Note: Our May 3 blog post shared a map of past and current wild bird outbreaks and language that was confusing. We have removed that map and updated the information. 

What is H5N1 and why is it in the news?

H5N1 is a kind of bird flu virus that is common in wild birds around the world. (H5N1 may also be referred to as HPAI – Highly Pathogenic Avian Influenza – which is a group of bird flu viruses). Over the past few years, H5N1 virus has also caused outbreaks in commercial poultry operations. 

Recently, H5N1 has been in the news because the virus has been detected in dairy cows in several states in the U.S.  One worker in Texas sickened by H5N1. (Previously, one person was sickened in 2022.)

So far, there have been no reports of the H5N1 virus in Oregon dairy cows. 

The Centers for Disease Control (CDC) and the US Department of Agriculture (USDA) are leading the response to H5N1 virus outbreaks in dairy cows. The CDC’s risk assessment for the general public is low. No person-to-person spread of the H5N1 virus has been detected. This is one of the things the CDC is monitoring. 

What are the recommendations for people who are around livestock?

Specific recommendations for farmers; poultry, backyard flock, and livestock owners; and worker protection are available.

According to the CDC, people should avoid unprotected exposures to sick or dead animals including wild birds, poultry, other domesticated birds, and other wild or domesticated animals (including cattle), as well as with animal carcasses, raw milk, feces (poop), litter, or materials contaminated by birds or other animals with confirmed or suspected H5N1 virus infection. 

People exposed to birds or other animals with confirmed or suspected H5N1 virus infection should be monitored for any signs and symptoms of illness for 10 days after the last known exposure, including people wearing recommended personal protective equipment (PPE). Additional information on protective actions around birds, including what to do if you find a dead bird, is available on CDC’s website.

What about drinking milk and eating dairy products?

The U.S. Food and Drug Administration (FDA) is not concerned with the safety of the commercial milk supply at this time. Only milk from healthy animals is authorized for distribution into interstate commerce for human consumption. Additionally, pasteurization is required for any milk entering interstate commerce. Pasteurization has been proven to inactivate bacteria and viruses, like influenza, in milk. Milk from ill (symptomatic) animals is being diverted or destroyed so that it does not enter the human food supply.

Additionally, the FDA has been testing products in the national commercial milk supply, including milk, cottage cheese and baby formula. Results find that pasteurization is effective in inactivating H5N1.  

What about raw milk and cheeses?

People should not prepare or eat uncooked or undercooked food or related uncooked food products, such as unpasteurized (raw) milk, or products made from raw milk such as cheeses, from animals with confirmed or suspected H5N1 infection. 

FDA’s longstanding position is that unpasteurized, raw milk can harbor dangerous microorganisms that can pose serious health risks to consumers, and FDA is reminding consumers of the risks associated with raw milk consumption in light of the H5N1 detections.

What’s next?

CDC continues to work with USDA, FDA, and state health departments to monitor people exposed to animals infected with the H5N1 virus. Because influenza viruses constantly change, continued surveillance and preparedness efforts are critical, and CDC is taking measures in case the public health risk assessment changes. This is a developing situation, and CDC will share additional updates as new relevant information becomes available.

Stay up to date with the CDC at https://www.cdc.gov/flu/avianflu/avian-flu-summary.htm.