Officials warn of risks to people with possible exposure amid bird flu outbreak in cows

The Biden administration said Wednesday it’s working to strengthen federal testing guidance and the overall public health response should the bird flu outbreak in cows spread among humans.

State health labs have sent “around 25” human test samples to the CDC for reference testing amid the current dairy outbreak, according to officials. And more than 100 workers are being monitored. Officials declined to answer questions from reporters about where in the country the monitored workers are, saying only that officials are “following the herd” of infected cows.

“The risk here of something going from one or two sporadic cases to becoming something of international concern, it’s not insignificant,” CDC Principal Deputy Director Nirav Shah said at a Council on Foreign Relations event on Wednesday. “We’ve all seen how a virus can spread around the globe before public health has even had a chance to get its shoes on. That’s a risk and one that we have to be mindful of.”

Federal officials said agencies are working to raise “broad awareness” about current risks to humans, which remain “low” amid the outbreak among cows and birds. “But there are certain groups of people who are at greater risk of infection who should take precautions,” said Demetre Daskalakis, director of the CDC’s National Center for Immunization and Respiratory Diseases.

Those groups include dairy farmers and workers, especially amid concerns that the virus is spreading asymptomatically among cows.

But huge challenges remain to testing people, including farmworkers who’ve had contact with infected cattle.

And the federal testing regime so far has lagged after the virus among dairy cows was identified more than a month ago and was likely spreading for months prior.

Daskalakis said CDC syndromic surveillance — which tracks symptoms observed in patients across the country — has not found any unusual flu trends or activity suggesting that avian flu has spread to humans. One person has been confirmed to contract avian flu in the current outbreak: a Texas dairy worker who showed symptoms of conjunctivitis, or pink eye, and has since recovered.

The CDC has put out interim recommendations for people at risk of exposure, including farm and slaughterhouse workers, as well as recommendations for state and local health officials on how to prevent exposure and spot symptoms.

There are two vaccine candidates in development to reduce the risk of avian flu in humans, officials said, with one of the vaccines in clinical trials. However, there are no immediate plans to roll out vaccines widely, officials said.

The outbreak: Wild birds infecting Texas dairy herds are believed to be the initial source of infection. Interstate movement of the cows has since spread the virus among 36 known cattle herds in nine states.

Biden administration officials are rushing to ensure the outbreak doesn’t turn into another human health pandemic, while also trying to limit the economic blow to the U.S. dairy sector following the detection of inactive bird flu particles in the nation’s pasteurized milk supply.

Federal officials also said Wednesday the FDA has conducted further testing on 201 milk samples that initially tested positive for bird flu particles, including in pasteurized retail dairy products like cottage cheese and sour cream. The FDA hasn’t found any new live virus fragments, officials said, reaffirming its assessment that the pasteurized U.S. milk supply is safe. One caveat: Officials reiterated their previous warnings about the risks of drinking raw milk, especially in the current environment.

The USDA has tested at least 2,000 potentially infected cattle and expects to see an increase in testing as it implements a federal order that requires testing dairy cattle prior to their interstate transport.

Federal challenges: USDA has told state officials that “while it is still unclear exactly how virus is spreading, the virus is shed in milk at high concentrations.”

Last Friday, the FDA said it hasn’t found any live virus in a limited batch of the milk samples that initially tested positive for bird flu particles.

But concerns are growing beyond the dairy industry about the potential risks to beef products.

USDA announced Tuesday it will start sampling a small amount of ground beef sold at retail stores in the nine states where officials have detected bird flu in dairy herds. Officials and the beef industry have said they believe the beef supply remains safe, especially if consumers cook the meat to the recommended internal temperature.

Concerns about the safety of U.S. beef supplies could quickly present trade complications. Colombia has already limited the imports of U.S. beef, citing the spread of avian flu in dairy herds. But trade groups like the National Cattlemen’s Beef Association chalked up the move to politics, noting that the U.S. does not currently allow imports of Colombian beef.

USDA officials sought to reassure trading partners, noting the department’s “robust surveillance system” for animal disease that helps maintain a safe food supply for “domestic and international markets,” spokesperson Allan Rodriguez said in a statement.