in the province. Reportable Disease Trends in Ontario,

168 Chapter 58. Typhoid Fever General overview for 2013 Incidence and comparison to Canada (Figure 58-1): In Ontario in 2013, there were 59 confirmed cases of typhoid fever, representing an incidence rate of 0.4 cases per 100,000 population. Since 2004, rates in Ontario have been below the Canadian rates. Age and sex (Figure 58-2): The highest incidence rates were observed in the 0 4 and 5 9 year age groups. In these age groups, there were 0.8 cases per 100,000 population and 1.1 cases per 100,000 population, respectively. Incidence rates by sex do not show a clear trend, likely due to small case counts. Geographic distribution (Map 58-1): The highest number of cases were reported by Peel Region (27 cases), and Toronto (14 cases). Hospitalizations and deaths: Hospitalization was reported for 42.4 % (25/59) of cases and no deaths were reported. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, February 2013 edition Seasonal trends (Figure 58-3): Increases in disease due to typhoid fever are known to occur during peak travel periods, however, a seasonal trend was not observed in Ontario in Figure Incidence of typhoid fever: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Reportable Disease Trends in Ontario,

169 Figure Incidence of typhoid fever by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Number of typhoid fever cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

170 Map Incidence of typhoid fever by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

171 Chapter 59. Varicella (Chickenpox) General overview for 2013 A vaccine against varicella was authorized for use in Canada in December In September 2004, a publicly funded program was introduced in Ontario for children at 15 months of age without a history of chickenpox. A two-dose varicella program was introduced in August 2011, with the first dose recommended at 15 months of age, and the second dose at four to six years of age, given in combination with measles, mumps, and rubella vaccine (MMRV). 13 All children born on, or after, January 1, 2000 were also eligible to receive a second dose of publicly funded varicella vaccine. 13 In Ontario, cases of varicella are reported individually, and in aggregate numbers through iphis. 78 Prior to 2006, aggregate cases were reported in the Reportable Disease Information System (RDIS). Individually-reported cases represent the more severe spectrum of disease because laboratory-confirmed cases, hospitalized cases, and cases with complications, including death, are required to be reported individually. 79 In addition, all health units are requested to report monthly aggregate counts of varicella, regardless of whether any cases were observed in a given month. Aggregate counts represent the total number of cases occurring in a health unit jurisdiction, broken down by predefined age groups. Aggregate counts do not contain individual case details (e.g., immunizations, hospitalizations, etc.), and may include cases that have been entered as individual cases, as well as those that do not meet the criteria for individual case reporting. 80 Reports received from health care providers, schools, child care facilities, and parents are included in aggregate varicella counts. This chapter primarily presents varicella data reported as aggregate cases. Aggregate counts from 2005 and 2006 were excluded due to data incompleteness and the transition from RDIS to iphis (aggregate reporting of varicella in iphis began in late 2006). Incidence and comparison to Canada (Figure 59-1): In 2013, there were 3,007 aggregate cases of varicella reported in Ontario, representing an incidence of 22.2 cases per 100,000 population. The annual reported incidence of aggregate varicella in Ontario was higher than the Canadian incidence in all years except The Canadian rate does not include counts from all provinces and territories (see notes for Figure 59-1). In addition, there were 342 cases of varicella reported at the individual level in 2013, for an incidence of 2.5 cases per 100,000 population. Hospitalizations and deaths: Of the 342 individuallyreported cases in 2013, 22 cases (6.4%) were reported as hospitalized and one case was reported as fatal, resulting in a case fatality ratio of 0.3%. The case fatality ratio would be 0.03% if considering the total number of aggregate cases reported rather than only those cases reported individually. Age (Figure 59-2): In 2013, the highest incidence of varicella was observed in the 5 9 year age group with cases per 100,000 population (1,247 cases), accounting for 42.0% of all cases with known age group, despite 5 9 year olds accounting for only 5.4% of the population in The year age group was associated with the second highest incidence, followed by the 1 4 year age group. Infants under one year of age, who are too young to be vaccinated, had the lowest age-specific incidence among children under 15 years of age. The median age of individually reported varicella cases was 13.3 years (ranging from less than one month to 79.9 years of age). Seasonal trends (Figure 59-3): Based on the five-year average, the number of varicella cases were highest in spring (peaking in May), and declined over summer, with the lowest counts reported in August. Cases in 2013 showed a similar seasonal trend, with the highest and lowest number of cases observed in April and August, respectively. Reportable Disease Trends in Ontario,

172 Geographic distribution (Map 59-1): The public health unit-specific incidence rates ranged widely from 0.0 to cases per 100,000 population in It is unclear as to whether the absence of aggregate cases observed in seven health units (Durham Region, Halton Region, Haldimand-Norfolk, Lambton County, Middlesex- London, Perth District, and Timiskaming) reflects a true absence of disease in those regions or a lack of reporting. Four of these seven health units (Durham Region, Halton Region, Middlesex-London, and Perth District) reported individual cases. Additional methodological issues Aggregate varicella data are useful in identifying trends in varicella incidence; however, these data are prone to substantial under-reporting and lack precision. Although the degree of under-reporting is not known, it is likely that the burden of varicella in Ontario is substantially underestimated. Additionally, aggregate cases cannot be reconciled with individual-level data (e.g., laboratory results, immunization data), and may include some duplicate cases reported from more than one source, as well as misclassified cases (e.g., herpes zoster cases). Aggregate varicella cases are included in the analysis only if they met the following conditions: Only those counts that have the Outbreak Classification field entered as CONFIRMED. 2. Only those counts that have the Role field entered as OTHER. For those varicella outbreaks that have a missing Reported Date field, the Outbreak Name field is used to update the missing date field to minimize the loss of cases due to incomplete data. Reportable Disease Trends in Ontario,

173 Figure Incidence of aggregate varicella (chickenpox): Ontario and Canada, Ontario Cases [ ]: MOHLTC, Ontario Public Health Portal, accessed [2012/05/24]. Ontario Cases [ ]: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Note: Aggregate counts for 2005 are not available. Aggregate counts for 2006 are incomplete as the reporting began in late Ontario Population [ ]: MOHLTC, intellihealth Ontario, extracted [2013/09/16]. Ontario Population [ ]: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note: Some provinces and territories did not report on varicella in certain years; their populations have been removed for national rate calculations. a. Manitoba, Ontario and Quebec did not report on varicella in b. British Columbia, Manitoba and Quebec did not report on varicella in c. British Columbia, Manitoba, Quebec and Saskatchewan did not report on varicella in d. British Columbia, Manitoba and Quebec did not report on varicella in e. British Columbia, Manitoba, Quebec and Saskatchewan did not report on varicella in Nunavut did not report on varicella in Ontario did not report any cases of varicella in 2004; however, Ontario population is included in the denominator as there was no specific note from Ontario. f. British Columbia, Manitoba, Nova Scotia, Quebec, Saskatchewan, Nunavut and Yukon Territories did not report on varicella in g. British Columbia, Manitoba, Nova Scotia, Ontario, Quebec, Saskatchewan, Nunavut and Yukon Territories did not report on varicella in Reportable Disease Trends in Ontario,

174 Figure Incidence of aggregate varicella (chickenpox) by age group: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Note: Excludes 37 cases of unknown age group. Figure Incidence of aggregate varicella (chickenpox) by month: Ontario, 2013 Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. 5-Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

175 Map Incidence of aggregate varicella (chickenpox) by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Cases: MOHLTC, integrated Public Health Information System (iphis) database, extracted [2014/07/16]. Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

