The woman had a backyard flock of chickens that got sick and died, a CDC spokesperson said Saturday. The state health department said the woman, who lives in Platte County, Wyoming, likely had direct contact with the flock. It said she also has other health conditions and is hospitalized in another state.

The patient was experiencing "flu-like symptoms" and had "health conditions that can make people more vulnerable to illness," Wyoming's health department said. She was likely exposed to the H5N1 virus through direct contact to an infected poultry flock at her home.

With so much H5N1 circulating in the U.S., scientists worry we are a few mutations away from a potential human pandemic.

The study published Thursday by the Centers for Disease Control and Prevention echoes two smaller ones that detected evidence of infection in previously undiagnosed farmworkers. In those studies, several of the infected workers remembered having symptoms of H5N1 bird flu, while none of the veterinarians in the new paper recalled any such symptoms.

In February 2024, government veterinarians in the Czech Republic investigating a bird flu outbreak found themselves in the middle of a puzzling case.

As the popularity of keeping backyard and urban chicken flocks grows, health and agriculture experts warn that bird flu can pose a risk to your feathered friends — and by extension, a small risk to you,

The latest CDC tracking data on bird flu suggests the virus may be spreading undetected among humans. Dr. Celine Gounder has the latest.

Wyoming’s first case of H5N1 avian influenza in a human has been confirmed in a Platte County older adult, according to the Wyoming Department of Health (WDH).