Overview
- The Washington State Department of Health said the patient, an older adult with underlying conditions from Grays Harbor County, died on Nov. 21 after being hospitalized in King County since early November.
- UW Medicine’s Clinical Virology Lab identified the virus as H5N5 and the CDC confirmed it, making this the first recorded human infection with this variant globally.
- State environmental sampling detected avian influenza in the patient’s backyard flock area, pointing to exposure from domestic poultry, their environment, or wild birds as the likely source.
- Officials report no evidence of human-to-human transmission, and contacts of the patient and individuals exposed to the flock are being monitored for symptoms.
- The CDC reports roughly 71 U.S. human bird-flu cases in this period, mostly H5N1, with this death being the second in 2025.