Influenza A (H1N1)pdm09 in Minnesota Epidemiology Infectious Disease Epidemiology, Prevention and Control Division PO Box 64975 St. Paul, MN 55164-0975
Number of Influenza Hospitalizations by Influenza Type, Minnesota, October 2008 April 2010 Number of Hospitalizations 450 425 400 375 350 325 300 275 250 225 200 175 150 125 100 75 50 25 0 A/B (rapid test only) B (rapid test only) A (rapid test only) Seasonal B Untypeable A [likely A (H1N1)pdm09] A (H1N1)pdm09 Seasonal A 2008-2009 Influenza Season October 1, 2008 April 30, 2009 1 st A (H1N1)pdm09 hospitalized case Spring Influenza Surveillance May 1, 2009 August 31, 2009 40 43 46 49 52 2 5 8 11 14 17 20 23 26 29 32 35 38 41 44 47 50 1 4 7 10 13 16 Week of Specimen Collection 2009-2010 Influenza Season September 1, 2009 April, 2010
Number of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases, Minnesota, April 2009 April 2010 400 350 Number of Hospitalizations 300 250 200 150 100 50 0 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Week of Specimen Collection
Cumulative Incidence of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases, Minnesota, April 2009 - April 2010 40 Hospitalizations per 100,000 Persons 35 30 25 20 15 10 5 0 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 2 4 6 8 0 12 14 16 Week of Specimen Collection
10 9 Percentage of Outpatient Visits for ILI* among Sentinel Surveillance Sites, by Season, Minnesota, September 2007 April 2010 07-08 Season 08-09 Season 09-10 Season % of Outpatient Visits for ILI 8 7 6 5 4 3 2 Fall Wave 2009 Normal influenza Surveillance October 1 April 30 Spring Wave 2009 1 0 35 37 39 41 43 45 47 49 51 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 *Influenza-like Illness Week of Clinic Visit
350 Number and Percentage of Schools Reporting Outbreaks of ILI*, Minnesota, September 2009 April 2010 25% Number of Schools 300 250 200 150 100 50 Number of Schools Reporting ILI Percent of Eligible Schools Reporting ILI 20% 15% 10% 5% 0 0% *Influenza-like Illness Week of Outbreak
Number and Percentage of Culture-Confirmed Influenza Specimens, Minnesota Virology Laboratories September 2007 April 2010 200 100 175 Flu A/B+ 90 Number of Positive Culture Tests 150 125 100 75 50 Flu B+ Flu A+ 2009-2010 % + 2008-2009 % + 2007-2008 % + 80 70 60 50 40 30 20 % of Positive Culture Tests 25 10 0 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 0 Week of Specimen Collection
Number and Percentage of Positive Influenza Rapid Test Results, Minnesota Rapid Testing Sites, September 2007 April 2010 1500 100 Number of Positive Rapid Tests 1250 1000 750 500 250 Flu B+ Flu A/B+ Flu A+ 2009-2010 % + 2008-2009 % + 2007-2008 % + 90 80 70 60 50 40 30 20 % of Positive Rapid Tests 10 0 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 0 Week of Specimen Collection
Circulating Respiratory Viruses, Laboratory Influenza Surveillance Program, Minnesota, October 2009 April 2010 200 Number of Positives 180 160 140 120 100 80 60 Adenovirus Enterovirus Influenza A Influenza B Human Metapneumovirus Parainfluenza 1 Parainfluenza 2 Parainfluenza 3 Parainfluenza 4 Rhinovirus RSV 40 20 0 40 42 44 46 48 50 52 2 4 6 8 10 12 14 16 18 Week of Submission
Number and Incidence of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by Age Group, Minnesota, April 2009 April 2010 Number of Hospitalizations 500 450 400 350 300 250 200 150 100 50 Number of Hospitalizations Hospitalizations per 100,000 Persons 120 100 80 60 40 20 Hospitalizations per 100,000 Persons 0 0-4 5-18 19-24 25-49 50-64 65+ Age Group (yrs.) 0
Number and Incidence of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by Race/Ethnicity, Minnesota, April 2009 April 2010 Number of Cases Incidence per 100,000 259 140 45 43.2 26.2 104.2 1,179 83 68.0 73.9 White Black Native American Hispanic Asian
Proportion of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by Race/Ethnicity, Minnesota, April 2009 April 2010 Spring Wave Fall Wave Multi Race Native American Unknown Native American Multi Race Unknown Asian White Asian Hispanic Black Hispanic White Black
Median Age of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by Race/Ethnicity, Minnesota, April 2009 April 2010 Race/Ethnicity Spring Wave Fall Wave White 16.9 yrs. 30.0 yrs. Black 12.3 yrs. 20.3 yrs. Hispanic 5.3 yrs. 8.4 yrs. Asian 5.4 yrs. 11.7 yrs. Native American 48.2 yrs. 36.3 yrs. All Races 11.1 yrs. 26.8 yrs.
