First human case of Avian Flu confirmed in U.S. since February

Health authorities have confirmed the first human case of avian influenza in the United States since February, marking a significant development in the ongoing monitoring of bird flu.

David Corredor

Health authorities have confirmed the first human case of avian influenza in the United States since February, marking a significant development in the ongoing monitoring of bird flu. The case involves an older adult from Grays Harbor County, Washington, who tested positive for the H5N5 strain—a variant previously detected in animals but never before in humans. This confirmation represents not only the first U.S. case in nine months but also the first documented human infection with H5N5 globally.

• According to the Washington State Department of Health, the patient developed severe symptoms in early November, including high fever, confusion, and respiratory distress, and was hospitalized shortly thereafter.
• Officials reported that the individual had underlying health conditions and maintained a mixed backyard flock of domestic poultry, which had been exposed to wild birds.
• Investigators believe this contact is the most likely source of infection, though the exact transmission route remains under review.

Laboratory tests confirmed the presence of H5N5, a highly pathogenic avian influenza virus similar to the more widely known H5N1 strain. While H5N1 has caused sporadic human infections worldwide, H5N5 had never crossed the species barrier until now. Experts emphasize that there is no evidence of human-to-human transmission, and the Centers for Disease Control and Prevention (CDC) maintains that the overall risk to the public remains low.

• This case underscores the importance of continued surveillance as avian influenza persists among wild birds and poultry across the United States.
• Washington state has reported multiple detections of bird flu in recent weeks, reflecting a broader national trend.
• Health officials urge poultry owners and wildlife handlers to exercise caution, avoid contact with sick or dead birds, and use protective equipment when necessary.

The emergence of H5N5 in humans raises questions about viral evolution and zoonotic potential. Although current assessments suggest minimal public health risk, scientists are closely monitoring the situation to understand whether this strain could adapt further. For now, authorities stress that preventive measures and rapid reporting remain key to limiting exposure and preventing future cases.