From September, the United States Department of Agriculture (USDA) will begin testing dairy cows at meat factories for the presence of bird flu. It will test muscle samples from dairy cow carcases under its national residue programme.

The samples will be tested for polymerase chain reaction (PCR) testing and carcases will be held at the factory pending the results of the testing.

In the event of a carcase testing positive for bird flu, the USDA said it will “work with industry to ensure the carcase does not enter the food supply.”

Some 191 cases of bird flu have been reported in dairy cows across 13 US states since March. The USDA said the testing is a cautionary measure to “gain more information about the avian influenza in slaughtered animals and protect from the virus spreading more in dairy cattle.”

Since April 2024, 13 human cases of bird flu virus have been reported in the US.