There has been a recent disease event in dairy cattle with reports of affected herds in several states.
Samples submitted from dairy cattle affected with the current disease outbreak were recently confirmed by the U.S. Department of Agriculture to have highly pathogenic avian influenza, according to the American Association of Bovine Practitioners. It is too soon to predict if all of the recent reports of unexplained illnesses in dairy cattle in the United States are due to HPAI. Veterinarians and the dairy industry are working collaboratively with state and federal officials during the ongoing investigation.
H5N1 in birds, mammals
HPAI is most commonly found in birds and poultry; wild waterfowl are known carriers. According to the USDA, 48 states have had cases of HPAI in poultry and wild birds since the outbreak began in 2022. More than 82 million birds have been affected. There have also been reports of over 200 mammals diagnosed with the virus.
The cases in dairy cattle are unique as it is only the second time it has been found in a U.S. ruminant (cattle, sheep, goats). Earlier this month, HPAI was found in goats in Minnesota on a farm where poultry first tested positive. According to the USDA, migratory birds appear to be the source of the infection in cattle.
Impact on dairy cattle
Veterinarians and animal caregivers first reported seeing decreased feed intake and milk production in affected dairy cattle. Dairies are reporting that about 10% of the milking cows become sick. There have been no confirmed deaths in cattle due to this disease. Cattle appear to recover in two-to-three weeks with supportive care.
Food safety
Federal and state guidelines exist to ensure the safety of milk and meat products. Milk that is pasteurized and meat that is properly cooked remains safe for human consumption.
AABP will continue to monitor this situation and provide reliable information to its members and the public. For more information, see the USDA announcement at https://www.aphis.usda.gov/aphis/newsroom/news/sa_by_date/sa-2024/hpai-cattle
