USDA: Second strain of bird flu detected in cattle for the first time

Feb. 6 (UPI) -- A second strain of bird flu has been detected in U.S. dairy cattle, marking the first confirmed infections of this particular virus in cows, the U.S. Department of Agriculture said.

The USDA said the strain of highly pathogenic avian influenza is genotype D1.1 and it was detected in dairy cattle in Nevada.

The infections were found during the USDA's Milk Testing Strategy in the state and confirmed Jan. 31.

"This is the first detection of this virus genotype in dairy cattle," the USDA said in a statement. "Genotype D1.1 represents the predominant genotype in the North American flyways this past fall and winter and has been identified in wild birds, mammals and spillovers into domestic poultry."

At least 957 U.S. dairy herds have tested positive for bird flu since the first infection was detected in March 2024. There have been 36 new confirmed cases among cattle in the last 30 days, the majority detected in California and a handful in Nevada.

Sixty-four human cases of the disease have been confirmed amid the outbreak, according to the U.S. Centers for Disease Control and Prevention, with a death reported in early January in Louisiana.

Bird flu has also greatly affected poultry.

In the last few months, tens of millions of birds have been affected by the outbreak, and nearly 154 million since the outbreak among poultry was detected in February 2022.

Officials have blamed the infections among poultry for the national shortage eggs and the surging cost of the kitchen staple. According to the U.S. Bureau of Labor Statistics, a dozen eggs in November, when President Donald Trump was elected, cost $3.65, compared to $4.15 the next month.

The USDA said that despite confirmation of the first D1.1 strain among cattle, it does not change its strategy for detecting the avian flu.

"USDA APHIS continues to work with the Nevada Department of Agriculture by conducting additional on-farm investigations, testing and gathering additional epidemiological information to better understand this detection and limit further disease spread," it said.