USDA supports producers with resources and financial aid.

In partnership with State veterinarians, USDA is implementing a National Milk Testing Strategy that facilitates comprehensive H5N1 surveillance of the Nation’s milk supply and dairy herds. The strategy is designed to increase our understanding of the virus’ spread in the United States; support the rapid implementation of enhanced biosecurity measures to decrease the risk of transmission to other livestock; and inform critical efforts to protect farmworkers to help lower their risk of exposure.

This new strategy builds on measures we have taken since the beginning of the avian influenza outbreak to contain the virus. This includes those taken by States and national risk mitigation measures like USDA's April 2024 Federal Order, which requires testing before cattle movement between States and has helped limit the spread of H5N1 to new States.

Biosecurity is the best weapon against the spread of H5N1. Data shows that the virus can be transmitted on equipment, people, or other items that move from farm to farm, including between dairies and poultry facilities. 

USDA continues to emphasize to farmers nationwide the importance of practicing good biosecurity, even if the virus has not been detected in their State or vicinity. We offer financial assistance to herd owners for planning and implementing enhanced biosecurity practices.  

With each detection of HPAI in livestock, USDA and our Federal and State partners have taken swift action to trace animal movements, assess the disease prevalence in herds, and initiate a variety of testing activities to confirm the safety of the meat and milk supplies.

While the current public health risk is low, CDC, in partnership with USDA and other Federal agencies, is also watching the situation carefully and working with States to monitor people with animal exposures. Learn more about CDC’s flu surveillance systems and HPAI activity in people.

In addition, USDA has implemented or expanded a number of programs to support affected dairy premises. For example, our voluntary Dairy Herd Status Program offers dairy producers the option to monitor their herds via weekly bulk milk samples before moving them across State lines, without having to test each individual animal. We currently have 100 herds across 18 States enrolled in this program. 

We continue to support the rapid development and timely approval of an H5N1 vaccine for dairy cows, in addition to other species. Several vaccine candidates for use in dairy cows are currently undergoing field trials.  

USDA has consistently operated on a science-based, step-by-step approach informed by what we learn about this virus through our everyday work, research, and monitoring efforts, and this marks the next step in the escalation of our response. 

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Understanding how HPAI spreads is critical to mitigate risk, contain the virus, and strengthen prevention. 

After HPAI H5N1 was first confirmed on a dairy premises in March 2024, USDA immediately worked with States to conduct additional testing for HPAI, as well as viral genome sequencing, to learn how it was spreading among dairy cattle. USDA and State teams conducted extensive epidemiological work to investigate the links between HPAI-affected dairy premises and evidence of spillover into poultry premises.

Continued disease transmission regionally within the country is due to several factors. In addition to the movement of livestock, transmission between farms is likely related to normal business operations such as numerous people, vehicles, and other farm equipment frequently moving on and off an affected premises and on to other premises. Importantly, it is not currently believed that the disease is spread onto dairy or poultry premises by migratory waterfowl—this is supported by both genomic and epidemiological data analysis.