Washington State Confirms First-Ever Human Case of Rare H5N5 Bird Flu
In a first-of-its-kind case, Washington state health officials have confirmed that a local resident has been infected with H5N5 — a strain of bird flu previously seen only in animals and never before in humans.
The patient, described only as an older man with underlying health issues, fell seriously ill earlier this month with a high fever, confusion, and severe breathing problems. He was hospitalized and later tested positive for H5N5, a subtype of avian influenza commonly carried by wild birds such as ducks and geese.
According to the Washington State Department of Health, the man kept a backyard flock of poultry at his home in Grays Harbor County, where two birds had recently died. Wild birds were also able to enter the property, and officials believe either the domestic flock or visiting wild birds were the “most likely” source of exposure.
The man remains hospitalized as the investigation continues.
Despite the unprecedented nature of the case, health officials stress that the risk to the general public is low. No other infections have been detected, and there is currently no evidence of human-to-human transmission. Experts caution, however, that viruses can evolve unpredictably.
While H5N5 has never been seen in humans before, other strains like H5N1 have been present in the U.S. since 2022, affecting wild birds, poultry, dairy cattle, and occasionally people. Since 2024, the U.S. has recorded 71 human infections with H5 strains — most mild, though one Louisiana patient died earlier this year.
As for the Washington case, officials say it appears tied to backyard chickens exposed to wild birds, a pattern seen in previous infections. Public health agencies continue to monitor the situation closely.