Updated March 14, 2018
Since Oct. 1, we received notification of 416 influenza-related hospitalizations. The median age of hospitalized patients is 67 years and ages ranged from 2 weeks to 100 years. We received notification of 19 influenza-associated deaths. The median age of people who died is 75 years and ages ranged from 44 to 102 years. The last reported influenza-associated death occurred Feb. 23.
Emergency department (ED) and urgent care visits for influenza-like illnesses (ILI) continue to trend downward. Between Oct. 1 and March 3, reporting EDs and urgent care clinics saw 672 people for ILI. Of those, 171 (25%) were ages 5 to 24 years and 222 (33%) were ages 25 to 49 years.
We received notification of 21 influenza outbreaks in long-term care facilities.
For the week ending March 3, we received notification of 165 positive influenza tests (20% of total tests).
These data are preliminary and subject to change.
Washington influenza activity remains elevated. For the week ending March 3, ILI accounted for 2.3% of outpatient visits to ILI Surveillance Network participants, above the 1.1% state baseline. So far in the 2017-2018 season, the state received notification of 211 influenza-associated deaths and 189 outbreaks of ILI in long-term care facilities. For the week ending March 3, 17.9% of state specimens WHO/NREVSS tested were positive for influenza. The Centers for Disease Control and Prevention (CDC) characterized ILI activity in Washington as low and influenza activity as widespread.
U.S. influenza activity decreased during the week ending March 3. Influenza A H3N2 virus is the most common. The proportion of outpatient visits to ILI Surveillance Network participants was 3.7%, above the 2.2% national baseline. CDC received notification of 119 pediatric deaths so far during the 2017-2018 influenza season. For the week ending Feb. 17, the proportion of deaths attributable to pneumonia and influenza was 8.8%, above the epidemic threshold.
Influenza activity in Pierce County, Washington and the U.S. continues to decrease. Unless a substantial change in activity occurs, we will publish influenza updates every other week through the end of the 2017-2018 season.
Centers for Disease Control and Prevention. (March 9, 2018). Weekly U.S. influenza surveillance report—www.cdc.gov/flu/weekly/index.htm.
Washington State Department of Health. (March 9, 2018). Washington influenza update—www.doh.wa.gov/Portals/1/Documents/5100/420-100-FluUpdate.pdf.