A extremely deadly type of avian influenza, or hen flu, has been confirmed in U.S. cattle in Texas and Kansas, the Department of Agriculture introduced on Monday.
It is the primary time that cows contaminated with the virus have been recognized.
The cows seem to have been contaminated by wild birds, and useless birds had been reported on some farms, the company stated. The outcomes had been introduced after a number of federal and state companies started investigating experiences of sick cows in Texas, Kansas and New Mexico.
In a number of instances, the virus was detected in unpasteurized samples of milk collected from sick cows. Because pasteurization kills viruses, officers emphasised that there was little threat to the nation’s milk provide.
“At this stage, there is no concern about the safety of the commercial milk supply or that this circumstance poses a risk to consumer health,” the company stated in an announcement.
Outside specialists agreed. “It has only been found in milk that is grossly abnormal,” stated Dr. Jim Lowe, a veterinarian and influenza researcher on the College of Veterinary Medicine on the University of Illinois at Urbana-Champaign.
In these instances, the milk was described as thick and syrupy, he stated, and was discarded. The company stated that dairies are required to divert or destroy milk from sick animals.
The cattle infections come on the heels of the nation’s first detection of extremely pathogenic hen flu in goats, which was introduced by Minnesota officers final week.
So far, the flu samples from sick cows haven’t contained genetic mutations which are identified to make the virus extra prone to infect people, the agriculture company stated, including that the danger to most people remained low.
“There’s still no cause to panic,” stated Stacey L. Schultz-Cherry, a virologist and influenza skilled at St. Jude Children’s Research Hospital. “It just looks like it’s another spillover event due to contact with diseased wild birds.”
Still, she famous, cows weren’t considered among the many species that had been significantly inclined to avian influenza, and the instances had been one other worrisome flip in a worldwide hen flu outbreak that has devastated wild hen populations over the previous couple of years.
The outbreak has been brought on by a brand new type of hen flu virus, referred to as H5N1, that emerged in Europe in 2020. Wild birds can unfold the virus, by means of their feces and oral secretions, to farmed poultry and different animals. Outbreaks typically flare up within the spring and summer season, when migrating birds are on the transfer.
Although avian influenza viruses are tailored to unfold primarily amongst birds, the brand new model of H5N1 has grow to be so widespread in wild birds that it has additionally repeatedly unfold to mammals, particularly scavenging species, comparable to foxes, that may feed on contaminated birds.
Infections of mammals, which give the virus new alternatives to evolve, are all the time a supply of some concern, Andrew Bowman, a molecular epidemiologist and influenza skilled at Ohio State University, stated. Scientists have lengthy been involved {that a} hen flu virus that developed to unfold extra effectively amongst mammals, together with people, may set off the following pandemic.
At this level, Dr. Bowman stated, it stays unclear whether or not the contaminated cows have all picked up the virus instantly from birds or whether or not the virus can also be spreading from cow to cow.
“That’s a question that’s going to have to get resolved quickly,” he stated. “If we have transmission cattle to cattle, that’s a different story. That certainly makes me a little more nervous.”
Additional testing and evaluation are underway. “This is a rapidly evolving situation, and U.S.D.A. and federal and state partners will continue to share additional updates as soon as information becomes available,” the company stated.