176 Chapter 60. Verotoxin-producing E. coli infection indicator conditions, including Hemolytic Uremic Syndrome General overview for 2013 Incidence and comparison to Canada (Figure 60-1): In Ontario in 2013, there were 143 confirmed cases of verotoxin-producing E. coli infections (VTEC), representing an incidence rate of 1.1 cases per 100,000 population. Between 2004 and 2013, the Ontario incidence rate for VTEC declined and remained below Canadian rates. Age and sex (Figure 60-2): The highest incidence rates were observed among young children under 10 years of age and older adults, in particular adults 60 years of age and older. The increased likelihood of parents to seek health care for their young children, as well as the challenges of maintaining good hygiene practices for young children, may account for the higher incidence observed among the younger age groups. With the exception of children under 10 years of age, a difference in incidence rates by sex was not observed. Seasonal trends (Figure 60-3): VTEC tends to follow a seasonal pattern, with an increase from May to October. In 2013, however,a clear seasonal increase was not observed. Serotypes: Of the 131 confirmed VTEC cases in 2013 where serotype information was available, 121 (92.4 %) were E. coli O157:H7. However, E. coli O157 is likely over-represented in Ontario surveillance data because non-o157 VTEC is not routinely tested in front-line laboratories. Testing for non-o157 VTEC must be explicitly requested, and can be requested from the Public Health Ontario Laboratories if clinically suspected, including in cases of hemolytic uremic syndrome or severe bloody diarrhea. Geographic distribution (Map 60-1): The highest incidence rates were reported by Oxford County (5.4 cases per 100,000 population) and Perth District (5.1 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 32.9 % (47/143) of cases and no deaths were reported. Outbreak activity In 2013, there were several VTEC cluster and outbreak investigations. In January 2013, a national investigation involving 13 cases from Ontario implicated lettuce as the likely source of the outbreak. 82 In September 2013, an outbreak investigation identified beef burgers as the cause of a cluster of 12 E. coli O157:H7 cases, leading to a voluntary recall of product by the manufacturer. 83 In June 2013, a national investigation of a cluster of VTEC cases, five of which were from Ontario, failed to identify the source, although leafy greens were suspected as the potential cause of illness. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, July 2013 edition Tataryn J, Morton V, Cutler J, McDonald L, Whitfield Y, Billard B, et al. Outbreak of E. coli O157:H7 associated with lettuce served at fast food chains in the Maritimes and Ontario, Canada, Dec Can Commun Dis Rep. 2014;40(S1). PHO's Labstract on Non O157 Shiga Toxin Producing E coli (STEC) Laboratory Testing Guidelines Reportable Disease Trends in Ontario,

177 Figure Incidence of VTEC: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Figure Incidence of VTEC by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

178 Figure Number of VTEC cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

179 Map Incidence of VTEC by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

180 Chapter 61. West Nile Virus Illness General overview for 2013 Incidence and comparison to Canada (Figure 61-1): In Ontario in 2013, there were 50 confirmed and seven probable cases of West Nile Virus (WNV), representing a combined incidence rate of 0.4 cases per 100,000 population. Age and sex (Figure 61-2): The highest incidence rates were observed in older adults in the 50 59, 60 69, and 70+ year age groups. Incidence rates by sex do not show a clear trend, likely due to small case counts. Additional sources of information PHO s Monthly Infectious Diseases Surveillance Report, December 2012 edition PHO s Weekly WNV Surveillance Reports PHO s Annual Vector-Borne Disease 2013 Summary Report PHO s Guide for Public Health Units: Considerations for Adult Mosquito Control Seasonal trends (Figure 61-3): Cases of West Nile Virus are predominantly reported during the warmer months from July to September. As WNV is transmitted by mosquitoes, and their lifecycle is heavily influenced by weather, year-to-year fluctuations in reported cases are expected. Geographic distribution (Map 61-1): C. pipiens/restuans, the principal mosquito vector in Ontario, is an urban-dwelling mosquito with a preference for catch basins during its early stages of development. As a consequence, the majority of human WNV cases are reported in urban settings. The highest number of cases was reported in Toronto (12 cases). The highest incidence rates, however, were reported by Chatham-Kent (2.8 cases per 100,000 population) and Huron County (3.4 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 33.3 % (19/57) of cases and death was reported for 3.5 % (2/57) of cases. Reportable Disease Trends in Ontario,

181 Figure Incidence of Confirmed and Probable West Nile Virus Illness: Ontario and Canada, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Canadian Rates: Public Health Agency of Canada, Canadian Notifiable Disease Section, received by PHO [2014/07/15]; national data available up to Note that national WNV data are the sum of both probable and confirmed cases; provincial breakdown of WNV data were not available. Figure Incidence of West Nile Virus Illness by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

182 Figure Number of West Nile Virus Illness cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

183 Map Incidence of West Nile Virus Illness by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

184 Chapter 62. Yellow Fever General overview for 2013 There were no cases of yellow fever reported in Ontario in No other cases have been reported provincially in the last 10 years. Reportable Disease Trends in Ontario,

185 Chapter 63. Yersiniosis General overview for 2013 Incidence (Figure 63-1): In Ontario in 2013, there were 175 confirmed cases of yersiniosis, representing an incidence rate of 1.3 cases per 100,000 population. Since 2004, the incidence rate has declined. The reason for the decline is not known. No comparable national data are available as yersiniosis is not a nationally notifiable disease. Age and sex (Figure 63-2): The highest overall incidence rates were observed in the 0 4 and 5 9 year age groups (6.6 cases per 100,000 population and 3.4 cases per 100,000 population, respectively). Rates were higher among males, with the exception of the and year age groups. Seasonal trends (Figure 63-3): Although a seasonal increase for yersiniosis tends to occur during the winter in temperate climate regions, a seasonal trend was not observed in Ontario in Geographic distribution (Map 63-1): The highest incidence rates were reported by Thunder Bay District (3.2 cases per 100,000 population) and Grey Bruce (3.1 cases per 100,000 population). Hospitalizations and deaths: Hospitalization was reported for 5.1 % (9/175) of cases and no deaths were reported. Figure Incidence of yersiniosis: Ontario, Ontario Population: Population Estimates [ ], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

186 Figure Incidence of yersiniosis by age and sex: Ontario, 2013 Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Figure Number of yersiniosis cases by month: Ontario, Yr Average: Represents the five-year ( ) average of the number of cases reported in the corresponding month. Reportable Disease Trends in Ontario,

187 Map Incidence of yersiniosis by public health unit of residence: Ontario, 2013 PHU Cases (n) *Rates PHU Cases (n) *Rates PHU Cases (n) *Rates ALG KFL REN BRN LAM SMD CHK LGL SUD DUR MSL THB ELG NIA TOR EOH NPS TSK GBO NWR WAT HAL OTT WDG HAM OXF WEC HDN PDH YRK HKP PEE HPE PQP HUR PTC Ontario Ontario Population: Population Estimates [2013], Statistics Canada, distributed by MOHLTC, received [2014/07/03]. Reportable Disease Trends in Ontario,

