For the first time, bird flu has been detected in rats, the U.S. Department of Agriculture (USDA) confirmed, according to a recent report.
Bird flu, otherwise known as H5N1 avian influenza, was found in four black rats in Riverside County, California, where two recent poultry outbreaks were reported.
Officials said the rats were likely infected after exposure to sick birds on nearby farms.
The USDA's update, published Feb. 19, also included previous detections in mice and other mammals, like a fox in North Dakota, a bobcat in Washington state, a mountain lion in Wisconsin, a harbor seal in Massachusetts and two domestic cats in Oregon.
The agency noted the Oregon cat infection was likely tied to raw pet food contaminated with the virus.
The discovery comes as the USDA scrambles to rehire bird flu experts it had recently laid off due to budget cuts. The cuts were recommended by billionaire Elon Musk's Department of Government Efficiency, or DOGE.
"Although several positions supporting [bird flu] were notified of their terminations over the weekend, we are working to swiftly rectify the situation and rescind those letters," the USDA said in a statement to CBS News.
Officials confirmed that veterinarians and emergency response personnel were exempted from layoffs to ensure ongoing efforts to deal with the virus.
Since bird flu began spreading in the U.S. in 2022, more than 162 million birds have been affected, according to the U.S. Centers for Disease Control and Prevention (CDC).
The virus was also detected in dairy cows for the first time in March 2024, and 70 human cases have been reported, mostly among dairy and poultry workers.
One person, a Louisiana resident, has died from the virus, according to the CDC.
More information
The U.S. Centers for Disease Control and Prevention has more on the current bird flu situation.
SOURCE: U.S. Centers for Disease Control and Prevention; CBS News, media report, Feb. 20, 2025