By Mike Stobbe and Jonel Aleccia
Adapted for radio by S. Baxter Clinton
(AP) Milk from dairy cows in Texas and Kansas has tested positive for bird flu, U.S. officials said Monday March 25th.
Officials with the Texas Animal Health Commission confirmed the flu virus is the Type A H5N1 strain, known for decades to cause outbreaks in birds and to occasionally infect people. The virus is affecting older dairy cows in those states and in New Mexico, causing decreased lactation and low appetite.
It comes a week after officials in Minnesota announced that goats on a farm where there had been an outbreak of bird flu among poultry were diagnosed with the virus. It's believed to be the first time bird flu — also known as highly pathogenic avian influenza — was found in U.S. livestock.
The commercial milk supply is safe and risk to people is low, according to the U.S. Department of Agriculture. Dairies are required to only allow milk from healthy animals to enter the food supply, and milk from the sick animals is being diverted or destroyed. Pasteurization also kills viruses and other bacteria, and the process is required for milk sold through interstate commerce, the agency said.
The USDA said in a statement, “At this stage, there is no concern about the safety of the commercial milk supply or that this circumstance poses a risk to consumer health.”
The federal government said its tests in the cattle did not detect any changes to the virus that would make it spread more easily to people.
Dairy farmers in Texas first became concerned three weeks ago when cattle started falling ill with what officials called “mystery dairy cow disease," Texas Department of Agriculture Commissioner Sid Miller said. Milk production fell sharply and the cows were lethargic and weren't eating much.
Miller said, “We hadn't seen anything like it before. It was kind of like they had a cold.”
The state's animal health commission began an investigation that included tests for bird flu, spokeswoman Erin Robinson said. Based on findings from Texas, USDA officials think the cows got the virus from infected wild birds.
Experts say livestock appear to recover on their own within seven to 10 days. That's different than bird flu outbreaks in poultry, which necessitate killing flocks to get rid of the virus. Since 2022, outbreaks have led to the loss of about 80 million birds in U.S. commercial flocks.
So far, the virus appears to be infecting about 10% of lactating dairy cows in the affected herds, said Michael Payne, a food animal veterinarian and and biosecurity expert with the University of California-Davis Western Institute for Food Safety and Security.
Payne said, “This doesn’t look anything like the high-path influenza in bird flocks.”
