California confirms two human cases of bird flu in California
The California Department of Public Health (CDPH) announced that a dairy worker with mild symptoms who had contact with infected cows in the Central Valley has tested positive for H5N1 avian influenza in preliminary tests at a public health laboratory. The individual is a worker at a Central Valley dairy facility experiencing an outbreak of bird flu among dairy cattle. The individual experienced mild symptoms, reporting only conjunctivitis. Once the local health department was notified, their public health laboratory tested the individual for H5N1, and CDPH was notified of a “presumptive positive” result. Specimens have been forwarded to the CDC for confirmatory testing. In accordance with CDC guidance, the individual is being treated with antiviral medication and is staying home.
Like the first case, the second individual has also experienced mild symptoms, including conjunctivitis, and neither reported respiratory symptoms, nor was hospitalized.
These are the first human cases of bird flu identified in the state and are both in Central Valley individuals who had contact with infected dairy cattle.There is no known link or contact between the two cases, suggesting only animal-to-human spread of the virus in California.
The CDC statement: CDC has confirmed two human cases of H5 bird flu from specimens submitted by California. The cases occurred in people with occupational exposure to infected dairy cows. At this time, there is no known link or contact between the first and second confirmed cases in California, suggesting these are separate instances of animal-to-human spread of the virus. These are the first human cases of H5 in California, where H5N1 outbreaks among dairy herds were first reported in August 2024. 16 human cases of H5 have been reported in the United States during 2024, bringing the total to 17 cases since 2022. Cases during 2024 have been reported in Texas (1), Michigan (2), Colorado (10), Missouri (1) and California (2). Six of the 16 reported human cases have been linked to exposure to sick or infected dairy cows. Nine cases had exposure to infected poultry.
