Action requested:
- Be aware that influenza is now circulating in the community (see Figure 1 below).
- Encourage unvaccinated patients to get vaccinated as soon as possible, particularly those predisposed to severe illness or complications (e.g., ages 2 and younger or 65 and older; cardiopulmonary, metabolic, or neurologic conditions).
- Follow your facility’s influenza testing protocols.
- If you have no such protocols and a rapid test is available in your setting, pursue testing when the results would affect the clinical or infection control management of the patient (see Figure 2 below).
- Negative results do not exclude the diagnosis in a clinically compatible case.
- Consider treating empirically for influenza with a five-day course of oseltamivir (or an alternate agent if appropriate) when patients present with influenza-like illness—regardless of test results or vaccination status, especially among those predisposed to severe illness or complications.
Figure 1. Number and Percent of Positive Influenza Tests, Sentinel Settings, Snohomish County, 2019-2020.

Source: Snohomish Health District Influenza Surveillance System
Figure 2. Guide for considering influenza testing when influenza viruses are circulating in the community:

Source: Centers for Disease Control and Prevention. https://www.cdc.gov/flu/professionals/diagnosis/considerinfluenza-testing.htm
Background
Reports to the Snohomish Health District show an uptick in influenza in Snohomish County since midNovember. Multiple patients have been hospitalized with influenza-like illness.
It is still early in the season and vaccination is a crucial tool for limiting the spread of influenza and protecting groups who are at higher risk of severe complications.
During the 2018-19 season, 26 influenza-related deaths and 362 hospitalizations were reported in Snohomish County.
The Snohomish Health District works in partnership with local hospitals to track influenza data. Weekly reports are posted online during the season, generally on Fridays. They are available at www.snohd.org/flu.
Resources: