Editor’s note: Updated with CDC confirmation of human HPAI cases in Texas.
U.S. animal health officials say they cannot rule out cow-to-cow transmission of highly pathogenic avian influenza (HPAI) after avian influenza was detected in dairy herds in three other states. ing.
The U.S. Department of Agriculture’s National Veterinary Services Laboratory (NVSL) confirmed the presence of HPAI in a Michigan dairy herd that recently received cattle from a Texas farm. The department said it had received “presumptive positive test results” in additional herds in New Mexico, Idaho and Texas, after it was confirmed in two herds in Texas and two in Kansas early last week.
“The spread of symptoms in Michigan’s herds also indicates that HPAI transmission among cattle cannot be ruled out,” the Department of Agriculture, Food and Drug Administration, and Centers for Disease Control and Prevention (CDC) wrote on March 29. This is stated in the joint statement issued.
The CDC announced on April 1 that a person in Texas who came into contact with one of the infected herds tested positive for the HPAI virus, and the main symptom was red eyes. People who have had close or prolonged contact with infected animals are at higher risk of infection, but the CDC says the risk to the general public is still low.
According to an April 1 update from Alberta Milk Co. and a subsequent emailed statement from the Canadian Food Inspection Agency, HPAI has not been detected in dairy cows in Canada so far.
“CFIA has not detected HPAI in dairy cows or other livestock in Canada,” a CFIA spokesperson told RealAgriculture. “We are monitoring the situation closely.”
Alberta Milk says new developments mean biosecurity measures need to be strengthened on Canadian dairy farms, and Canadian dairy farmers are working with the Canadian Food Inspection Agency and other experts to , noted that they are collaborating on specific Canadian recommendations to strengthen vigilance and biosecurity on Canadian farms. .
One of the symptoms in U.S. herds is reduced milk production, but affected animals have recovered after isolation and few associated deaths have been reported, the U.S. federal agency said.
U.S. officials said early tests showed no changes in the virus that would make it more contagious to humans. The virus found in Michigan is very similar to the wild bird strain (H5N1, Eurasian goose/Cantonese clade 2.3.4.4b) identified in Texas and Kansas.
USDA also advises veterinarians and producers to practice proper biosecurity, test animals before required movement, minimize movement of animals, and isolate sick cattle from the herd. are doing.
When it comes to food safety, authorities say dairy manufacturers must divert milk from sick animals and all products are pasteurized, inactivating bacteria and viruses such as influenza. says there are no concerns about commercial milk supplies.
