Dairy cows infected with highly pathogenic avian influenza A, or H5N1, in five U.S. states have died or been slaughtered by farmers because they did not recover, according to state officials and academics.
In South Dakota, a dairy farm with 1,700 cows sent a dozen animals to slaughter after they did not recover from the virus and killed another dozen that contracted secondary infections, said Russ Daly, a professor at South Dakota State University and a veterinarian for the state extension office who spoke with the farm.
“You get sick cows from one disease, then that creates a domino effect for other things, like routine pneumonia and digestive issues,” Mr. Daly said.
A farm in Michigan culled about 10 percent of its 200 infected cows after they failed to recover from the influenza, also known as bird flu, according to Phil Durst, an educator with Michigan State University Extension who spoke with that farm.
In Colorado, some dairies reported culling cows with the bird flu because they did not return to milk production, said Olga Robak, spokesperson for the state Department of Agriculture. Cows infected with the influenza typically display symptoms such as reduced milk production and lethargy.
Ohio Department of Agriculture spokesperson Meghan Harshbarger said infected cows have died in Ohio and other affected states, mostly due to secondary infections.
The Texas Animal Health Commission also confirmed that cows have died from secondary infections at some dairy operations with avian flu outbreaks.
Officials could not provide figures for the number of statewide cow mortalities.
New Mexico’s state veterinarian, Samantha Uhrig, said farmers increasingly culled cows due to decreased milk production early in the outbreak, even before the United States confirmed that bird flu was infecting cattle. Culling decreased as farmers learned that most cows gradually recovered, she said.
Officials in North Carolina and Kansas said there have been few to no cow deaths associated with bird flu in their states. Idaho officials did not respond to requests for information.
The bird flu jumped from poultry to cattle in the United States in late 2023 or early 2024, according to government scientists. Cases have been confirmed in three people as well as 84 dairy herds across 11 states, according to federal and state officials. The three human patients have all recovered, although the majority of patients reported to the World Health Organization since 2003 have died.
Authorities in Mexico reported on June 5 that a man with serious underlying conditions, including chronic kidney disease, who had contracted H5N2—a strain similar to that circulating in the United States—died in April.
Officials in Iowa and Minnesota confirmed cases for the first time this week in cattle.
“No cows in Iowa have been depopulated,” Don McDowell, director of communications for the Iowa Department of Agriculture and Land Stewardship, told The Epoch Times in an email.
Officials in Minnesota did not respond to a request for comment.
A U.S. Department of Agriculture (USDA) spokesperson said the agency knew of a few deaths in cows but that the vast majority of the cattle recovered.
The USDA has in briefings and press releases said that cows infected with the avian influenza “generally recover well, and there is little mortality associated with the disease.”
As part of the response to the bird flu, the USDA tested samples from cows sent to be culled. Testing found particles of the bird flu in tissue from one of 96 cows, the agency said previously.
Government personnel at the slaughterhouse “identified signs of illness in the positive animal during post-mortem inspection and prevented the animal from entering the food supply,” the USDA said. It said the meat did not enter the food supply, which should “provide further confidence that the food safety system we have in place is working.”
USDA scientists injected ground beef patties with a surrogate virus and found that cooking the burgers to at least 145 degrees Fahrenheit (medium) rendered the virus undetectable. However, the virus was still detectable in burgers cooked to 120 degrees Fahrenheit (rare).
Scientists both inside and outside the government are still trying to figure out how the virus is spreading among cows. Both bird-to-cow and cow-to-cow transmission are happening, according to the USDA, but it’s unclear how the virus is being spread.
Person-to-person transmission has not yet been seen, the U.S. Centers for Disease Control and Prevention says. The agency deems the risk to the public as low.
Reuters contributed to this report.
From The Epoch Times