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October 20, 2026

Updated guidance for novel influenza screening and influenza subtyping

➜ This health advisory is also available in PDF format (223 KB)

Current situation

Highly pathogenic avian influenza (HPAI or bird flu) continues to circulate among wild birds and other animals in Washington. Although the risk to the general public remains low, clinicians should remain vigilant for possible avian influenza infections in patients with acute respiratory illness (ARI) and epidemiologic risk factors.

Guidance has changed for the 2026-27 influenza season, summarized below.

Actions requested

  1. Identify

    • Test all patients with ARI AND epidemiologic risk factors for influenza and obtain seasonal influenza subtyping for influenza A-positive specimens. Epidemiologic risk factors include the following within 10 days before symptom onset:
      • Close contact with sick or dead animals or their environments, especially birds, wildlife, livestock (including poultry), or domestic animals suspected of HPAI
      • Consumption or handling of raw animal products or parts from potentially infected animals (e.g., raw cow milk or products made with it, raw meat-based pet food)
      • Close contact (within 6 feet) to someone suspected or confirmed to have avian influenza
    • Influenza A subtyping is NOT requested for patients without epidemiologic risk factors, including hospitalized patients. Note this is a change from previous recommendations.

  2. Test

    • Avian influenza testing is available at WA DOH Public Health Laboratories (PHL) with prior approval from Public Health.
    • If seasonal influenza A subtyping is not available through a clinical or commercial lab, the following specimens may be submitted directly to PHL without pre-approval:
      • All influenza A specimens that result as "unsubtypeable" (influenza A positive test but seasonal influenza A subtype was negative or not identifiable)
      • Specimens from hospitalized patients with risk factors for avian influenza, when seasonal influenza subtyping is not available

  3. Notify

    • Immediately report suspected and confirmed cases of novel influenza to Public Health at 206-296-4774, including patients with ARI and identified epidemiologic risk factors. Do not wait for lab confirmation before notifying us. The following are immediately notifiable:
      • All suspected novel influenza, including avian influenza (influenza A H5 or others); a negative influenza PCR does not rule out avian influenza
      • All influenza A specimens that result as "unsubtypeable"

Resources for providers