Weekly Influenza & Respiratory Illness Activity Report A summary of influenza surveillance indicators prepared by the Division of Infectious Disease Epidemiology Prevention & Control Week Ending April 28, 218 WEEK 17 All data are preliminary and may change as more information is received Minnesota Influenza Geographic Spread No Activity Sporadic Local Regional Widespread During the week ending April 28, 218 (Week 17), surveillance indicators showed local geographic spread of influenza. Since the start of the influenza season, five pediatric influenza-related deaths have been reported. Based on CDC s Activity Estimates Definitions: http://www.cdc.gov/flu/weekly/overview.htm Minnesota Influenza Surveillance: http://www.health.state.mn.us/divs/idepc/diseases/flu/stats/ Weekly U.S. Influenza Surveillance Report: http://www.cdc.gov/flu/weekly/ World Health Organization (WHO) Surveillance: http://www.who.int/influenza/surveillance_monitoring/updates/en/ Neighboring states influenza information: Iowa http://www.idph.state.ia.us/idpharchive/archive.aspx?channel=flureports Wisconsin http://www.dhs.wisconsin.gov/communicable/influenza/surveillance.htm North Dakota http://www.ndflu.com/default.aspx South Dakota http://doh.sd.gov/diseases/infectious/flu/ Minnesota Department of Health 651-21-5414 or 1-877-676-5414 www.health.state.mn.us 5/3/218
Hospitalized Influenza Surveillance Hospitalized influenza cases are based on disease reports of laboratory-positive influenza (via DFA, IFA, viral culture, EIA, rapid test, paired serological tests or RT-PCR) and specimens from hospitalized patients with acute respiratory illness submitted to MDH-PHL by hospitals and laboratories. Due to the need to confirm reports and reporting delays, consider current week data preliminary. Hospitalized Influenza Cases by Type Minnesota (FluSurv-NET*) Hospitalized Influenza Cases by Season, Minnesota (FluSurv-NET*) 75 7 65 6 55 5 45 4 35 3 25 2 15 1 5 4 42 44 46 48 5 52 2 4 6 8 1 12 14 16 18 2 Hospitalizations this week *Influenza Surveillance Network Hospitalizations last week B (no genotype) B (Yamagata) B (Victoria) A (not subtyped) A H3 A H1 (unspecified) A (H1N1)pdm9 A (H1N2v) A (H3N2v) A&B Unknown Total hospitalizations (to date) 22 52 6,341 Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 2 75 7 65 6 55 5 45 4 35 3 25 2 15 1 5 4 42 44 46 48 5 52 2 4 6 8 1 12 14 16 18 2 Season Total hospitalizations (historic) 212-213 3,75 213-214 1,578 214-215 4,81 215-216 1,538 216-217 3,695 217-218 6,341 (to date) 212-13 213-14 214-15 215-16 216-17 217-18
Hospitalized Influenza Surveillance (continued) Number of Influenza Hospitalizations and Incidence by Region, Minnesota October 1, 217 April 28, 218 5 45 4 35 3 25 2 15 1 5 12.7 Region 123.2 15.5 85.1 Region Hospitalizations this week # of hospitalizations Incidence (cases) per 1, Persons 13.6 18.5 18. 8.6 Total (to date) 5. 45. 4. 35. 3. 25. 2. 15. 1. 5.. Hospitalizations per 1, Persons Central 1 (5%) 77 (12%) Metro 9 (41%) 3,738 (59%) 73. Northeast 8 (36%) 343 (5%) Northwest 1 (5%) 135 (2%) South Central (2%) 379 (6%) Southeast 1 (5%) 547 (9%) Southwest 1 (5%) 235 (4%) West Central 1 (5%) 194 (3%) Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 3 Number of Influenza Hospitalizations and Incidence by Age, Minnesota October 1, 217 April 28, 218 5 45 4 35 3 25 2 15 1 5 59. # of hospitalizations Incidence (cases) per 1, Persons 25.1 33.5 93.1 496.7-4 5-24 25-49 5-64 65+ Age Group (years) Median age (years) at time of admission 5. 45. 4. 35. 3. 25. 2. 15. 1. 5.. Hospitalizations per 1, Persons
Respiratory Disease Outbreak Surveillance School Outbreaks K-12 schools report an outbreak of influenza-like illness (ILI) when the number of students absent with ILI reaches 5% of total enrollment or three or more students with ILI are absent from the same elementary classroom. 3 Influenza-like Illness (ILI) in Schools by Season Number of influenza-like illness outbreaks 25 2 15 1 5 4 41 42 43 44 45 46 47 48 49 5 51 52 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 213-14 214-15 215-16 216-17 217-18 New school outbreaks this week New school outbreaks last week Total this season (to date) 8 695 Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 4
Respiratory Disease Outbreak Surveillance (continued) Long-Term Care (LTC) Outbreaks LTC facilities report to MDH when they suspect an outbreak of influenza in their facility. Laboratory-confirmed outbreaks are reported here. Confirmed Influenza Outbreaks in LTC by Season 5 Number of lab-confirmed outbreaks 45 4 35 3 25 2 15 1 5 4 41 42 43 44 45 46 47 48 49 5 51 52 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 New LTC outbreaks this week New LTC outbreaks last week Total this season (to date) 28 213-14 214-15 215-16 216-17 217-18 Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 5
Sentinel Provider Surveillance (Outpatients) MDH collaborates with healthcare providers who report the total number of patients seen and the total number of those patients presenting to outpatient clinics with influenza-like illness. Percentage of Persons Presenting to Outpatient Clinics with Influenza-Like Illness (ILI) Percent with Influenza-like Illness 9 8 7 6 5 4 3 2 1 213-14 214-15 215-16 216-17 217-18 4 41 42 43 44 45 46 47 48 49 5 51 52 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 % of outpatients with ILI this week % of outpatients with ILI last week 1.8% 2.1% * Indicates current week-data may be delayed by 1 or more weeks Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 6
Laboratory Surveillance The MN Lab System (MLS) Laboratory Influenza Surveillance Program is made up of more than 31 clinic- and hospital-based laboratories, voluntarily submitting testing data weekly. These laboratories perform rapid testing for influenza and Respiratory Syncytial Virus (RSV). Significantly fewer labs perform PCR testing for influenza and three also perform PCR testing for other respiratory viruses. MDH-PHL provides further characterization of submitted influenza isolates to determine the hemagglutinin serotype to indicate vaccine coverage. Tracking the laboratory results assists healthcare providers with patient diagnosis of influenza-like illness and provides an indicator of the progression of the influenza season as well as prevalence of disease in the community. Specimens Positive for Influenza by Molecular Testing*, by Week Number of positive molecular tests 12 11 1 9 8 7 6 5 4 3 2 1 B A (not subtyped) A H3 A (H1N1) pdm9 214-15 % + by PCR 215-16 % + by PCR 216-17 % + by PCR 217-18 % + by PCR 35 3 25 2 15 1 5 Percent of positive molecular tests 4 41 42 43 44 45 46 47 48 49 5 51 52 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 % molecular tests positive this week % molecular tests positive last week 14.4% 11.3% * Beginning in 216-17, laboratories report results for rapid molecular influenza tests in addition to RT-PCR results Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 7
Laboratory Surveillance (continued) MLS Laboratories Influenza Testing Specimens Positive by Influenza Rapid Antigen Test, by Week MLS Laboratories RSV Testing Specimens Positive by RSV Rapid Antigen Test, by Week Number of Positive Influenza Specimens 22 2 18 16 14 12 1 8 6 4 2 B+ (217-18 Season) A+ (217-18 Season) A/B+ (217-18 Season) 214-15% + 215-16 % + 216-17 % + 217-18%+ 4 42 44 46 48 5 52 2 4 6 8 1 12 14 16 18 2 5 45 4 35 3 25 2 15 1 5 Percentage of Rapid Antigen Influenza Tests Positive Number of Positive RSV Tests 2 175 15 125 1 75 5 25 Number + 214-15 % + 215-16 % + 216-17 % + 217-18 %+ 4 42 44 46 48 5 52 2 4 6 8 1 12 14 16 18 2 75 7 65 6 55 5 45 4 35 3 25 2 15 1 5 Percentage of Rapid Antigen RSV Tests Positive Region % rapid antigen influenza tests + (current week) Northeast 14% South Central 2% Southwest 18% Southeast 17% Metro 17% Central 13% West Central --- Northwest 29% State (overall) 17% Region % rapid antigen RSV tests + (current week) Northeast % South Central % Southwest 14% Southeast % Metro 5% Central 25% West Central % Northwest --- State (overall) 7% Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 8
Hospitalized RSV Surveillance Surveillance for respiratory syncytial virus (RSV) began in September 216. Hospitalized inpatients of all ages who reside in the 7-county Twin Cities metropolitan area (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott, and Washington) with laboratory-confirmed RSV are reportable. Due to the need to confirm reports and reporting delays, consider current week data preliminary. 1 9 8 7 6 5 4 3 2 1 4 42 44 46 48 5 52 2 4 6 8 1 12 14 16 18 2 Hospitalizations this week Hospitalized RSV Cases by Subtype, Minnesota Hospitalizations last week RSV A RSV B RSV, Unspecified Total hospitalizations (to date) 2 7 169 Number of RSV Hospitalizations and Incidence by Age, Minnesota 8 7 6 5 4 3 2 1 422.6 38.1 4.8 1.9 6. 15.6 <2 2-4 5-17 18-49 5-64 65+ Age Group (years) # of hospitalizations Incidence (cases) per 1, Persons Median age at time of admission 11.5 months 45. 4. 35. 3. 25. 2. 15. 1. 5.. Hospitalizations per 1, Persons Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 9
Weekly U.S. Influenza Surveillance Report 217-218 Influenza Season Week 16 ending April 21, 218 National Influenza Surveillance (CDC): http://www.cdc.gov/flu/weekly/ During week 16 (April 15-21, 218), influenza activity decreased in the United States. Viral Surveillance: Overall, influenza A(H3) viruses have predominated this season. Since early March, influenza B viruses have been more frequently reported than influenza A viruses. The percentage of respiratory specimens testing positive for influenza in clinical laboratories decreased. Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the system-specific epidemic threshold in the National Center for Health Statistics (NCHS) Mortality Surveillance System. Influenza-associated Pediatric Deaths: Four influenza-associated pediatric deaths were reported. Influenza-associated Hospitalizations: A cumulative rate of 15.3 laboratory-confirmed influenza-associated hospitalizations per 1, population was reported. Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 1.7%, which is below the national baseline of 2.2%. One of 1 regions reported ILI at or above their region-specific baseline level. Three states experienced low ILI activity; and New York City, the District of Columbia, Puerto Rico, and 47 states experienced minimal ILI activity. Geographic Spread of Influenza: The geographic spread of influenza in four states was reported as widespread; Guam, Puerto Rico and nine states reported regional activity; 25 states reported local activity; the District of Columbia, the U.S. Virgin Islands and 1 states reported sporadic activity; and two states reported no influenza activity. A Weekly Influenza Surveillance Report Prepared by the Influenza Division Weekly Influenza Activity Estimates Reported by State and Territorial Epidemiologists* A Weekly Influenza Surveillance Report Prepared by the Influenza Division Influenza-Like Illness (ILI) Activity Level Indicator Determined by Data Reported to ILINet *This map indicates geographic spread and does not measure the severity of influenza activity. Minnesota Department of Health Weekly Influenza & Respiratory Activity Report for Week Ending April 28, 218 WEEK 17 1