A highly lethal type of bird flu has been confirmed in cattle within the US in Texas and Kansas, – announced the Department of Agriculture on Monday.
Cows infected with the virus have been identified for the primary time.
The agency said the cows were almost certainly infected by wild birds, and cases of birds dying were reported on some farms. The results were announced after multiple federal and state agencies began investigating reports of sick cows in Texas, Kansas and New Mexico.
In several cases, the virus was detected in unpasteurized milk samples taken from sick cows. Because pasteurization kills viruses, officials stressed there’s little risk to the nation’s milk supply.
“At this stage, there are no concerns about the safety of the commercial milk supply or that this circumstance poses a health risk to consumers,” the agency said in a press release.
Outside experts agreed. “It has only been detected in milk, which is grossly abnormal,” said Dr. Jim Lowe, a veterinarian and influenza researcher on the College of Veterinary Medicine on the University of Illinois at Urbana-Champaign.
In such cases, the milk was described as thick and syrupy and was then thrown away. The agency said dairies have an obligation to divert or destroy milk from sick animals.
The cattle infections occurred immediately after the country’s first detection of highly pathogenic bird flu in goats, which took place announced by Minnesota officials last week.
So far, flu samples from sick cows haven’t contained genetic mutations known to make humans more likely to be infected with the virus, the agriculture agency said, adding that the danger to most of the people stays low.
“There’s still no need to panic,” said Stacey L. Schultz-Cherry, a virologist and flu expert at St. Paul’s Children’s Research Hospital. Jude. “This appears to be another side effect caused by exposure to sick wild birds.”
However, she noted that cows weren’t considered a species particularly susceptible to bird flu, and the cases were one other worrying turn in the worldwide bird flu epidemic that has devastated wild bird populations over the past few years.
The outbreak was attributable to a brand new type of the bird flu virus, often called H5N1, that emerged in Europe in 2020. Wild birds can spread the virus through feces and oral secretions to farmed poultry and other animals. Outbreaks often break out in spring and summer when migrating birds are on the move.
Although bird flu viruses are adapted to spread mainly amongst birds, the brand new H5N1 version has change into so widespread amongst wild birds that it has also repeatedly spread to mammals, especially scavenger species akin to foxes that may prey on infected birds.
Mammalian infections that give the virus recent opportunities to evolve are at all times of some concern, said Andrew Bowman, a molecular epidemiologist and flu expert at Ohio State University. Scientists have long feared that the bird flu virus, which has evolved to spread more efficiently amongst mammals including humans, could cause one other pandemic.
Dr. Bowman said it’s currently unclear whether the entire infected cows contracted the virus directly from the birds or whether the virus also spreads from cow to cow.
“This is an issue that needs to be resolved quickly,” he said. “If it’s cattle-to-cattle transmission, that’s a different story. It definitely makes me a little more nervous.”
Additional testing and evaluation is ongoing. “The situation is rapidly evolving, and USDA and federal and state partners will continue to provide additional updates as information becomes available,” the agency said.
