California Governor Gavin Newsom has declared a state of emergency due to H5N1, more commonly known as avian influenza or bird flu.
The emergency follows an outbreak of the virus among dairy cows in Southern California farms, according to the news release on the governor's website.
After initially being reported in Texas and Kansas in March, bird flu has been confirmed in cattle across 16 U.S. states, as the Centers for Disease Control and Prevention (CDC) has reported.
There have been no cases of human transmission of bird flu in California, the release stated, with all infections linked to exposure to infected cattle.