USDA Mandates Milk Testing to Track Bird Flu in Dairy Cows

The nationwide testing strategy begins December 16 in six states to combat the spread of the H5N1 virus in livestock.

The U.S. Department of Agriculture has ordered raw milk testing in six states—California, Colorado, Michigan, Mississippi, Oregon, and Pennsylvania—starting December 16 to monitor the spread of H5N1 bird flu in dairy herds.
Over 720 dairy herds across 15 states have been affected by the virus since its detection in U.S. cattle in March 2024, with human cases linked to exposure remaining rare and mild.
The testing strategy aims to identify infected herds, enhance biosecurity, and provide epidemiological data to trace and contain the virus effectively.
Pasteurization has been confirmed to kill the H5N1 virus, ensuring the safety of commercial milk, while public health officials warn against consuming raw milk due to contamination risks.
At least 60 human cases of bird flu have been reported in the U.S., primarily among farm workers exposed to infected livestock, but there is no evidence of human-to-human transmission.