Bird flu is a disease caused by avian influenza A viruses, according to the CDC. The virus mostly spreads between birds and dairy cows, but there have been 67 human cases of bird flu nationwide and one death tied to the infection since 2024, CDC records show.

The CDC has confirmed a new human H5N1 bird flu case in California, raising the US total to 67. Most cases involve farm workers exposed to sick animals. The CDC urges rapid testing, antiviral treatments,

The Centers for Disease Control and Prevention says hospitals treating people for the flu should test them for avian influenza within 24 hours.