188 References 7. Hale CR, Scallan E, Cronquist AB, Dunn J, Smith K, Robinson T, et al. Estimates of enteric illness attributable to contact with animals and their environments in the United States. Clin Infect Dis. 2012;54 Suppl 5:S Available from: df+html 8. Gilca R, Fortin E, Frenette C, Longtin Y, Gourdeau M. Seasonal variations in Clostridium difficile infections are associated with influenza and respiratory syncytial virus activity independently of antibiotic prescriptions: a time series analysis in Quebec, Canada. Antimicrob Agents Chemother. 2012;56(2): Available from: 9. Middleton D, Naus M. Cyclospora Surveillance in Ontario, PHERO. 2001;12(10): Middleton D, Naus M. Cyclospora Case Surveillance in Ontario, PHERO. 2000;11(10): Ontario Agency for Health Protection and Promotion (Public Health Ontario). Monthly infectious diseases surveillance report: June 2014 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2014 [cited 2015 Apr 20]. Available from: cuments/pho_monthly_infectious_diseases_surveillance_re port_-_june_2014.pdf 1. Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix B: Provincial case definitions for reportable diseases. Disease: Acquired Immunodeficiency Syndrome (AIDS). Revised December 2014 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2009 [cited 2015 Apr 20]. Available from: oph_standards/docs/aids_cd.pdf 2. Public Health Agency of Canada. Case definitions for communicable diseases under national surveillance. Can Commun Dis Rep. 2009;35S2: Available from: 3. Desai S, Smith T. Surveillance studies in 2013: Acute flaccid paralysis: January 1996 to December In: Canadian Paediatric Society; Public Health Agency of Canada. Canadian Paediatric Surveillance Program: 2013 results [Internet]. Ottawa, ON: Canadian Paediatric Society; 2014 [cited 2015 Apr 20]. Available from: pdf 4. Global Polio Eradication Initiative. Acute Flaccid Paralysis (AFP) surveillance [Internet]. Geneva: World Health Organization; 2010 [cited 2014 Oct 14]. Available from: ance.aspx 5. Canadian Food Inspection Agency. Fact sheet - Brucellosis [Internet]. Ottawa, ON: Government of Canada; 2011 [cited 2015 Apr 20]. Available from: 6. Strachan N, Watson R, Novik V, Hofreuter D, Ogden I, Galan J. Sexual dimorphism in campylobacteriosis. Epidemiol Infect. 2008;136(11): Available from: /S a.pdf 12. National Advisory Committee on Immunization; Public Health Agency of Canada. Canadian immunization guide [Internet]. Evergreen ed. Ottawa, ON: Hery Majesty the Queen in Right of Canada; 2012 [cited 2015 Apr 20]. Part 4: active vaccines: Diphtheria toxoid. Available from: Reportable Disease Trends in Ontario,

189 13. Ontario. Ministry of Health and Long-Term Care. Publicly funded immunization schedules for Ontario August 2011 [Internet]. Toronto, ON: Queen s Printer for Ontario; 2011 [cited 2013 Dec 31]. Available from: ion/docs/schedule.pdf 14. Vrbova L, Johnson K, Whitfield Y, Middleton D. A descriptive study of reportable gastrointestinal illnesses in Ontario, Canada, from 2007 to BMC Public Health. 2012;12(970). Available from: Ontario Agency for Health Protection and Promotion (Public Health Ontario). Monthly infectious diseases surveillance report: November 2012 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2012 [cited 2015 Apr 20]. Available from: cuments/2012_november_pho_monthly_report.pdf 16. Allen VG, Mitterni L, Seah C, Rebbapragada A, Martin IE, Lee C, et al. Neisseria gonorrhoeae treatment failure and susceptibility to cefixime in Toronto, Canada. JAMA. 2013;309(2): Ontario Agency for Health Protection and Promotion (Public Health Ontario). Guidelines for testing and treatment of gonorrhea in Ontario. Toronto, ON: Queen's Printer for Ontario; Available from: es_gonorrhea_ontario_2013.pdf 19. Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix B: Provincial case definitions for reportable diseases. Disease: Hepatitis B. Revised December 2014 [Internet]. Toronto, ON: Queen's Printer for Ontario; Available from: oph_standards/docs/hep_b_cd.pdf 20. Heymann DL, editor. Viral Hepatitis B. In: Control of communicable diseases manual. 19 th ed. Washington, DC: American Public Health Association; p Centers for Disease Control and Prevention. Hepatitis B FAQs for the Public [Internet]. Atlanta GA: Centers for Disease Control and Prevention; 2015; [cited 2015 Apr 20]. Available from: Kwong JC, Crowcroft NS, Campitelli MA, Ratnasingham S, Daneman N, Deeks SL, et al. Ontario Burden of Infectious Disease Study (ONBOIDS): an OAHPP/ICES Report. Toronto, ON: Ontario Agency for Health Protection and Promotion; Institute for Clinical Evaluative Sciences; Available from: ICES_Report_ma18.pdf 23. Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix B: Provincial case definitions for reportable diseases. Disease: Hepatitis C. Toronto, ON: Queen's Printer for Ontario; Available from: oph_standards/docs/hep_c_cd.pdf 18. Ontario Agency for Health Protection and Promotion (Public Health Ontario). Monthly infectious disease surveillance report: January 2013 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2013 [cited 2014 Jan 31]. Available from: cuments/2013_january_pho_monthly_report.pdf 24. Heymann DL, editor. Viral Hepatitis C. In: Control of communicable diseases manual. 19 th ed. Washington, D.C.: American Public Health Association; p Ontario Agency for Health Protection and Promotion (Public Health Ontario). Influenza and respiratory infection surveillance summary report: Season. Toronto, ON: Queen's Printer for Ontario; Available from: _Respiratory_Infection_Surveillance_Summary_Report_2012 _13.pdf Reportable Disease Trends in Ontario,

190 26. Ontario Agency for Health Protection and Promotion (Public Health Ontario). Public Health Ontario Laboratorybased respiratory pathogen surveillance report, Weeks (August 21 September 3, 2011) [Internet]. Toronto, ON: Queen's Printer of Ontario; 2011 [cited 2015 Apr 20]. Available from: cuments/pho%20%20laboratory- Based%20Respiratory%20Pathogen%20Surveillance%20Repo rt%20weeks% pdf 27. Ontario Agency for Health Protection and Promotion (Public Health Ontario). Ontario influenza bulletin : surveillance season (September 1, September 3, 2011) [Internet]. Toronto, ON: Queen's Printer Ontario; 2011 [cited 2015 Apr 20]. Available from: cuments/influenza%20bulletin-week% pdf 28. Ontario Agency for Health Protection and Promotion (Public Health Ontario). Ontario influenza bulletin : surveillance season (September 1, September 1, 2012) [Internet]. Toronto, ON: Queen's Printer for Ontario; 2012 [cited 2014 Jan 31]. Available from: cuments/influenza%20bulletin-weeks%2034_35.pdf 29. Skowronski DM, Janjua NZ, De Serres G, Sabaiduc S, Eshaghi A, Dickinson JA, et al. Low influenza vaccine effectiveness associated with mutation in the egg-adapted H3N2 vaccine strain not antigenic drift in circulating viruses. PLoS One. 2014;9(3):e Available from: one Adam HJ, Richardson SE, Jamieson FB, Rawte P, Low DE, Fisman DN. Changing epidemiology of invasive Haemophilus influenza in Ontario, Canada: Evidence for herd effects and strain replacement due to HiB vaccination. Vaccine. 2010;28: Greenberg DP, Doemland M, Bettinger JA, Scheifele DW, Halperin S. Epidemiology of pertussis and Haemophilus influenza type b disease in Canada with exclusive use of a diphtheria-tetanus-acellular pertussis-inactivated poliovirus- Haemohpilus influenza type b pediatric combination vaccine and an adolescent-adult tetanus-diphtheria-acellular pertussis vaccine. Pediatr Infect Dis J. 2009;28: Ontario Agency for Health Protection and Promotion (Public Health Ontario). Epidemiology of legionellosis in Ontario, Surveillance period: January 1, 2013 to December 31, Toronto, ON: Queen's Printer of Ontario; Available from: logy_legionellosis_ontario_report_2013.pdf 33. Public Health Agency of Canada. Enhanced listeriosis surveillance 2012 technical report. Ottawa, On: Her Majesty the Queen in Right of Canada; Nelder MP, Russell C, Lindsay LR, Dhar B, Patel SN, Johnson S, et al. Population-based passive tick surveillance and detection of expanding foci of blacklegged ticks Ixodes scapularis and the Lyme disease agent Borrelia burgdorferi in Ontario, Canada. PLoS One. 2014;9(8):e Available from: one Public Health Agency of Canada. Elimination of measles, rubella and congenital rubella syndrome in Canada: documentation and verification report: executive Summary [Internet]. Ottawa, ON: Her Majesty the Queen in Right of Canada; 2013 [2013 May 15]. Available from: Pan American Health Organization. Plan of action for the documentation and verification of measles, rubella, and congenital rubella syndrome elimination in the region of the Americas. Washington, D.C.: Pan American Health Organization; Available from: ask= doc_download&gid=16739&itemid=&lang=en Reportable Disease Trends in Ontario,

