Californians Urged to Avoid Raw Milk Amid Bird Flu Outbreak on Dairy Farms

Raw milk can carry dangerous bacteria at any time. But as bird flu continues to circulate in cow herds across the U.S., federal regulators and health experts are cautioning California’s raw milk producers and consumers that the risks from drinking unpasteurized milk are heading in one direction: up.

Despite the warnings, raw milk continues to be produced and sold in the state’s grocers, and the California Department of Food and Agriculture told KQED its sale remains legal, which officials allow so long as producers can show a “continual and highly diligent attention to cleanliness and hygiene at both the farm and the bottling plant.”

Unlike pasteurized milk, raw milk does not undergo a heating process that is meant to kill or inactivate harmful bacteria and viruses. Researchers do not yet know how the virus may be transmitted to humans, and scientists like UC Davis’ Essam Abdelfattah are concerned that people who drink raw milk could get sick. “Any human being drinking raw milk is putting themselves at higher risk for diseases,” Abdelfattah said.

With California allowing the sale of raw milk, regulators are putting consumers at a higher risk of exposure to multiple diseases, not only bacterial diseases but also avian influenza, he said. Abdelfattah is a veterinary scientist.

The U.S. Department of Agriculture detected the first cases of bird flu, or H5N1, in dairy cattle on March 25 in Texas and Kansas. Since then, the USDA has detected dozens of herds positive for the virus in 9 states.

While none of these cases were in California, scientists recommend erring on the side of caution.

“Like many infectious agents, there is no magic wall between states,” said Peter Chin-Hong, infectious disease physician at UCSF.

That means that the possibility of the virus reaching California shouldn’t be ruled out. “Personally, for me and my family members, people I care about, and my patients, I’ll tell them to lay off raw milk right now,” Chin-Hong said.

Although scientists agree that the likelihood of human transmissions from cows is currently low, that could change in the next few months. “The ground zero of avian flu is not the cow; it’s the bird. And birds fly from state to state with wild abandon,” Chin-Hong said.

So far, there have been two reported human cases of bird flu in the U.S., one following an exposure to poultry in 2022 and one, more recently, in a person who interacted with infected dairy cows in Texas.

Debate over drinking raw milk

The Food and Drug Administration bans the interstate sale of raw milk and has long cautioned people against drinking it because of the risk of foodborne diseases; guidance that the agency is now reiterating because of the spread of bird flu. The agency asked that the industry stop manufacturing or selling raw milk products from cows showing symptoms or that were exposed to the virus. The Centers for Disease Control and Prevention also warns people that drinking raw milk can lead to serious illness.

Last month, the FDA reported that 1 in 5 pasteurized milk products nationwide tested positive for the H5N1 virus. Pasteurized milk appears to still be safe to consume because the process makes the virus inactive. Nevertheless, experts believe that the significant viral load might suggest that the virus is spreading at a higher rate than previously known.

Industry groups and producers of raw milk have pushed back, calling the warnings against raw milk related to avian flu “fear-mongering.” Mark McAfee, the CEO and founder of Raw Farm, a dairy farm in Fresno and one of the largest raw milk producers in the country, said the sale of his company’s product “has never been higher.”

“Farmers have figured out how to produce raw milk at a very low risk,” he said. He argues there are ways to produce raw milk that are clean and safe to drink. This includes sourcing milk from a single farm and ensuring that the milking equipment is clean.

Bonni Gilley, a Fresno resident, has been drinking raw milk for more than 20 years and said it hasn’t made her sick. The recent warning left her undeterred. “Raw means raw, like out of the lady, out of the cow,” she said. “To me, it’s more wholesome. I always look for products that are as close to being directly off the vine as possible.”

But Chin-Hong thinks continuing raw milk consumption, given the rapidly evolving nature of the virus, is “like playing Russian roulette.”

“The risk of infection isn’t the same for everyone,” Chin-Hong said.

When it comes to potential infection, he is most concerned about elderly people, young children, immunocompromised and pregnant individuals. “It’s often more challenging to treat these individuals just because their immune system isn’t quite as developed or robust. And the ability of drugs to work depends on some help from the immune system,” he said.

Health officials have been stockpiling vaccines and adjuvants and are ready to manufacture more if needed. Doctors can currently choose from four antiviral options and administer them to those suspected of H5N1 infections.

There is currently no requirement to test raw milk for H5N1. The FDA and USDA said they are working on testing retail milk and dairy samples for H5N1.

Those who choose to continue to drink raw milk should be extra cautious, Chin-Hong said. He recommends that people look out for any symptoms, such as headache, muscle aches, difficulty breathing, diarrhea, or vomiting, and contact their healthcare provider. “Because the earlier someone can get ahead of it, the better,” he said.

Slowing the spread of bird flu

Jaydee Hanson, policy director at the Center for Food Safety, a nonprofit that advocates for food and agricultural issues, said too much attention has been given to drinking or not drinking milk. The bigger issue is containing the potential spread of the virus.

For weeks, the USDA has required H5N1 PCR or genetic testing for all dairy cattle before they are moved between states. But Hanson thinks that rule is not strict enough.

“The USDA and the FDA need to be banning any shipment of animals from farms that are known to have the bird flu to other operations, whether in the state or out of state,” he said. “We don’t want this virus to mutate and act in mammals the way it does in poultry. The FDA and the USDA need to get their act together.”

Avian flu can be transmitted from birds to other animals through direct contact, such as with saliva, mucus, and feces of infected animals, or through another animal, like pigs.

Pigs are known to be susceptible to both avian and human influenza viruses. They theoretically could act as an intermediate host, or a go-between, of the new kind of infection, passing on a hybrid mutation of the virus to a person.

If this hybrid virus survives in humans, it can be easily transmitted to other humans. Something similar happened in 2009 with another avian influenza virus, H1N1, which killed over 200,000 people worldwide.

While the risk to the general public remains low, UC Davis’s Abdelfattah said people who work on farms and have regular contact with infected animals should be extra cautious because they are at higher risk of infection. “We need to care about the safety of these workers because these people are on the front line,” he said.

Some of the precautions include wearing personal protective equipment such as gloves and masks while handling sick animals. California health officials told KQED that they will support a one-time distribution of respirators, gloves, safety goggles and other protective equipment to workers at dairy and poultry farms, as well as slaughterhouses, as these businesses scramble to protect against bird flu.