Can Bird Flu Be Passed Through Milk?

Could a glass of milk on your kitchen table be tainted with bird flu (avian influenza), a potentially deadly virus? It’s a question more people are asking as dairy herds test positive for the infection.

Let’s break down what we know about the virus and milk with infectious disease specialist Lyssette Cardona, MD.

Is your milk safe?

If you’re drinking pasteurized milk, the answer is yes, your milk is safe. The pasteurization process — which involves heating raw milk at a high temperature for a short time — kills bacteria and viruses like the bird flu.

Research shows that pasteurization can quickly and completely inactivate bird flu virus in milk, reports the U.S. Food and Drug Administration (FDA).

“Pasteurization is the key because it kills the bird flu virus,” reiterates Dr. Cardona.

That’s significant, given that nearly 99% of the commercial milk supply in the United States comes from farms that follow pasteurization guidelines through the FDA’s Grade A Milk Safety Program.

FDA testing of pasteurized commercial milk products in 2024 found no evidence of the bird flu virus in various varieties of milk or dairy-based foods such as cottage cheese, sour cream and yogurt.

What about raw milk?

The bird flu virus has been found in raw milk samples from infected herds. If you drink raw (unpasteurized) milk contaminated with the bird flu virus, there’s a risk you could become infected with it.

Exposure to infected cattle and milk has led to the majority of bird flu cases reported so far in people in the U.S., according to data from the Centers for Disease Control and Prevention (CDC).

Studies have also shown that bird flu can be transmitted to mice that consume contaminated dairy milk. But there’s limited research regarding whether the bird flu virus can be passed on to people through raw milk.

Overall, the FDA considers raw milk a high-risk food given foodborne illness outbreaks linked to its consumption. The FDA warns that raw milk can expose you to dangerous bacteria such as:

• E. coli
• Salmonella
• Listeria
• Brucellosis

“There’s a potential risk that comes from consuming raw milk — and it goes beyond bird flu,” notes Dr. Cardona. “It’s just safer in general to stay with pasteurized products.”

That includes buying dairy-based products such as various soft cheeses, yogurts and ice creams. Choosing dairy products with “pasteurized milk” in the ingredients list is your safest option.

Is raw milk being tested?

The U.S. Department of Agriculture (USDA) launched a National Milk Testing Strategy at the end of 2024 to track infections in herds. The goal is to better understand — and hopefully halt — the spread of the virus.

As of the end of 2024, there had been confirmed cases of bird flu in 915 livestock herds in 16 states. It’s believed that dairy cows get the virus through contact with infected birds.

Who is at high risk for bird flu?

The CDC considers the general public health risk for bird flu to be low, whether it’s through food or other sources. Worldwide, human infection with bird flu viruses has been labeled “limited and sporadic.”

Risk levels increase if you work with or are around animals infected with the virus. (Examples would include people on dairy or poultry farms where bird flu has been found.)

Given the spread of the virus among birds and animals, the CDC says it “would not be surprising” to see more cases of people with bird flu. However, it remains categorized as primarily an animal health issue.

Still, the World Health Organization (WHO) has documented nearly 1,000 cases of bird flu in people globally between 2003 and 2024. Nearly half of the cases led to death. (Most cases in the U.S. in 2024 resulted in just mild illnesses.)

Dr. Cardona offers these tips to stay safe:

• Use pasteurized milk and pasteurized milk products
• Thoroughly cook eggs, poultry and beef before eating, as heat kills the bird flu virus and other bacteria
• Wash your hands thoroughly after preparing meals with eggs or raw meat
• Avoid contact with dead birds or animals
• Wash your hands regularly if you’re around animals in settings such as a farm or animal market

“Bird flu is very low risk to most of us at the moment,” Dr. Cardona states, “but it’s always good to be careful where you can.”