The Washington State Department of Health announced on 22/11 that the patient was elderly and had multiple underlying health conditions, according to AP. The individual resided in Grays Harbor County, approximately 125 km southwest of Seattle, and kept backyard poultry that had contact with wild birds.

H5N5 is an influenza virus strain previously documented only to infect poultry, with no prior human infections until this case.

"The risk of infection to the community is low, as no close contacts of the patient have tested positive for avian influenza", stated the Department of Health's communique on 21/11.

Illustration: SBS.

Illustration: SBS.

Health officials continue to monitor close contacts of the patient, but "there is no evidence indicating human-to-human transmission of this virus".

The US Centers for Disease Control and Prevention (CDC) also announced the infection, stating there is no information to suggest "an increased public health risk due to this case".

The H5N5 strain is not considered a significant threat to human health compared to the H5N1 virus. In 2024 and 2025, the US recorded 70 H5N1 infections, primarily among workers on dairy and poultry farms, with most experiencing mild illness.

Binh Minh (According to AP)