Incidence of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by Week, Minnesota, April 2009 April 2010 Hospitalizations per 100,000 Persons 10 9 8 7 6 5 4 3 2 1 0 Fall Wave 7-County Minneapolis-St. Paul Metro Greater Minnesota Spring Wave 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 2 4 6 8 10 12 14 16 Week of Specimen Collection
Number of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases by District of Residence, April 2009 April 2010 Northwest 18 Northeast 129 West Central Grant 57 Douglas Tod d Central 280 t 71 Hennepi n Metro 1025 Southwest 67 South Central 92 Marti n Faribaul t Steele Southeast Dodge 156 Olmste d
Incidence of Hospitalized PCR-confirmed A (H1N1)pdm09 Cases by District of Residence, Minnesota, April 2009 April 2010 Hospitalizations per 100,000 Persons 50 40 30 20 10 0 11.7 40.2 24.9 39.1 36.5 32.1 30.6 32.1
Incidence of Hospitalized PCR-confirmed A (H1N1)pdm09 Cases by District of Residence and Wave, Minnesota, April 2009 April 2010 Hospitalizations per 100,000 Persons 50 40 30 20 10 0 Spring Fall
Hospitalized PCR-confirmed A (H1N1)pdm09 Cases by Age Group and Presence of Underlying Medical Conditions, Minnesota, April 2009 April 2010 Without Underlying Medical Condition With Underlying Medical Condition(s) Adult Pediatric 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Percent of Cases
Underlying Medical Conditions of Hospitalized PCR-confirmed A (H1N1) pdm09 Adult ( 18 yrs.) Cases, Minnesota, April 2009 April 2010 Underlying Medical Condition Total Percent Asthma 328 32% Chronic Metabolic Disease 288 28% Chronic Lung Disease 201 20% Chronic Cardiovascular Disease 225 22% Immunosuppressive Condition 108 11% Cognitive Dysfunction 54 5% Neuromuscular Disorder 62 6% Cystic Fibrosis 7 1% Chronic Renal Disease 92 9% Cancer 30 3%
Underlying Medical Conditions of Hospitalized PCR-confirmed A (H1N1) pdm09 Pediatric (<18 yrs.) Cases, Minnesota, April 2009 April 2010 Underlying Medical Conditions Total Percent Asthma 228 28% Chronic Metabolic Disease 26 3% Chronic Lung Disease 30 4% Chronic Cardiovascular Disease 24 3% Immunosuppressive Condition 32 4% Developmental Delay 65 8% Neuromuscular Disorder 37 5% Cystic Fibrosis 2 <1% Seizure Disorder 39 5%
Proportion of Hospitalized PCR-confirmed A (H1N1)pdm09 Cases Admitted to the ICU by Age Group and Presence of Underlying Medical Conditions, Minnesota, April 2009 April 2010 % of Cases Admitted to ICU 50% 40% 30% 20% 10% 19% All Cases Without Underlying Medical Condition With Underlying Medical Condition(s) 0% Pediatric Adult
Proportion of Hospitalized PCR-confirmed A (H1N1)pdm09 Cases Requiring Mechanical Ventilation by Age Group and Presence of Underlying Medical Conditions Minnesota, April 2009 April 2010 50% % of Cases Requiring Mechanical Ventilation 45% 40% 35% 30% 25% 20% 15% 10% 5% 10% All Cases Without Underlying Medical Condition With Underlying Medical Condition(s) 0% Pediatric Adult
Proportion of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases Diagnosed with Pneumonia by Age Group and Presence of Underlying Medical Conditions, Minnesota, April 2009 April 2010 Without Underlying Medical Condition With Underlying Medical Condition(s) 50% % of Cases with Pneumonia 40% 30% 20% 10% 37% All Cases 0% Pediatric Adult
Proportion of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases with Bacterial Co-Infection* by Age Group and Presence of Underlying Medical Conditions, Minnesota, April 2009 April 2010 % of Cases with Bacterial Co-Infection 10% 8% 6% 4% 2% 1.6% All Cases Without Underlying Medical Condition With Underlying Medical Condition(s) 0% Pediatric Adult *Cultural confirmation of a bacterial pathogen from sterile site within 3 days of admission.
