USDA requires additional testing for avian flu in dairy herds

The United States Department of Agriculture implemented new testing requirements for dairy herds on April 24, as an avian flu outbreak continues to spread in herds across the nation.

Under the new requirements, prior to interstate transfers dairy cows will be required to receive a negative test for influenza A and contact tracing for positive animals will be instituted.

The first positive test for avian flu in a dairy herd came in late March in Texas and cases have since been confirmed in eight states, with the most recent coming in Idaho on April 19.

A press release from the United States Department of Agriculture (USDA) announcing the new requirements said that the agency had identified disease transmission between cows in the same herd, from cows to poultry and between dairies owing to cow movements, as well as cows that tested positive while asymptomatic.

The release said that the new testing requirements would help USDA officials form a better understanding of the movement of the avian flu between wild birds and cows and help to lower the risk of further interstate spread.

So far, there have been no mutations in the virus that would increase its transmissibility to people, though cases among those in direct contact with infected animals are possible. The USDA release said that the officials at the Centers for Disease Control believed the risk to the public remains low and noted that infected cows are recovering after receiving care.

The release also stressed that milk from impacted cows was diverted or destroyed and that pasteurization has proven to inactivate viruses in milk.