191 37. Shane A, Hiebert J, Sherrard L, Deehan H. Measles surveillance in Canada: trends for Can Commun Dis Rep. 2014; Available from: 12-surv-1-eng.php 38. Lim GH, Deeks SL, Fediurek J, Gubbay J, Crowcroft NS. Documenting the elimination of measles, rubella, and congenital rubella syndrome in Ontario: Can Commun Dis Rep. 2014;40-8. Available from: 39. Novartis Pharmaceuticals Canada. BEXSERO product monograph. Dorval, QC: Novartis Pharmaceuticals Canada; Available from: Jafri RZ, Ali A, Messonnier NE, Tevi-Benissan C, Durrheim D, Eskola J, et al. Global epidemiology of invasive meningococcal disease. Popul Health Metr. 2013;11(1):17. Available from: Public Health Agency of Canada. Guidelines for the prevention and control of mumps outbreaks in Canada. Can Commun Dis Rep. 2010;36 Suppl 1:1-46. Available from: aspc.gc.ca/publicat/ccdr-rmtc/14vol40/dr-rm40-12/dr-rm Deeks SL, Lim GH, Simpson MA, Gagne L, Gubbay J, Kristjanson E, et al. An assessment of mumps vaccine effectiveness by dose during an outbreak in Canada. CMAJ. 2011;183(9): Available from: Ontario. Ministry of Health and Long-Term Care. Ontario annual infectious diseases epidemiology report, 2009 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2011 [cited 2015 Apr 20]. Available from: ons/reports/epi_reports/epi_report_2009.pdf 44. Wielders CC, van Binnendijk RS, Snijders BE, Tipples GA, Cremer J, Fanoy E, et al. Mumps epidemic in orthodox religious low-vaccination communities in the Netherlands and Canada, 2007 to Euro Surveill. 2011;16(41): Available from: Centres for Disease Control and Prevention. Mumps outbreak-new York, New Jersey, Quebec, Morb Mortal Wkly Rep. 2009;58: Available from: htm 46. Stein-Zamir C, Shoob H, Abramson N, Tallen-Gozani E, Sokolov I, Zentner G. Mumps outbreak in Jerusalem affecting mainly male adolescents. Euro Surveill. 2009;14(50):pii: Available from: Heymann DL, editor. Paratyphoid fever. In: Control of Communicable Diseases Manual. 19 th ed. Washington, D.C.: American Public Health Association; p Lim GH, Deeks SL, Crowcroft NS. A cocoon immunisation strategy against pertussis for infants: does it make sense for Ontario? Euro Surveill. 2014;19(5):pii: Available from: World Health Organization. Immunization, vaccines and biologicals: Pertussis [Internet]. Geneva: World Health Organization; 2011 [cited 2015 Apr 20]. Available from: Smith T, Rotondo J, Desai S, Deehan H. Pertussis surveillance in Canada: trends to Can Commun Dis Rep. 2014;40(3). Available from: aspc.gc.ca/publicat/ccdr-rmtc/14vol40/dr-rm40-03/dr-rm40-03-per-eng.php Reportable Disease Trends in Ontario,

192 51. Deeks S, Lim G, Walton R, Fediurek J, Walker C, Walters J, et al. Prolonged pertussis outbreak in Ontario originating in an under-immunized religious community. Can Commun Dis Rep. 2014;40(3). Available from: aspc.gc.ca/publicat/ccdr-rmtc/14vol40/dr-rm40-03/dr-rm40-03-ont-eng.php 52. Lim GH, Wormsbecker A, McGeer AM, Pillai DR, Gubbay J, Rudnick W, et al. Have changing pneumococcal vaccination programmes impacted disease in Ontario? Vaccine. 2013;31(24): Kuster SP, Tuite AR, Kwong JC, McGeer A, Toronto Invasive Bacterial Diseases Network, et al. Evaluation of coseasonality of influenza and invasive pneumococcal disease: results from prospective surveillance. PloS Med. 2011;8(6):e Available from: rnal.pmed Helferty M, Rotondo J, Martin I, Desai S. The epidemiology of invasive pneumococcal disease in the Canadian North from 1999 to Int J Circumpolar Health. 2013;72. Available from: cle/view/ National Advisory Committee on Immunization; Public Health Agency of Canada. Canadian immunization guide [Internet]. Evergreen ed. Ottawa, ON: Her Majesty the Queen in Right of Canada; 2012 [cited 2013 Dec 31]. Part 4: active vaccines: poliomyelitis vaccine. Available from: Global Polio Eradication Initiative. Polio this week as of 15 Apr 2015 [Internet]. Geneva: World Health Organization; 2010 [cited 2015 Apr 20]. Available from: oliothisweek.aspx 57. National Advisory Committee on Immunization; Public Health Agency of Canada. Canadian immunization guide [Internet]. Evergreen ed. Ottawa, ON: Her Majesty the Queen in Right of Canada; 2012 [cited 2013 Feb 22]. Part 4: active vaccines: Rubella vaccine. Avaialble from: Public Health Agency of Canada. Fact sheet: shigellosis [Internet]. Ottawa, ON: Government of Canada; 2013 [cited 2015 Apr 20]. Available from: Trepanier S, Bui YG, Blackburn M, Milord F, Levac E, Gagnon S. Travel-related shigellosis in Quebec, Canada: an analysis of risk factors. J Travel Med. 2014;21(5): World Health Organization. The Smallpox Eradication Programme - SEP ( ) [Internet]. Geneva: World Health Organization; 2015 [cited 2015 Feb 24]. Available from: Public Health Agency of Canada. Smallpox [Internet]. Ottawa, ON: Government of Canada; 2004 [cited 2013 Feb 8]. Available from: Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix A: Diseasespecific chapters. Chapter: Smallpox. Toronto, ON: Queen's Printer for Ontario; Available from: oph_standards/docs/smallpox_chapter.pdf 63. Leber A, MacPherson P, Lee BC. Epidemiology of infectious syphilis in Ottawa. Recurring themes revisited. Can J Public Health. 2008;99(5): Ontario Agency for Health Protection and Promotion (Public Health Ontario). Monthly infectious disease surveillance report: June 2013 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2013 [cited 2015 Apr 20]. Available from: cuments/pho_monthly_infectious_diseases_surveillance_re port_-_june_2013.pdf 65. Toronto Public Health. Ongoing syphilis outbreak in Toronto [Internet]. Toronto, ON: Toronto Public Health; 2014 [cited 2014 Sep 26]. Available from: 7db12f763c322410VgnVCM d60f89RCRD Reportable Disease Trends in Ontario,

