A Grays Harbor County resident being treated for H5N5 avian influenza has died, the Washington State Department of Health said Friday.
The patient, described only as an older adult with underlying health conditions, had been hospitalized in King County since early November.
Out of respect for their family’s privacy, health officials declined to release the person’s name, age or gender.
The department expressed condolences to the family and friends affected by the loss.
According to the Department of Health, this case marks the first known human infection with the H5N5 strain anywhere in the world.
The UW Medicine Clinical Virology Lab identified the virus, and the Centers for Disease Control and Prevention confirmed the result.
State public health officials emphasized that the risk to the public remains low.
No additional people connected to the case have tested positive for avian influenza, and officials say there is no evidence that this virus spreads between people.
Anyone who had close contact with the patient or their animals is being monitored for symptoms as a precaution.
Investigators say the resident kept a backyard flock of mixed domestic birds.
Samples collected from the property showed avian influenza virus in the environment, which health officials say makes exposure to domestic poultry, the flock’s surroundings, or wild birds the most likely source of the infection.
People who had contact with the flock are also being monitored.
Avian influenza viruses occur naturally in wild aquatic birds and can spread to domestic poultry, where they can cause severe illness.
The viruses occasionally infect mammals, including people, though such cases are rare.
State agencies urged anyone who raises backyard birds to avoid handling sick or dead poultry and to report illnesses to the Washington State Department of Agriculture at 1-800-606-3056 or through the agency’s online portal.
You can learn more information from the Department of Health here.
Veterinarians are asked to report any domestic animals or livestock suspected of bird flu infection, and the Washington Department of Fish & Wildlife encourages the public to report sick or dead wild birds.
Officials also reminded people to avoid touching dead wildlife, to keep pets away from carcasses, and to refrain from eating raw or undercooked foods such as unpasteurized milk or raw cheeses.
The Department of Health reiterated the importance of seasonal flu vaccination for anyone who may be exposed to domestic or wild birds.
While the vaccine does not prevent bird flu, it helps reduce the risk of being infected with both human and avian influenza at the same time — a combination that could theoretically allow new, more easily transmissible viruses to emerge.
Flu shots are recommended for everyone 6 months and older.
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