An outbreak of bird flu in U.S. dairy cows has grown to affect more than two dozen herds in eight states, just weeks after the nation's largest egg producer discovered the virus in its chickens.
Health authorities emphasize that the risk to the population is low and that the food supply remains stable and safe in the United States.
“At this time, there is no concern that this circumstance represents a risk to consumer health, or that it affects the safety of the interstate commercial milk supply,” the United States Food and Drug Administration (FDA) detailed in a statement. for its acronym in English).
Here's what you need to know about bird flu and food:
Which states have detected bird flu in dairy cows?
As of Friday, the strain of bird flu that has killed millions of wild birds in recent years has been detected in at least 26 dairy herds in eight U.S. states: Idaho, Kansas, Michigan, New Mexico, North Carolina, Ohio , Texas and South Dakota.
The virus, known as Type A H5N1, has been found in a number of mammals in recent years, but it is the first time it has been discovered in livestock, according to federal law enforcement and animal agencies. A genetic analysis of the virus does not show that it has changed to spread more easily between people, the US Centers for Disease Control and Prevention (CDC) said.
How does bird flu affect food production?
Agricultural authorities in at least 17 states have restricted imports of dairy cattle from states where the virus has been detected, but so far government agencies indicate it has had little effect on commercial milk production.
Officials believe the cows likely became infected from exposure to wild birds, but spread between cows “cannot be ruled out.”
Farmers test cows that show symptoms of infection, including lethargy and a large decrease in milk production. Animals showing symptoms or testing positive for the disease are being isolated from other animals on farms. The animals seem to recover after two weeks.
Egg producers in the United States are watching the situation closely after bird flu was detected in chickens in Texas and Michigan. Millions of birds have been euthanized, but the FDA says the risk of infected eggs reaching the retail market or causing infections in humans is low because of federal inspections and other safeguards.
Does pasteurization kill bird flu?
Scientists note that there is no evidence to indicate that people can contract the virus from eating foods that have been pasteurized, heat-treated or properly cooked.
“It's not a food health concern,” said Lee-Ann Jaykus, a food microbiologist and virologist emeritus at North Carolina State University.
To date, two people in the United States have been infected with bird flu. A Texas dairy worker who was in close contact with an infected cow recently had a mild eye infection and has since recovered.
In 2022, an inmate participating in a work program contracted it while slaughtering infected birds at a poultry farm in Colorado. Her only symptom was fatigue and she recovered.
Is supermarket milk safe against bird flu?
Yes, according to food safety experts and government officials.
U.S. producers are prohibited from selling milk from sick cows and must divert and destroy it. Additionally, milk sold across state lines must be pasteurized or heat-treated using a process that kills bacteria and viruses, including influenza.
“We strongly believe that pasteurization provides a safe milk supply,” Tracey Forfa, director of the FDA's Center for Veterinary Medicine, said in a webinar this week.
Is raw milk safe against bird flu?
The FDA and CDC are less sure about unpasteurized, or raw, milk sold in many states, as there is little information about possible transmission of the H5N1 virus in such products.
So far, no herds linked to raw milk suppliers have reported cows infected with bird flu, but the agencies recommend that the industry not produce or sell raw milk products or raw milk cheeses made with milk from cows that are showing symptoms or are exposed to infected cows.
U.S. health officials have long warned about the risk of foodborne illness linked to raw milk, which the CDC says caused more than 200 outbreaks that sickened more than 2,600 people between 1998 and 2018.
Still, raw milk advocates like Mark McAfee, owner of Raw Farm USA in Fresno, California, say the H5N1 outbreak in commercial cows appears to have propped up sales of the products, despite warnings from the federal government.
Can you get bird flu by eating eggs or meat?
To date, only dairy cows, not cattle, have been infected or are showing signs of illness, according to agricultural officials.
The largest egg producer in the United States temporarily suspended operations on April 2 after discovering bird flu in its chickens. Cal-Maine Foods euthanized about 1.6 million laying hens and another 337,000 young hens after the discovery.
The company asserted that eggs on the market were not at risk and that there have been no egg recalls.
It's safe to eat eggs that are handled properly and cooked well, said Barbara Kowalcyk, director of the Center for Food Safety and Nutritional Security at George Washington University.
“Many people like eggs with runny yolks. Personally, if I eat an egg, it is very well cooked,” she commented.
Still, Kowalcyk and others have warned that the situation may change.
“This is an emerging issue and clearly this pathogen is evolving, and there are many things we don't know,” he said. “I do think everyone is trying to figure it out as quickly as possible.”
Connect with the Voice of America! Subscribe to our channels Youtube, WhatsApp and to newsletter. Turn on notifications and follow us on Facebook, x and instagram.