193 66. Public Health Agency of Canada. Canadian guidelines on sexually transmitted infections [Internet]. Ottawa, ON: Her Majesty the Queen in Right of Canada; 2010 [cited 2014 Jan 31]. Available from: Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix B: provincial case definitions for reportable diseases. Disease: Syphilis. Revised December 2014 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2014 [cited 2015 Apr 20]. Available from: oph_standards/docs/syphilis_cd.pdf 68. National Advisory Committee on Immunization; Public Health Agency of Canada. Canadian immunization guide [Internet]. Evergreen ed. Ottawa, ON; Her Majesty the Queen in Right of Canada; 2012 [cited 2014 Jan 1]. Part 4: active vaccines: Tetanus toxoid. Available from: Public Health Agency of Canada. Variant Creutzfeldt-Jakob disease in a Canadian resident. Can Commun Dis Rep Available from: Public Health Agency of Canada. Creutzfeldt-Jakob disease, classic and variant: nationally notifiable since Can Commun Dis Rep. 2009;35S2: Available from: Ontario. Ministry of Health and Long-Term Care. Infectious diseases protocol, Appendix B: Provincial case definitions for reportable diseases. Disease: Transmissible Spongiform Encephalopathy, including: Creutzfeldt-Jakob Disease, all types; ii) Gerstmann- SträusslerScheinker Syndrome; iii) Fatal Familial Insomnia, and iv) Kuru. Toronto, ON: Queen's Printer for Ontario; Available from: oph_standards/docs/tse_cd.pdf 73. World Health Organization. Global tuberculosis report Geneva: World Health Organization; Available from: _eng.pdf?ua=1 74. Ontario Agency for Health Protection and Promotion (Public Health Ontario). Monthly infectious disease surveillance report: March Toronto ON: Queen's Printer for Ontario; Available from: cuments/pho_monthly_infectious_diseases_surveillance_re port_-_march_2014.pdf 75. Public Health Agency of Canada. Canadian tuberculosis standards. 7th ed. Ottawa, ON: Her Majesty the Queen in Right of Canada, as represented by the Minister of Health; 2014 [cited 2015 Apr 20]. Available from: TB_Standards_7th_Edition_ENG.pdf 71. American Academy of Pediatrics. Transmissible spongiform encephalopathies. In: Pickering LK, Baker CJ, Kimberlin DW, Long SS, editors. Red book: 2012 report of the Committee on Infectious Diseases. 29 th ed. Elk Grove Villgae, IL: American Academy of Pediatrics; p Health Canada. Epidemiology of tuberculosis in First Nations living on-reserve in Canada, Ottawa, ON: Health Canada; Public Health Agency of Canada. Statement on measlesmumps-rubella-varicella vaccine (ACS-9). Can Commun Dis Rep. 2010;36(ACS-9):1-22. Available from: Reportable Disease Trends in Ontario,

194 78. Ontario. Ministry of Health and Long-Term Care. Infectious diseases protocol, Appendix B: Provincial case definitions for reportable diseases. Disease: Varicella (chickenpox). Revised January 2014 [Internet]. Toronto, ON: Queen s Printer for Ontario; 2014 [cited 2014 Jan 10]. Available from: oph_standards/docs/chickenpox_cd.pdf 79. Ontario. Ministry of Health and Long-Term Care. Infectious diseases protocol, Appendix A: Diseasespecific chapters. Disease: Varicella (chickenpox). Revised January 2014 [Internet]. Toronto, ON: Queen s Printer for Ontario; 2014 [cited 2014 Jan 10]. Available from: oph_standards/docs/chickenpox_chapter.pdf 80. Ontario. Ministry of Health and Long-Term Care. iphis bulletin #10. Toronto, ON: Queen's Printer for Ontario; Ontario. Ministry of Health and Long-Term Care. iphis Bulletin #13. Revised November Toronto, ON: Queen's Printer for Ontario; Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix A: Diseasespecific chapters. Chapter: Measles. Revised August 2014 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2014 [cited 2014 Apr 3]. Available from: oph_standards/docs/measles_chapter.pdf 87. Ontario. Ministry of Health and Long-Term Care. Infectious Diseases Protocol, Appendix A: Diseasespecific chapters. Chapter: Rubella. Revised January 2013 [Internet]. Toronto, ON: Queen's Printer for Ontario; 2013 [cited 03 April 2014]. Available from: oph_standards/docs/rubella_chapter.pdf 81. Ontario. Ministry of Health and Long-Term Care. iphis final outbreak summary user guide v5 ( ). Toronto, ON: Queen's Printer for Ontario; Tataryn J, Morton V, Cutler J, McDonald L, Whitfield Y, Billard B, et al. Outbreak of E. coli O157:H7 associated with lettuce served at fast food chains in the Maritimes and Ontario, Canada, Dec Can Commun Dis Rep. 2014;40(S1). Available from: aspc.gc.ca/publicat/ccdr-rmtc/14vol40/dr-rm40s-1/dr-rm40s- 1-ecoli-eng.php 83. Canadian Food Inspection Agency. Updated health hazard alert - certain uncooked lean ground beef may contain E. coli O157:H7 bacteria [Internet]. Ottawa, ON: Government of Canada; 2013 [cited 2015 Apr 20]. Available from: recall-warnings/complete-listing/ /eng/ / Thomas MK, Majowicz SE, Sockett PN, Fazil A, Pollari F, Dore K, et al. Estimated numbers of community cases of illness due to Salmonella, Campylobacter and verotoxigenic Escherichia Coli: Pathogen-specific community rates. Can J Infect Dis Med Microbiol. 2006;17(4): Available from: Thomas MK, Majowicz SE, Pollari F, Sockett PN. Burden of acute gastrointestinal illness in Canada, : interim summary of NSAGI activities. Can Commun Dis Rep. 2008;34(5):8-15. Available from: Heymann DL, editor. Yersiniosis. In: Control of communicable diseases manual. 19 th ed. Washington, D.C.: American Public Health Association; p Reportable Disease Trends in Ontario,

195 Appendices Reportable Disease Trends in Ontario,

196 Appendix 1 Technical notes Data sources Ontario reportable disease data The main source for reportable diseases data (case counts and calculated incidence rates) in this report is the integrated Public Health Information System (iphis), the electronic reporting system for reportable diseases in Ontario. iphis replaced the Reportable Diseases Information System (RDIS) and was implemented in phases throughout 2005 starting on April 1, with full implementation by all 36 local public health units (PHUs) by the end of that year. In Ontario, over 70 diseases have been specified as reportable under Regulation 559/91 pursuant to the Health Protection and Promotion Act (HPPA), R.S.O Public Health Ontario (PHO) is aware of cases and related data elements reported by the local PHUs in accordance with the HPPA, Ontario Regulation 569, the Ontario Public Health Standards, and the Infectious Diseases Protocol. Laboratory confirmation of reportable disease cases most frequently occurs at public health laboratories operated by PHO. For some diseases, laboratory confirmation can take place at hospitals or private laboratories as well. In other instances, reference services and specialized testing of clinical specimens takes place at reference laboratories across Canada. The iphis data used in this report were extracted between May 14, 2014, and January 13, The exception is for historical counts of three influenza seasons. For the , , and seasons, data were extracted from iphis on November 13, For the and seasons, during which the influenza A(H1N1)pdm09 pandemic took place, aggregate reporting was used to report many influenza A(H1N1)pdm09 cases; these historical counts were compiled based on data extracted on September 3, 2009, September 9, 2010, and August 10, 2011, and represent a combination of aggregate and case-level data for all influenza types. For selected diseases, additional data sources were used to supplement iphis data to increase either completeness of case ascertainment or data quality: For invasive Haemophilus influenzae type B disease (Hib) and invasive meningococcal disease (IMD), iphis data were linked to Public Health Ontario Laboratories (PHOL) data to identify additional confirmed cases of disease and to help to rule out cases that were incorrectly classified. Due to some degree of under-reporting in iphis, and the use of additional data from PHOL, the case counts presented during these years may not be consistent with case counts derived solely using iphis data. Further information regarding linkage is included in the disease-specific chapters for Hib and IMD. For influenza and legionellosis, PHOL per cent positivity data were extracted from the Laboratory Information Management System (LIMS) on March 26, 2014 and August 26, 2014, respectively. For chlamydia and gonorrhea, per cent positivity data were downloaded from STI Online on November 14, 2014, based on data extracted from LIMS on October 31, For varicella, in addition to the data that were extracted from iphis, RDIS data were downloaded from the ehealth Ontario Portal on May 24, 2012 (see below for additional information on varicella under the section Descriptive Measures: Case counts: Varicella ). Reportable Disease Trends in Ontario,

