An outbreak of bird flu among U.S. dairy cows has affected more than two dozen dairy herds in eight states, just weeks after the nation’s largest egg producer discovered the virus in its chickens.

Health officials stressed that the risk to the public is low and that the U.S. food supply remains safe and stable.

“At this time, there remain no concerns that this situation poses a risk to consumer health or the safety of the interstate commercial milk supply,” the FDA said in a statement.

Here’s what you need to know about bird flu and food:

Which states have found bird flu in dairy cows?

As of Friday, the avian flu virus that has killed millions of wild birds in recent years has been found in at least 26 dairy herds in eight U.S. states: Idaho, Kansas, Michigan, New Mexico, North Carolina, Ohio, Texas and the South. Dakota.

The virus, known as type A H5N1, has been identified in a range of mammals over the past few years, but this is the first time it has been found in cattle, according to federal health and animal agencies. The Centers for Disease Control and Prevention said genetic analysis of the virus does not indicate it has changed to spread more easily among people.

How does avian influenza affect food production?

Agriculture officials in at least 17 states have restricted the import of cows from states where the virus has been detected, but government agencies say so far it has had little impact on commercial milk production. Officials believe the cows may have become infected through contact with wild birds but said “the possibility of transmission between cows cannot be ruled out”.

Farmers are testing cows showing symptoms of the infection, including a sharp decrease in milk production and lethargy. Animals showing signs of illness or testing positive will be separated from other animals on the farm. The animals seemed to recover within two weeks.

U.S. egg producers are monitoring the situation closely after bird flu was discovered in chickens in Texas and Michigan. Millions of birds have been killed, but the FDA says the risk of affected eggs entering the retail market or causing human infection is low because of federal inspections and other safeguards.

Can pasteurization kill bird flu?

Scientists say there is no evidence that people can catch the virus by eating food that has been pasteurized, heat-treated or cooked correctly.

“This is not a food safety issue,” said Lee-Ann Jaykus, an emeritus food microbiologist and virologist at North Carolina State University.

So far, two people in the United States have been infected with bird flu. A Texas dairy worker recently recovered from a mild eye infection after close contact with an infected cow. In 2022, a prison inmate in a work program contracted the virus when he killed infected birds at a poultry farm in Colorado. His only symptom was fatigue, from which he recovered.

Can grocery store milk protect against bird flu?

Food safety experts and government officials say yes.

U.S. producers are prohibited from selling milk from sick cows and must move and destroy the milk. Additionally, milk sold across state lines needs to be pasteurized or heat treated to kill bacteria and viruses (including influenza viruses).

“We firmly believe that pasteurization provides a safe milk supply,” Tracey Forfa, director of the FDA’s Center for Veterinary Medicine, told an audience during a webinar this week.

Can raw milk prevent bird flu?

The FDA and CDC are less certain about unpasteurized or raw milk sold in many states, saying there is limited information about the possible spread of the H5N1 virus in such products.

So far, no herds with links to raw milk suppliers have reported cows infected with avian influenza, but the agencies advise the industry not to produce or sell raw milk or raw milk cheese made with milk from cows showing symptoms. products, or exposure to cows infected with avian influenza. dairy cow.

U.S. health officials have long warned about the risk of foodborne illness associated with raw milk, which the Centers for Disease Control and Prevention said was responsible for more than 200 outbreaks between 1998 and 2018, sickening more than 2,600 people.

Still, raw milk proponents such as Mark McAfee, owner of American Raw Milk Farms in Fresno, Calif., say outbreaks of the H5N1 virus among commercial dairy cows appear to have spurred product sales despite federal warnings. increase.

Can you get bird flu from eating eggs or meat?

So far, only dairy cows have been infected or shown signs of illness, and no beef cattle have been infected, agriculture officials said.

The largest U.S. egg producer temporarily halted operations on April 2 after bird flu was found in its chickens. After the tests, Cal-Maine Foods culled about 1.6 million laying hens and another 337,000 pullets, or young hens.

The company said there is no risk to eggs on the market and no eggs have been recalled.

Barbara Kowalcik, director of the Center for Food Safety and Nutrition Security at George Washington University, said eggs that are handled properly and cooked thoroughly are safe to eat.

“A lot of people like runny eggs. Personally, if I eat an egg, it’s cooked well,” she said.

Still, Kowalczyk and others warn that things could change.

“This is an emerging issue and obviously this pathogen is evolving and there’s a lot we don’t know,” she said. “I do think everyone is trying to get this resolved as quickly as possible.”