Approved - Health and Social Services - Oct 20, 2009 Adopted - Regional Council - Oct 28, 2009 The Regional Municipality of Halton Report To: From: Chair and Members of the Health and Social Services Committee Bob Nosal, Commissioner and Medical Officer, Health Date: September 28, 2009 Report No. - Re: MO-50-09 - 2008 Halton Region Infectious Disease Report RECOMMENDATION REPORT Purpose THAT Report No. MO-50-09 re: 2008 Halton Region Infectious Disease Report be received for information. The purpose of this report is to highlight key findings in relation to the 2008 Infectious Disease Report (Report distributed under separate cover). Background In Ontario under the authority of the Health Protection and Promotion Act (HPPA), certain infectious diseases must be reported to and investigated by the local public health unit. The list of reportable diseases is updated periodically. The 2008 list is included in Appendix A of the full report. The 2008 Halton Region Infectious Disease Report reflects the surveillance and health status reporting function that the Health Department is mandated to perform in order to monitor the impact of infectious disease programs and to identify significant or emerging issues. The Health Department works towards the goal of reducing the incidence of infectious diseases in the community through the delivery of various program components. Staff investigate reports of individual cases and respond to outbreaks in both the community and in institutions such as longterm care homes, child care settings, schools, colleges and prisons. In addition to investigating disease reports and preventing further spread of disease, the Department also conducts inspections to prevent disease, including inspections of licensed child care settings, personal services settings, food premises and swimming pools. The Health Department is also mandated to prevent and reduce the burden of infections through education, certification programs, and the provision of various clinical services such as immunization clinics, sexual health clinics and travel health clinic services. 1
The 2008 Infectious Disease Report highlights the top ten most common diseases for Halton Region, and shows the trends for diseases which are commonly reported to the Health Department. In this summary report MO-50-09, chlamydia is discussed because it is the most commonly reported disease and the incidence of this disease is rising. Streptococcus pneumoniae is highlighted because of the emergence of antibiotic resistant bacteria. Outbreaks involving Halton Region and other health units are described, as well as the proposed new national system for case management and reporting. Chlamydia Chlamydia is the most commonly reported sexually-transmitted infection (STI), and a significant public health problem noted internationally, in Canada and in Ontario, including in Halton Region. In 2008, 535 cases of chlamydia were reported for Halton Region residents 356 females and 179 males. Table 1 shows the increase in the number of reported chlamydia cases in the last 10-year period. Table 1. Number of reported chlamydia cases in Halton Region, by year, 1999 to 2008. Year 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Number of cases 142 214 235 250 304 389 390 459 397 535 The age standardized incidence rates of chlamydial infections in Halton showed a rising trend between 1999 and 2008 (Fig. 1). In Halton, the rates increased 204% between 1999 and 2008, from 46.3 to 140.9 per 100,000 residents. Halton's chlamydia rates followed the general upward trend experienced in Ontario overall, but Halton s rates remained significantly below the provincial rates. In 2008, the age standardized incidence rate for chlamydia was 226.1 per 100,000 people in Ontario, compared to 140.9 cases per 100,000 people in Halton Region. 2
250.0 Std. Incidence Rate/100,000 200.0 150.0 100.0 50.0 0.0 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Halton Ontario Figure 1: Chlamydia, age standardized rates per 100,000 population, Halton and Ontario, 1999 to 2008. Some of this noted increase may be attributed to improved screening and testing methods. The introduction of a urine test made it easier to test for chlamydia in males than before. Some of the increased disease incidence may also be explained by an emphasis on screening asymptomatic high risk individuals. However, chlamydia is a hidden epidemic due to lack of awareness of the problem and because the majority of cases are asymptomatic but still infectious. Most cases occur in young adults, and females are more likely to be diagnosed with chlamydia than males, since females are more likely to be tested than males (Figure 2). 160 140 120 Count 100 80 60 Male Female 40 20 0 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 Age Group Figure 2: Number of reported chlamydia cases, by age and sex, for Halton Region residents, 2008. 3