197 Population and live birth data IntelliHEALTH Ontario is a repository of health-related data that describes the population and delivery of health care services in Ontario. Population and live birth counts for Ontario are originally sourced from Statistics Canada, and were obtained either from the Ontario Ministry of Health and Long-Term Care (MOHLTC) or through IntelliHEALTH Ontario. General population estimates were received from MOHLTC on July 3, Live birth data were extracted by PHO from IntelliHEALTH Ontario on November 29, These two sources of population data were used as denominators to calculate overall, age-, sex- and PHUspecific crude incidence rates, where applicable. National comparator data Comparator incidence rates for Canada are provided in the report whenever available. These data were obtained directly from the Public Health Agency of Canada (PHAC) on July 15, For most diseases in this report, comparator incidence rates for Canada are used for the years in trend over time graphs. Depending on the disease and when it became nationally notifiable, national incidence rates may not be available for all or part of this period. As a result, comparisons between trends in provincial and national incidence rates are made only for years for which national incidence rates are provided. National rates are also not provided for diseases where the data provided do not distinguish between different forms of the disease, such as syphilis (i.e., infectious and noninfectious) and hepatitis B (i.e., acute and chronic). Incidence rates for Canada presented in this report may differ from reports published by PHAC. Where such discrepancies exist, incidence rates published in more recent national reports supersede those in this report. A list of diseases that are nationally notifiable can be found on PHAC s website. available online in Appendix B of the Infectious Diseases Protocol. Please note that some of the definitions currently available online no longer reflect the case definitions that were in effect during Changes to provincial surveillance case definitions and disease classifications have occurred over the years to reflect the changing epidemiology of infectious diseases and the use of more current laboratory diagnostic practices and technology. Cases are classified in iphis according to the MOHLTC surveillance case definitions used at the time the case was identified. PHUs are responsible for ensuring that cases reported to the province meet the relevant case definition. Consideration of changes to provincial case definitions and associated case classifications over time are important when interpreting the disease trends presented in this report. Case classifications Unless otherwise stated, case counts include only the confirmed case classification. Probable cases are included in the total counts presented in this report for Lyme disease, mumps, pertussis, amebiasis, IMD, and West Nile Virus (WNV) illness. Following case definition changes in 2009, cases that previously met the confirmed case definition were subsequently required to be reported as probable for certain diseases: For Lyme disease, mumps, and pertussis, the impact of this change was substantial, such that probable cases since 2009 constituted a significant proportion of total case counts. As a result, probable case counts are included in total counts (since January 1, 2009 for Lyme disease, and since April 28, 2009 for mumps and pertussis) in order to ensure valid comparisons over time for these diseases. Case definitions Appendix 2 lists the reportable diseases and associated case classifications that were reportable in Ontario for The most recent provincial case definitions are Probable cases since January 1, 2009 are included in counts for amebiasis owing to the change in interpretation of laboratory test results that previously reported the causative agent as E. histolytica/e. dispar with no Reportable Disease Trends in Ontario,

198 distinction between the two. Cases with test results that do not differentiate between the non-pathogenic E. dispar and the pathogenic E. histolytica are now counted as probable, whereas they were previously counted as confirmed. The impact of this change was significant, and as a result, probable case counts since 2009 are included in total counts to ensure valid comparisons over time for amebiasis. Probable cases since April 28, 2009 are included in counts for IMD to ensure comparability for assessing trends over time, since cases currently classified as probable would have been classified as confirmed prior to the case definition change in For the vast majority of diseases similarly impacted by the 2009 case definition changes, the impact on overall counts was negligible and, as such, probable cases for these diseases are not included in this report. For measles, rubella and congenital rubella syndrome (CRS), probable cases are excluded from the historical temporal trend despite being reportable at the provincial level, since they have been eliminated from Canada and strict criteria are required to identify cases; no probable cases were reported in For hepatitis B, confirmed acute cases are captured with the Classification Description of CONFIRMED in iphis. The confirmed chronic hepatitis B cases described in this report are those reported in iphis with the CARRIER Classification Description. When a case progresses from acute to chronic infection, PHUs create a chronic CARRIER case, in addition to the existing acute CONFIRMED case. Therefore, counts of acute and chronic hepatitis B cases are not mutually exclusive and should not be summed as this would result in double-counting of cases. Both AIDS and HIV cases are captured under the Disease field HIV/AIDS in iphis. HIV cases may have the Encounter Type of CARRIER and the Diagnosis Status of CARRIER. If cases progress from HIV infection to AIDS, PHUs update the Encounter Type to CASE and the Diagnosis Status to CONFIRMED. Therefore, counts of AIDS and HIV cases are not mutually exclusive and should not be summed as this would result in double-counting of cases. Both HIV and AIDS cases may have the Encounter Type of CASE and Diagnosis Status of CONFIRMED in iphis; where HIV cases are counted based on the Encounter Date and AIDS cases are counted based on the Diagnosis Status Date. Descriptive measures The descriptive measures used throughout the report to characterize the epidemiology of reportable infectious diseases in Ontario are listed below. Case counts This measure refers to the total number of reported cases of a disease in a calendar year and within a select group or sub-group that were reported as confirmed and/or probable, as applicable. For tuberculosis (TB), only active cases are included in the reporting of confirmed cases (i.e., latent TB infections are not included), and for syphilis, only infectious cases (i.e., primary, secondary, early latent, and infectious neurosyphilis) and congenital cases are included in the reporting of confirmed cases. For influenza, cases are counted in the influenza season within which they occurred, rather than by calendar year. Influenza seasons run from September 1 of one year to August 31 of the following year. For example, the influenza season started on September 1, 2012 and ended on August 31, Varicella For varicella, cases are reported provincially as both individual and aggregate cases. Additional information on determining case counts for varicella is available in the disease-specific chapter. Clostridium difficile infection (CDI) outbreaks and cases Details on determining counts for CDI outbreaks and cases are available in the disease-specific chapter. Reportable Disease Trends in Ontario,

199 Crude incidence rates (generally reported as rates per 100,000 population per year) Crude incidence rates are calculated by dividing the total case count in a year by the total number of people at risk of acquiring the disease in that year. As specified in the Case Classifications section above, the total case count for some diseases may include confirmed and probable cases. In this report, most rates are presented per 100,000 population, unless otherwise specified. For instance, diseases where counts are too small for rates per 100,000 to be informative (e.g., if many of the incidence rates presented in a chapter are less than 0.1 cases per 100,000 population) may have rates presented per 1,000,000 population instead. The formulas for calculating overall and population-specific rates used throughout the report are noted below (using the example of rates presented in a specified time period per 100,000 population). Number of cases in specified time period and population Total number of people in that population 100,000 Overall: Number of all new cases in a specified time period divided by the Ontario population for that time period, multiplied by 100,000. Group-specific: Number of new cases in a subgroup (e.g., age group, sex, or PHU) in a specified time period divided by the Ontario population for that sub-group for that time period, multiplied by 100,000. Neonatal: Number of new congenital or neonatal cases of a disease (cases occurring up to 28 days old) in a specified time period divided by the total number of live births for that time period, multiplied by 100,000. Live births are used as the denominator to calculate incidence rates for neonatal diseases because the neonatal population count (up to 28 days old) could not be determined from available vital statistics data. In general, incidence rate is defined as the number of new cases of disease occurring in a specified period. Throughout the report, the term incidence rate refers to an annual rate (e.g., the number of cases observed for every 100,000 Ontarians per year), unless otherwise specified. Cases are attributed to a particular year based on their Episode date, as outlined in the section Data Management: Reference Period below. There are some exceptions to reporting of incident cases; for example, HIV, chronic hepatitis B, hepatitis C, tuberculosis, late latent syphilis, and neurosyphilis are often undiagnosed for extended periods, and their detection by public health is generally not indicative of the actual time the infection was acquired. Therefore in some instances, cases included in this report for a particular year are individuals who acquired their infections in earlier years, and the data represent new diagnosis rates rather than rates of new infection. Public health unit distribution Unless otherwise specified, this measure refers to the number of new cases reported by each PHU in 2013 (or a multi-year time period, where indicated). Crude incidence rates are also provided for each PHU, and are calculated as per the group-specific incidence rate formula described above. Orientation of case counts by PHU is based on the Diagnosing Health Unit (DHU), which refers to the case's health unit of residence at the time of illness onset, and does not necessarily reflect the location of exposure or diagnosis. iphis Bulletin #13 provides additional detail on scenarios in which a health unit is considered the DHU. 85 Cases for which the DHU was reported as MOHLTC (to signify a case that is not a resident of Ontario) or Muskoka Parry Sound (a health unit that no longer exists) have been excluded. Incidence rates by PHU are presented in both tables and maps where a disease has sufficiently high enough counts to do so. In the maps, incidence rates are grouped into four categories; a fifth category representing zero incidence is included for some diseases (e.g., eliminated diseases, measles and rubella; non-endemic diseases such as malaria; and diseases with relatively lower counts where a map is provided, such as listeriosis). Generally, the categories for each disease are defined by splitting the range between zero and the highest PHU incidence rate into equal intervals. Where a disease has consistently high PHU incidence Reportable Disease Trends in Ontario,

