California and federal health officials on Thursday said two farm workers tested positive for bird flu they contracted from infected dairy cows. File Photo by Scott Bauer/Agricultural Research Service
Two California farm workers have tested positive for bird flu, federal health officials said Thursday, marking the first two human cases of the virus in the state.
The U.S. Center for Disease Control and Prevention said in a release that both patients became infected with H5N1 bird flu through occupational exposure to infected dairy cows. Advertisement
There is no link between the cases, according to the CDC, which said this suggests two separate instances of animal-to-human spread of the virus.
“CDC continues to collaborate closely with California and other state public health officials to support state-run efforts to control the spread of H5N1 from infected animals to humans,” it said in the release.
The announcement came after the California Department of Public Health reported the cases to the public, stating that both are Central Valley residents, and at least one had worked at a dairy facility experiencing an outbreak of the disease among cattle.
Both patients experienced mild symptoms, including conjunctivitis, and neither reported respiratory symptoms nor were hospitalized, it said.
“The risk to the general public remains low, but people who interact with infected animals, like dairy or poultry farm workers, are at higher risk of getting bird flu,” the CDPH warned in a release, while informing the public that pasteurized milk and dairy products continue to be safe to consume. Advertisement
Outbreaks of H5N1, as the bird flu variant is known, were detected among diary herds in California in August, with the first dairy case confirmed in the United States on March 24.
The CDC confirmed an H5N1 infection in a person with exposure to dairy cows in Texas, which is presumed to be the first instance of likely mammal to human spread of the virus.
In May, it began reporting additional sporadic human cases with exposure to dairy cows.
According to CDC statistics, there have been 14 reported human bird flu cases in the United States since March, and 15 since 2022, when the United States’ first case was detected. Four total cases were due to exposure to diary cows, 10 from poultry and one from an unknown source, it said.
The CDC said that 254 diary herds have been infected.
Despite the cases, the CDC maintains risk to the general public remains low.