Awareness raising initiatives continue to be critical components of promotional strategies targeting the importance of safer sex practices and testing for sexually transmitted infections. Untreated chlamydia infection puts women at risk for severe reproductive health complications. Chlamydia is the leading cause of pelvic inflammatory disease, chronic pelvic pain, ectopic pregnancy and preventable infertility in women. The risk of adverse complications of chlamydia infection increases with repeat infections (Sexually Transmitted Infections Case Management and Contact Tracing Best Practices Recommendations, MOHLTC April 2009). Similar rising trends are reported for other sexually transmitted infections, such as gonorrhea. Gonorrhea is the next most common STI, but the number of reported gonorrhea cases is far fewer than chlamydia cases (61 cases of gonorrhea versus 535 cases of chlamydia in 2008, in Halton). However there is increasing concern over gonorrheal infections because of increasing cases of antibiotic resistance in Ontario (Ota et al. CMAJ 180(3):287-290, Feb 3 2009). This highlights the importance of prevention of disease rather than relying solely on treatment. Invasive Streptococcus pneumoniae Streptococcus pneumoniae is the leading cause of bacteremia (sepsis/blood poisoning), meningitis (infection of the brain s lining), bacterial pneumonia, and acute otitis media (middle ear infection). Invasive pneumococcal disease is most commonly found in the very young, the elderly and certain high risk populations (Figure 3). 4 3.5 Average number per year 3 2.5 2 1.5 1 0.5 0 0 1-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+ Age group Figure 3: Average number of reported Streptococcus pneumoniae infections in Halton Region, by age group, per year between 2005 and 2008. Streptococcus pneumoniae is a vaccine preventable disease. Since 2005 the vaccine has been available for infants throughout Canada as part of routine infant vaccination programs and has been available to adults with chronic medical conditions and for adults 65 years and older since 1983. 4
Invasive pneumococcal disease became reportable in 2001. In Halton Region, in 2008, there were 31 reported cases of invasive Streptococcus pneumoniae an average of 27 a year over the past 5 years. The incidence rate in Halton Region in 2008 was 6.3 new cases a year per 100,000 people, and this rate was similar to the Ontario rate of 7.2 per 100,000 people per year. Halton rates fluctuate because of the small numbers (Figure 4). 9.0 8.0 Std. Incidence Rate/100,000 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 2001 2002 2003 2004 2005 2006 2007 2008 Halton Ontario Figure 4: Invasive Streptococcus pneumoniae, age standardized rates per 100,000 population, Halton versus Ontario. Note: S. pneumoniae only became reportable to Ontario public health at the end of 2001 and the vaccine became available in 2005. It is important to track the disease to monitor vaccine effectiveness and disease behaviour, especially since the emergence of multi-drug resistant strains. The Ministry of Health and Long- Term Care recently heightened surveillance of this disease by requesting centralized laboratory sub-typing of confirmed samples of Streptococcus pneumoniae. Halton Region in 2008 had one known case of drug-resistant Streptococcus pneumoniae in a child in the 1 to 4 year age group. Outbreaks Although many infectious disease investigations involve single, sporadic cases (that cannot be linked to other cases), contaminated food or water or person-to-person contact can result in clusters of illness affecting large numbers of people. The 2008 Infectious Disease Report summarizes the outbreaks in Halton Region in 2008 that were investigated by the Health Department. The outbreaks described below were of particular interest because of the organisms causing the outbreak and because each of these outbreaks involved several health departments and assistance by both provincial and federal infectious disease control consultants. 5
1. Escherichia coli (E. coli) In October-November 2008, Halton Region Health Department investigated a Halton restaurant involved in a multi-jurisdictional outbreak of E. coli O157:H7. Although the source of the outbreak was never confirmed, there was a plausible hypothesis. The same strain of verotoxinproducing E. coli O157:H7 was confirmed in 29 cases of human illness across the affected health units. In Halton there were 6 confirmed cases, 6 probable cases and 39 suspected cases. Due to the nature of this outbreak it was impossible to obtain food samples from the exact time period of exposure, therefore, the exact source of the outbreak could not be confirmed. Such simultaneous samples of uneaten food, if found to contain the same subtype of pathogen as found in ill persons' stool samples, are normally considered to provide the strongest evidence of a causal link between exposure to a contaminated food and consequent human illness. Findings from this investigation and that of the restaurant-associated outbreaks in three other southern Ontario public health unit jurisdictions suggest that a batch of romaine lettuce, which originated in southern California, with some or all being contaminated with E. coli O157:H7, was delivered to the food premises. Consumption of the contaminated lettuce, or of foods that became contaminated after coming into contact with the contaminated lettuce directly or indirectly (e.g., via common bath water used for rinsing, work surfaces, utensils, or other equipment during handling at the restaurant), is the most likely explanation of the cause of human illness associated with the outbreak in Halton. The outbreak was declared over on November 19, 2008, following two maximum incubation periods for E. coli O157:H7 illness dated to the last possible date of exposure at the food premises. 2. Listeria In late July 2008, routine surveillance of public health data conducted by the Infectious Disease Branch of the Ontario Ministry of Health and Long-Term Care (MOHLTC) detected an increase in the number of listeriosis cases being reported by multiple health units across Ontario. Halton had two cases reported within a one week time period from the same institution. Halton typically sees one case a year. This alerted staff to investigate the kitchen as a potential source of exposure. An inspection of the kitchen and three follow-up food samples were taken as part of the investigation on July 28, 2008. Halton was notified by the MOHLTC of positive laboratory results of the samples on August 12th. Halton issued a same day advisory to all long term care homes, retirement homes and hospitals to put all cold cut products on hold pending further investigation. A national recall followed several days later. The recall continued to expand over the next several weeks. There were a total of 41 cases of human illness in Ontario related to this outbreak and 16 deaths for which listeriosis was an underlying or contributing cause. There were no deaths in Halton during this outbreak. Both provincial and federal investigations were launched to review the timing of the public notifications and the issues associated with the multi-jurisdictional response. Published reports were released and Halton was cited in both the provincial and federal reports for its early advisory. 6