200 rates, such that the inclusion of zero in the range to define categories would affect the ability to illustrate meaningful variations between PHUs, the range may be defined based on the lowest and highest PHU incidence rates. Age distribution Age groups for most diseases are based on standard five- and 10-year age groupings. For vaccinepreventable diseases, age groups are constructed with consideration of the epidemiology of the disease, the vaccination program, and in some cases, the birth cohort(s) and implementation year of Ontario publicly funded immunization programs. Monthly incidence For selected diseases, the number of cases that occurred during each month in 2013 is compared to monthly averages for the previous five years/seasons. For influenza, the five-year monthly averages for comparison include only the non-pandemic seasons from to The influenza A(H1N1)pdm09 pandemic occurred during the and seasons, resulting in influenza counts that were significantly higher than non-pandemic seasons. Exclusion of these seasons allows for the determination of baseline monthly averages that are more in line with expected trends for non-pandemic seasons. For CDI, the number of outbreaks each month is compared to the monthly average for the previous four years. Immunization status For vaccine-preventable diseases, immunization status is determined through an assessment of immunization administration dates that were entered in iphis. In the absence of any immunization dates, cases with an affirmative response to being unimmunized as a risk factor are classified as unimmunized. In the event no administration dates and risk factors were entered, the case is determined to have an unknown immunization status. The number of valid doses takes into consideration the related vaccination agent, appropriate interval between the most recent dose and onset of illness, and age at immunization, which varies among diseases. Hospitalization This measure refers to the proportion of cases that were reported as hospitalized. In this report, a case is considered hospitalized if at least one hospital admission date was recorded for the case of interest. It should be noted that under-reporting of hospitalizations may occur in iphis, as hospitalizations and admission dates may not always be reported to PHUs. Deaths The case fatality ratio refers to the proportion of cases that were reported as fatal within a specified period. For most diseases described in this report, a case is counted as having died where an Outcome of FATAL is reported at the case level, except when the only type/cause of death (Type of Death for Outbreak module, Cause of Death for the STD module) entered in the iphis case record is REPORTABLE DISEASE WAS UNRELATED TO CAUSE OF DEATH. For tuberculosis, any case with a Date of Death entered in iphis was counted as fatal, except when the only cause of death entered in the iphis case record is REPORTABLE DISEASE WAS UNRELATED TO CAUSE OF DEATH. The criteria for TB are different than for most other diseases because the TB module is set up differently in iphis, and the general criteria could not be applied. It should be noted that there may be variability among PHUs in terms of followup of cases to determine outcomes as well as how the deaths are categorized in the type/cause of death fields. Cases from 2013 for whom treatment is ongoing, or the disease is chronic, may become fatal at a point in time after the extraction of data; these deaths would not be reflected in this report. Case fatality data for hepatitis B, hepatitis C, HIV/AIDS, and TB are likely to be particularly impacted by this issue. For CDI cases, any outbreak-linked confirmed cases that were reported with an outcome of fatal, or that had a date of death entered during the outbreak period, are counted as a fatal case; however, deaths reported are all-cause related and may or may not be attributable to CDI directly. Reportable Disease Trends in Ontario,

201 Subtype/serotype/serogroup/genotype The number and proportion of cases that represent distinct variations of a specific species, subtype, serotype, serogroup, or genotype of a pathogen that causes a reportable disease are provided for select diseases. Risk factors For CDI, the number and proportion of cases that reported each behavioural and medical risk factor are provided. Analysis software Data analysis and presentation for this report were completed using SAS version 9.3, and Microsoft Excel 2010 with the PowerPivot add-on. Identified differences in rates and counts from one period to another, between Ontario and Canada, and between population sub-groups are absolute and do not imply statistical significance. Data management Reference period The majority of information in this report reflects the number of incident cases reported in Ontario through iphis with Episode Dates from January 1 to December 31, Unless otherwise specified, historical data cover the period from 2004 to Passive surveillance systems such as iphis generally accommodate the entry of several dates to estimate the symptom onset date when it is not available. In Ontario, cases of most reportable diseases are classified by time using the Episode Date, which is an estimate of the symptom onset date of disease. In order to determine the Episode Date, the following hierarchy is in place in iphis: 1. Symptom Onset Date 2. Specimen Collection Date 3. Lab Test Date (date laboratory testing was performed) 4. Reported Date (date the case was reported to the PHU). During data extraction, the earliest date available at each stage in the hierarchy was selected as the Episode Date for each case. For example, if an onset date had been entered, it was selected as the Episode Date instead of the Specimen Collection Date, and so on. In some situations, the Episode Dates captured can be much later than the date of symptom onset (e.g., when the only date available is the reported date). Two reportable diseases are not classified by time based on the Episode Date: AIDS/HIV and TB. For HIV, incident case counts are based on the Encounter Date, defined as the date a case became known to public health. AIDS and TB incident case counts are based on the Diagnosis Status Date and Diagnosis Date, which is the date of a case s diagnosis for AIDS and TB, respectively. Case ascertainment criteria This report includes all confirmed (and probable, as applicable) reports of reportable diseases made through iphis with an Episode Date in 2013, with the following exclusions: 1. Cases who were not residents of Ontario at the time of diagnosis 2. Cases reported with a Disposition Status of ENTERED IN ERROR, DOES NOT MEET DEFINITION, DUPLICATE-DO NOT USE, or any variation on these values 3. Events reported as adverse events following immunization (AEFIs) and related data, which are published in a separate vaccine safety report 4. Cases reported as encephalitis, meningitis, or food poisoning 5. Institutional outbreaks of gastroenteritis (where the Aetiologic Agent was not CLOSTRIDIUM DIFFICILE ) and respiratory illness 6. Severe acute respiratory syndrome (SARS). 7. Cases with a missing outbreak number in iphis (i.e., sporadic cases should also have a sporadic outbreak number assigned in iphis). Appendix 2 provides a list of all reportable diseases in Ontario for 2013, and notes the reportable diseases that are excluded from this report. Reportable Disease Trends in Ontario,