Number and Percentage of Hospitalized PCR-confirmed A (H1N1) pdm09 Cases Ages 13-49 Who Were Pregnant Minnesota, April 2009 April 2010 Spring Wave Fall Wave Total Females 13-49 Yrs. n=54 n=329 n=383 Pregnant Cases 20 (37%) 46 (14%) 66 (17%)
Hospitalized PCR-confirmed A (H1N1) pdm09 Cases in Minnesota: Summary From April 1, 2009 to April 30, 2010: 1,824 hospitalized PCR-confirmed 2009 H1N1 Influenza cases; 1,564 since September 1, 2009 In Spring wave: Median age: 11.8 years 17% admitted to the ICU 81% cases from Minneapolis-St. Paul metropolitan area In Fall wave: Median age: 26.5 years 20% admitted to the ICU 52% cases from Minneapolis-St. Paul metropolitan area Pregnancy among hospitalized women 13-49 years of age: 17% (of 384)
Number of Deaths Related to Influenza A Minnesota, April 2009 April 2010 67 Deaths Related to Influenza A 63 (H1N1) pdm09, 4 Influenza A, Not Subtyped 55 Hospitalized 12 Not hospitalized
Number of Deaths Related to Influenza A by Wave and Age Group, Minnesota, April 2009 April 2010 Age Group (yrs.) Spring Fall Total <18 2 6 8 18-64 1 45 46 65+ 1 12 13 Total Deaths 4 63 67
Deaths Related to Influenza A by Race/Ethnicity, Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A] Hispanic Black Asian Native American White
Influenza A Deaths in Minnesota by Week of Collection, (N=67) Minnesota, April 2009 April 2010 Number of Deaths 13 12 11 10 9 8 7 6 5 4 3 2 1 Metro Northeast Northwest South Central Southeast Southwest Central West Central 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 Jun Jul Aug Sep Oct Nov Dec 51 52 1 2 9 Jan Mar Week of Collection
Influenza A Crude Death Rates by District of Residence, Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A) District Deaths n=67 Crude Death Rate per 100,000 Persons Northwest 2 1.34 Northeast 11 3.43 West Central 2 0.77 Central 7 0.99 Metro* 30 1.07 South Central 5 1.93 Southwest 2 0.91 Southeast 8 1.65 *All 4 deaths in spring wave occurred in Metro district residents
Deaths Related to Influenza A by Age Group and Presence of Underlying Medical Condition(s), Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A] Age Group (yrs.) Deaths % With Underlying Medical Condition(s) <18 8 75.0% 18-64 46 84.8% 65 13 92.3% All Ages 67 87.7%
Underlying Medical Conditions among Deaths Related to Influenza A, Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A] Underlying Medical Condition Total Percent Obesity 30 46.9% Chronic Cardiovascular Disease 27 42.2% Chronic Metabolic Disease 21 32.8% Immunosuppressive Condition 15 23.4% Chronic Lung Disease 11 17.2% Renal Disease 9 14.1% Neuromuscular Disorder 7 10.9% History of Lymphoma/Leukemia 6 9.4% Cognitive Dysfunction 6 9.4% Asthma 6 9.4% Cancer Diagnosis in last 12 months 4 6.3% Seizure Disorder 4 6.3% Pregnant 0 0.0%
Body Mass Index of Adult Deaths Related to Influenza A, Minnesota, April 2009 April 2010 [55=(H1N1)pdm09; 4=unspecified Influenza A] 5% 17% 20% 24% Underweight: <18.5 Normal: 18.5 24.9 Overweight: 25.0 29.9 Obese: 30.0 39.9 Morbidly Obese: 40 Unknown 12% 22%
Clinical Outcomes of Deaths Related to Influenza A by Age Group, Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A) Clinical Outcome Pediatric <18 yrs. n=8 Adult 18+ yrs. n=59 Hospitalized 5 (62.5%) 50 (84.7%) Intensive Care Unit Admission 5 (62.5%) 46 (78.0%) Mechanical Ventilation 6 (75%) 40 (67.8%) Acute Respiratory Distress Syndrome (ARDS) 1 (12.5%) 16 (27.1%) Pneumonia 5 (62.5%) 48 (81.4%) Viral 0 10 (16.9%) Bacterial 1 (12.5%) 3 (5.5%) Both 0 3 (5.5%)
Bacterial Co-Infections in Deaths Related to Influenza A, Minnesota, April 2009 April 2010 [63=(H1N1)pdm09; 4=unspecified Influenza A) Sterile Non-sterile* Combined Total (%) Total (%) Total (%) Persons with Bacterial Co-infection(s) 10 (15%) 10 (15%) 20 (30%) Staphylococcus aureus 5 (7%) 4 (6%) 9 (13%) MRSA 3 (4%) 2 (3%) 5 (7%) MSSA 0 1 (1%) 1 (1%) Unknown 2 (3%) 1 (1%) 3 (4%) Streptococcus pneumoniae 3 (4%) 0 3 (4%) Group B Streptococcus 2 (3%) 4 (6%) 6 (9%) Pseudomonas aeruginosa 1 (1%) 1 (1%) 2 (3%) Bacterial Other** 2 (3%) 7 (10%) 9 (13%) *Non-sterile sites include sputum, endotracheal aspirate, lung tissue, and stool **Stenotrophomonas maltophilia, Enterobacter cloacae, Staphylococcus saprophyticus, Staphylococcus coagulase negative, Enterococcal sepsis, Moraxella catarrhalis, Group A Streptococcus, Escherichia coli, VRE
Summary of Deaths Related to Influenza A, Minnesota, April 2009 April 2010 Spring wave 4 deaths [all PCR-confirmed A (H1N1)pdm09] 2 children; 1 adult (age 65 or older) 1 with no underlying conditions 100% Minneapolis-St. Paul metropolitan area Fall wave 63 deaths [59 A (H1N1)pdm09, 4 Influenza A-type unspecified] 6 children; 12 adults (age 65 or older) 7 with no underlying conditions 41% Minneapolis-St. Paul metropolitan area
For More Information Please Contact: Minnesota Department of Health Acute Disease Investigation and Control 651-201-5414 1-877-676-5414 www.health.state.mn.us