3. Measles Although measles is a highly infectious viral infection, it is a vaccine preventable disease. In Ontario, measles vaccine is provided free of charge and current recommendations include 2 doses of measles, mumps and rubella vaccine (MMR) at 12 and 18 months of age. However, rare cases of measles do occur in both children and adults especially in under-immunized populations. Infection may be introduced by an infected traveller from a country where measles vaccination is not routinely provided. In March 2008, substantial time for case and contact management as well as control efforts to reduce the spread of this disease were required as part of the local public health response when a single case of measles was identified in Halton. This case was part of a provincial outbreak of 23 cases with a common viral genotype, and involved seven health units. Investigation of possible exposures for the case in Halton helped to identify a common exposure for many of the provincial cases. The majority of cases were not immunized (Canadian Communicable Disease Report, July 4, 2008). Panorama: A New Reporting System for Infectious Diseases Since 2005, health units across Ontario have collected data on all 64 reportable diseases through the integrated Public Health Information System (iphis). This data is used to track the occurrence of infectious diseases and to identify emerging public health issues in order to respond quickly to health emergencies. This Ontario-wide system aided in the outbreaks summarized above that involved more than one health unit. The province recognized iphis as an interim solution and in 2007 announced Panorama, the next generation of technology to collect and report health information to the MOHLTC. The new system is intended to be a national system and to cover more than case management, outbreak management and reporting, which are currently addressed by iphis. Panorama will also be a comprehensive documentation and reporting system for immunizations and vaccine inventories. Ontario s implementation of Panorama is aligned with the government s e-health strategy, which supports a stronger information technology system to link health care providers, public health and the MOHLTC. The goal is for every person to have an electronic health record (EHR) in Ontario, and Canada, by 2015. An EHR is a record that collects all the information of a patient s care. Security of the records in Panorama will be an important issue. The public health implications of Panorama at Halton Region Health Department will include the ability to conduct surveillance in near real-time. The prompt identification of infectious disease through receipt of positive electronic laboratory results will improve the ability to recognize outbreaks earlier and assist in all case management. The ability to conduct timely surveillance is an important tool for assessing the impact of infectious diseases on our community s health, and the new Panorama system should support timely and effective local responses to emerging issues, locally, provincially and nationally. However, the exact timing of the implementation of Panorama is not yet known, but it is expected to begin in 2010. There will be resource implications for re-training of staff on a new system, but these cannot be estimated until more information is received from ehealth Ontario. 7
Conclusion Chlamydia is the most commonly reported disease and like other sexually transmitted infections, incidence is rising for a number of reasons. The need to prevent infectious diseases is becoming even more important with the emergence of antibiotic resistant bacteria, as described for gonorrhea and Streptococcus pneumoniae. Outbreak investigations are not always contained within one health unit area, as described for three outbreaks in 2008. The planned Panorama reporting system will make sharing of information between health regions easier, including at a national level. FINANCIAL/PROGRAM IMPLICATIONS Costs for the Health Department s work towards the goal of reducing the incidence of infectious diseases in the community are included in the Health Department s budget. The resource implications for Halton of implementing the new national Panorama system for infectious disease management and reporting, beginning in 2010, are not yet known. RELATIONSHIP TO THE STRATEGIC PLAN This report relates to the Health and Social Services Committee Strategic Plan Theme 3: Create and Improve Safe, Healthy, Liveable, Inclusive Communities, Goal 2: Promote and enhance the delivery of preventive health services. Respectfully submitted, Mary Anne Carson Director, Health Protection Services Robert M. Nosal MD FRCPC Commissioner and Medical Officer of Health Approved by Pat Moyle Chief Administrative Officer If you have any questions on the content of this report, please contact: Mary Anne Carson Tel. # 7863 Joanna Oliver Tel. # 7330 Philippa Holowaty Tel. # 7858 8