Bird Flu Spreads to Dairy Cows

A type of avian influenza that has been extremely deadly in birds has been confirmed in U.S. dairy cattle in Texas and Kansas, the Division of Agriculture introduced on Monday.

It’s the first time that cows contaminated with the virus have been recognized.

The cows seem to have been contaminated by wild birds, and useless birds have been reported on some farms, the company mentioned. The outcomes have been introduced after a number of federal and state companies started investigating stories of sick cows in Texas, Kansas and New Mexico.

The sickness has primarily affected older cows, inflicting signs that embrace decreased urge for food, fever and a sudden drop in milk manufacturing. To this point, the usD.A. mentioned, there had been few or no stories of deaths within the affected herds.

In a number of instances, the virus was detected in unpasteurized samples of milk collected from sick cows. Pasteurization ought to inactivate the flu virus, specialists mentioned, and officers confused that the milk provide was protected.

“At this stage, there isn’t a concern in regards to the security of the industrial milk provide or that this circumstance poses a danger to client well being,” the company mentioned in a press release.

Outdoors specialists agreed. “It has solely been present in milk that’s grossly irregular,” mentioned Dr. Jim Lowe, a veterinarian and influenza researcher on the School of Veterinary Medication on the College of Illinois at Urbana-Champaign.

In these instances, the milk was described as thick and syrupy, he mentioned, and was discarded. The company mentioned 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 chicken flu in goats, which was introduced by Minnesota officers final week.

To this point, the flu samples from sick cows haven’t contained genetic mutations which might be recognized to make the virus extra prone to infect people, the agriculture company mentioned, including that the chance to most of the people remained low.

“There’s nonetheless no trigger to panic,” mentioned Stacey L. Schultz-Cherry, a virologist and influenza knowledgeable at St. Jude Kids’s Analysis Hospital. “It simply seems to be prefer it’s one other spillover occasion attributable to contact with diseased wild birds.”

Nonetheless, she famous, cows weren’t regarded as among the many species that have been significantly vulnerable to avian influenza, and the instances have been one other worrisome flip in a world chicken flu outbreak that has devastated wild chicken populations over the previous couple of years.

The outbreak has been brought on by a brand new type of chicken flu virus, often known as H5N1, that emerged in Europe in 2020. Wild birds can unfold the virus, by their feces and oral secretions, to farmed poultry and different animals. Outbreaks usually flare up within the spring and summer season, when migrating birds are on the transfer.

Though avian influenza viruses are tailored to unfold primarily amongst birds, the brand new model of H5N1 has change into so widespread in wild birds that it has additionally repeatedly unfold to mammals, particularly scavenging species, resembling foxes, which 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 knowledgeable at Ohio State College, mentioned. Scientists have lengthy been involved {that a} chicken flu virus that developed to unfold extra effectively amongst mammals, together with people, may set off the following pandemic.

At this level, Dr. Bowman mentioned, it stays unclear whether or not the contaminated cows have all picked up the virus immediately from birds or whether or not the virus can also be spreading from cow to cow.

“That’s a query that’s going to must get resolved shortly,” he mentioned. “If we have now transmission cattle to cattle, that’s a distinct story. That actually makes me somewhat extra nervous.”

Extra testing and evaluation are underway. “It is a quickly evolving scenario, and U.S.D.A. and federal and state companions will proceed to share further updates as quickly as info turns into out there,” the company mentioned.