There’s been an ongoing outbreak of bird flu in dairy cows since March 2024. The pasteurization process ensures that milk is safe to drink by killing the virus. However, raw milk may still contain bird flu.

There are many different types, subtypes, and lineages of influenza (flu) virus. Avian influenza, or bird flu, is a type of flu virus that mainly affects birds. It can be either highly pathogenic (HPAI) or low pathogenic (LPAI).

In March 2024, HPAI was reported in dairy cows in several states, marking the first time this type of flu virus has been found in cows. Shortly afterward, scientists detected the virus in samples of raw, unpasteurized milk.

You may be wondering whether the milk that you buy from the store is safe to consume. The answer is yes.

What is highly pathogenic avian influenza?

Highly pathogenic avian influenza, or HPAI, is a type of bird flu that causes a severe, and often fatal, illness in birds.

Like other influenza A viruses, bird flu is characterized by two proteins found on its surface: hemagglutinin (HA) and neuraminidase (NA). In birds, there are 16 different types of HA and nine different types of NA.

HPAI viruses have one of two HA types, 5 or 7, and are called H5 and H7 viruses. While many H5 and H7 viruses are low pathogenic (LPAI), meaning they cause milder illness, viruses like H5N1, H5N8, and H7N9 are all HPAI.

H5N1 is the HPAI virus that was found in dairy cows.

It’s highly unlikely that you can catch bird flu from milk. Pasteurization is a big reason for this.

Pasteurization is the process through which raw milk or other milk-based products are heated to kill any germs that are in them, such as viruses and bacteria.

It involves heating milk to a high temperature, often 161°F (72°C), for at least 15 seconds before cooling it back down.

What does the research say?

In a May 2024 study of bird flu virus in cow’s milk, scientists used lab equipment to heat milk samples to 161°F for 15 seconds. They found that this significantly reduced the amount of virus in the sample but didn’t completely inactivate it.

Another June 2024 study supported these findings. It reported a very significant drop in the amount of virus in milk after 5 seconds at 161°F.

However, there was still a very small amount of active virus at 20 seconds.

While these results are informative, they don’t reflect real-world conditions. The scientists in both studies stressed that they cannot replicate the commercial pasteurization process using their lab equipment.

That’s where a July 2024 study comes in. Researchers in this study analyzed a total of 297 samples of grade A pasteurized milk products. Samples included 132 milk processors from 38 states.

The scientists detected the virus’s genetic material in 20.2% of the samples. However, infectious virus was not found. That means that pasteurization was effective at killing bird flu virus in milk.

The bottom line: It’s safe to consume commercially available milk products. That’s because the pasteurization process can effectively kill bird flu virus and other germs present in milk.

How is bird flu passed from cows to people?

According to the Centers for Disease Control and Prevention (CDC), there have been a total of 58 cases of bird flu in people in 2024 as of December 2024.

Of these, 31 of them were associated with exposure to cows. No person-to-person spread of bird flu has been reported.

The people who have contracted bird flu from cows have been workers on dairy or cattle farms. They got the virus through having close contact with cows, not by drinking milk.

The commercial milk supply remains safe, according to the Food and Drug Administration (FDA). That’s because 99% of commercially available milk in the United States is pasteurized before entering the market, the organization says.

There still may be a risk of getting sick if you consume raw, unpasteurized milk. For example, the May 2024 study above found that mice became ill after consuming raw milk samples containing bird flu.

According to the FDA, there’s limited research on whether bird flu can be transmitted to humans through raw milk products.

However, the CDC recommends against consuming raw milk in general. That’s because consuming raw milk products can expose you to other harmful germs, such as:

While pasteurization can kill the bird flu virus in milk, further measures are in place to help prevent human illness.

The CDC, FDA, and U.S. Department of Agriculture (USDA) continue to track and monitor the spread of bird flu in cows.

According to the USDA, milk from cows known to be sick with bird flu is being diverted out of the commercial milk supply and destroyed.

The best way to prevent getting ill from drinking dairy milk containing the bird flu virus is to only drink pasteurized milk.

Pretty much all milk in the United States that’s available to consumers is pasteurized. However, if you’re ever unsure, follow the tips below.

  • Check the label: Labels on milk products will note that the product is pasteurized. If you don’t see “pasteurized” on a product label, it’s possible that it may contain raw milk.
  • Ask a clerk: A grocery clerk may be able to tell you whether a product in their store is pasteurized.
  • Use caution at farmers’ markets: Don’t purchase milk products from farmers’ markets or roadside stands unless you can confirm that they’ve been pasteurized.

You may also be wondering if the flu vaccine can protect you from bird flu. The answer is no.

While the flu vaccine is safe and effective for preventing serious illness from the seasonal flu, it cannot protect against bird flu. Bird flu viruses are quite different from the flu strains included in the seasonal flu vaccine.

The overall risk to the general public from bird flu is low. The vast majority of the people who have contracted bird flu have had close contact with sick cows or birds.

If you’ve been exposed to an animal, either alive or dead, that may have had bird flu, contact your doctor if you have symptoms like:

Be sure to let them know that you had close contact with an animal that may have been sick with bird flu.

Consuming raw milk products can lead to illness in general, especially food poisoning. Contact a doctor if you’ve consumed raw milk and are having symptoms like:

What states have the bird flu in milk?

A total of 15 states have had confirmed bird flu in dairy cows since March 2024. These are California, Utah, Idaho, Wyoming, Colorado, New Mexico, Texas, Oklahoma, Kansas, South Dakota, Minnesota, Iowa, Michigan, Ohio, and North Carolina.

Is it safe to drink dairy milk?

Yes, it’s safe to drink commercially available dairy milk. Pasteurization kills bird flu and other germs in the milk. Milk from sick cows is being removed from the commercial supply and destroyed.

What kills avian flu virus?

Pasteurization can kill bird flu virus in milk. Similar to seasonal flu virus, cleaning and disinfecting can kill virus on surfaces, while handwashing can help to remove virus from your hands.

Since March 2024, there’s been an ongoing bird flu outbreak in dairy cows. Bird flu has also been detected in milk from these cows.

Despite this, it’s still safe to drink commercially available milk. This is because the pasteurization process kills bird flu virus in the milk.