202 Re-infections and co-infections For the majority of reportable diseases, immunity is not conferred following infection or wanes over time, resulting in continued susceptibility and potential for reinfection. It is assumed that cases representing reinfection, as opposed to relapse, were assessed by PHUs before entry into iphis based on several factors, including the incubation period for the disease in question. As a result, data in this report are assumed to be representations of true re-infections or new episodes of a disease. Thus a single person with more than one episode of the same disease in a single year may contribute more than one case of particular disease to the total provincial count for that year; for example, this may occur for individuals with chlamydia, gonorrhea, or salmonellosis. Co-infections with more than one infectious agent at the same time (e.g., Mycobacterium tuberculosis complex and HIV) or with different strains of an infectious agent (e.g., Salmonella Typhimurium and Salmonella Hadar) are reported as separate episodes of the resulting infections. Exposure determination Vaccine-preventable diseases For measles, rubella, and CRS, importation status is determined through a review of information entered in the exposures, risk factors, case notes, and comments fields in iphis. Imported or import-related case This definition applies to cases of measles, rubella and CRS. An imported case of measles or rubella is a case who travelled outside Canada 7 21 and days prior to symptom onset for measles and rubella, respectively. These definitions were modified from those provided by the Pan American Health Organization (PAHO) to reference travel outside Canada rather than the Americas, and to be consistent with the incubation periods specified in the Infectious Diseases Protocol, Appendix A (Measles, April 2014; Rubella, January 2013). 86,87 An import-related case is one that resulted from transmission by an imported case (i.e., epidemiologically-linked). For CRS, an imported case is one whose mother was outside Canada during the period when she may have had exposure to rubella that affected her pregnancy (from 23 days prior to conception or until week 24 of gestation). 38 Data limitations Accuracy of data PHO provides PHUs with preliminary case counts for the previous year in February or March for review and cleaning. These data are subsequently re-extracted in May/June and reported to PHAC as Ontario s case counts for the previous year. However, iphis is a dynamic disease reporting system which allows ongoing updates to data previously entered. As a result, any data extracted from iphis, including the data used in this report, represent a snapshot at the time of extraction and may differ from previous or subsequent reports. Discrepancies in disease counts and rates provided in this report and other published data may exist due to: Enhanced data cleaning for this report for select analyses, such as the linkage of iphis and laboratory data and subsequent reconciliation in iphis Late reporting Local and/or provincial-led data cleaning initiatives Differences in data extraction dates. Where such variability exists, data provided in other versions of this report, other PHO surveillance products (e.g., Monthly Infectious Diseases Surveillance Report), or published research may be more appropriate sources, depending on how the methodology, data caveats, and/or extraction dates align with the intended use of the data. Small counts For some diseases, the observed variability in population-specific incidence rates should be interpreted with caution owing to small counts, which may be exacerbated by small denominators (population). For this reason, population-specific rates are not routinely presented for diseases with small overall counts. Instead, counts over time may be combined into larger totals to provide more stable point Reportable Disease Trends in Ontario,

203 estimates of burden (e.g., total case count over 10 years). Under-reporting Passive surveillance systems such as iphis that primarily rely on mandatory physician and laboratory reports of illness can be characterized by under-reporting of the true burden of illness. As a result, case counts only represent known cases reported to PHUs and recorded in iphis. The resulting degree of under-reporting may vary from disease to disease due to a variety of factors such as disease awareness, medical care seeking behaviours, availability of health care, methods of laboratory testing, reporting behaviours, clinical practice, and severity of illness. 88,89 However, the extent of under-reporting for individual reportable diseases has not been fully assessed in Ontario. 1. Reporting the number or proportion of cases with missing data to provide perspective (e.g., age, sex) 2. Suppressing the data altogether 3. Excluding missing counts from the denominator when determining proportions 4. Merging data from multiple data sets or fields to create more complete data. Cases may also not be diagnosed or reported to PHUs, or may be reported but not entered into iphis. While these processes result in under-reporting, they are not accounted for in the analyses completed for this report. Duplicates The possibility of duplicates exists because duplicate sets are not identified and excluded unless they were resolved prior to data extraction either at the local or provincial level. Missing data (data not reported by PHUs) Data quality (completeness) for some fields is lower than others. Hospitalization and death are underreported in iphis, with the degree of under-reporting influenced by the severity of illness and associated outcomes (e.g., less under-reporting if illness or outcomes are more severe), and the timing of the event (i.e., there is likely less under-reporting if hospitalization or deaths occur shortly after symptom onset, or before case investigations are complete). Under-reporting of risk factors, immunization status, and specific laboratory data items (e.g., serotype, genotype) also occurs frequently. In general, the degree of underreporting is influenced by a combination of factors, including incomplete follow-up of cases (e.g., case is not reachable), incomplete or late entry of data in iphis, and the occurrence of deaths after follow-up has been completed. A high proportion of missing or incomplete data may result in conclusions or interpretations that are not representative of all cases. In this report, missing data may be handled in one of four ways: Reportable Disease Trends in Ontario,

204 Appendix 2 Reportable diseases and reportable classifications: Ontario, 2013 Reportable Diseases as specified under Ontario Regulation 559/91 and amendments under the Health Protection and Promotion Act. Reportable Disease Reportable Case Classifications Confirmed Probable Suspect Acquired immunodeficiency syndrome (HIV/AIDS) Acute Flaccid Paralysis (AFP) 6 Adverse events following immunization (AEFIs) 2 Amebiasis 1,7 Anthrax Botulism Brucellosis Campylobacter enteritis Chancroid Chickenpox (Varicella) Chlamydia trachomatis infections Cholera Clostridium difficile Infection (CDI) Outbreaks in Public Hospitals Cryptosporidiosis Cyclosporiasis Cytomegalovirus infection, congenital 3 Diphtheria Encephalitis 2 Primary, viral Post-infectious Vaccine-related Subacute sclerosing panencephalitis Unspecified Food poisoning, all causes 2 Gastroenteritis, institutional outbreaks 4 N/A N/A N/A Giardiasis, except asymptomatic cases Gonorrhea Group A Streptococcal disease, invasive Group B Streptococcal disease, neonatal Haemophilus influenzae b disease, invasive Hantavirus pulmonary syndrome Hemorrhagic fevers, including: Ebola virus disease Marburg virus disease Other viral causes Reportable Disease Trends in Ontario,

205 Reportable Disease Reportable Case Classifications Confirmed Probable Suspect Hepatitis A Hepatitis B 5 Hepatitis C Hepatitis D (Delta hepatitis) 3 Herpes, neonatal 3 Influenza Lassa fever Legionellosis Leprosy Listeriosis Lyme disease 1,7 Malaria Measles Meningitis, acute 2 Bacterial Viral Other Meningococcal disease, invasive 7 Mumps 1,7 Ophthalmia neonatorum Paralytic Shellfish Poisoning (PSP) 6 Paratyphoid fever Pertussis (whooping cough) 1,7 Plague Pneumococcal disease, invasive Poliomyelitis, acute Psittacosis/Ornithosis Q-fever Rabies Respiratory infection outbreaks in institutions 2 N/A N/A N/A Rubella Rubella, congenital syndrome 8 Salmonellosis Severe acute respiratory syndrome (SARS) 2 Shigellosis Smallpox Syphilis, infectious Tetanus Transmissible spongiform encephalopathy, including: Creutzfeldt-Jakob disease, all types Gerstmann-Sträussler-Scheinker syndrome 3 Fatal Familial Insomnia 3 Kuru 3 Reportable Disease Trends in Ontario,

206 Reportable Disease Reportable Case Classifications Confirmed Probable Suspect Trichinosis Tuberculosis Tularemia Typhoid fever Verotoxin-producing E. coli infection indicator conditions, including Haemolytic Uremic Syndrome West Nile Virus illness 1,7 Yellow Fever Yersiniosis Source: MOHLTC. Infectious Diseases Protocol, Appendix B: Provincial Case Definitions. Reportable classifications; Non-reportable classifications. 1: Routine reporting of case counts at the provincial level includes both confirmed and probable cases; confirmed cases only are for the other reportable diseases. 2: Reportable diseases not included in this report. 3: Note that these diseases were removed from the Ontario Reportable Disease List on December 4, : Under this reportable disease, only CDI outbreaks in long-term care homes (LTCHs) are included in this report. 5: Chronic Case (Carrier) classification added in : These diseases were added to the Ontario Reportable Disease List on December 4, : Both confirmed and probable cases of these diseases are included in this report. 8: Probable classification became reportable as of January 2013, but probable cases are not included in this report; refer to the Case Classifications section above for more details. Reportable Disease Trends in Ontario,

207 Public Health Ontario 480 University Avenue, Suite 300, Toronto, Ontario M5G 1V