This week, state and federal officials said it’s likely that wild migratory birds gave a deadly type of bird flu to dairy cows in Texas and Kansas.
High-pathogenic avian influenza (HPAI) virus was found in cows in the US for what is thought to be the first time. Last week, officials in Minnesota reported that an HPAI case had been found in a young goat. This is the first time that the virus has been found in a domestic ruminant in the US.
According to the Associated Press, the Texas Animal Health Commission revealed that the flu virus is Type A H5N1, which has been killing birds all over the world for several years. The virus’s rapid and ongoing spread has caused many cases of spillover into mammals. This makes epidemiologists worry that the virus could change and spread widely in people.
The public is not at high risk right now. The US Department of Agriculture (USDA) said that genetic testing by the National Veterinary Services Laboratories showed that the H5N1 strain that spread to the cows doesn’t seem to have any changes that would make it easier for people to get. The flu type was found in some milk samples from cows that were infected, but the USDA made it clear that all milk from animals that were infected is being sent somewhere else and thrown away. Dairy farms must only send milk from animals that are safe to be processed so that people can drink it. Still, even if some milk that was contaminated with flu was made safe for people to drink, the normal process of pasteurization kills germs and viruses, including flu.
So far, the virus seems to be mostly affecting older cows, according to the government. Three farms in Kansas, one in Texas, and milk from sick cows all had the virus. It was also found in a throat swab from a cow on a second farm in Texas. The USDA said that farmers have found dead birds on their land, which means they were exposed to birds that were sick. It has also been said that cows in New Mexico are sick. Cows that have the bird flu seem to have less milk output and a loss of appetite.
So far, though, the USDA doesn’t think that the spread of H5N1 will have a big effect on milk production or the herds. There hasn’t been much milk loss; the infection has only been seen in about 10% of infected herds, and there has been “little to no associated mortality.” The USDA said it would stay alert and called the infections a “rapidly evolving situation.”
Federal and state officials are still keeping an eye on the virus, but Texas officials want to reassure people. “The public is not in danger, and there will be no shortages,” said Sid Miller, the commissioner of agriculture for Texas. “It is known that no contaminated milk got into the food chain; it was all thrown away.” What if some milk with the virus gets into the food chain? The pasteurization method will kill the virus.