Colorado dairy farm worker contracts bird flu as 23 livestock herds quarantined

(The Center Square) – A Colorado dairy worker tests positive for bird flu as 23 livestock herds in the state are under quarantine, according to state and federal agencies.

The U.S. Department of Agriculture reported 54 herds were infected with Highly Pathogenic Avian Influenza (HPAI) during the last 30 days. The Colorado Department of Agriculture reported a total of 27 confirmed cases since late April.

The Centers for Disease Control and Prevention on Wednesday announced confirmation of a human case of infection of HPAI in a Colorado dairy worker. The CDC reported two previous cases of human infection in Michigan and one in Texas.

“As with previous cases, the person is a worker on a dairy farm where cows tested positive for A(H5N1) virus,” the CDC reported. “The person reported eye symptoms only, received oseltamivir treatment, and has recovered. CDC has been watching influenza surveillance systems closely, particularly in affected states, and there has been no sign of unusual influenza activity in people, including in syndromic surveillance.”

The U.S. Food and Drug Administration's website stated bird flu viruses normally don't infect humans, but sporadic infections have happened.

"It is important to note that 'highly pathogenic' refers to severe impact in birds, not necessarily in humans," according to the FDA site.

The disease is highly contagious and often deadly in poultry, according to the F.D.A. The viruses, H5 and H7, can be transmitted by wild birds to domestic poultry and other birds and animals.

In April, the U.S.D.A. ordered all dairy cattle be tested for the virus before interstate movement. Colorado’s dairy industry reported cash receipts for dairy products at $1.3 billion in 2022.

Colorado reported 23 dairy herds under quarantine between June 10 and July 1. The state agriculture department in April announced it would implement federal guidelines to prevent the spread of the disease.

The U.S.D.A.’s Animal and Plant Health Inspection Service reported the first infection of the disease in the nation’s poultry flock in 2022. The federal agency reported infections in 11 poultry flocks in Minnesota and Iowa during the last 30 days.

Since the livestock outbreak started earlier this year, it affected 140 herds in 12 states – Idaho, Wyoming, Colorado, New Mexico, Texas, South Dakota, Kansas, Minnesota, Iowa, Michigan, Ohio and North Carolina.

“Although bird flu viruses do not normally infect humans, sporadic human infections have occurred,” according to the FDA. “It is important to note that ‘highly pathogenic’ refers to severe impact in birds, not necessarily in humans.”

The FDA published a report last week to confirm that pasteurization is effective in inactivating the virus in milk and other dairy products made from pasteurized milk. The CDC also recommends avoiding unpasteurized or “raw” milk.

“The results from this and previous studies are clear about the safety of the commercial milk supply,” according to the FDA report .