USDA Orders Raw Milk Samples to Be Tested for Bird Flu

Bottles of raw milk are displayed for sale at a store in Temecula, Calif., on May 8, 2024. JoNel Aleccia/AP, file

The U.S. Department of Agriculture (USDA) has ordered that dairy farmers work with the federal agency to test raw milk for the bird flu (H5N1).

“This new milk testing strategy will build on those steps to date and will provide a roadmap for states to protect the health of their dairy herds,” USDA Secretary Tom Vilsack said in a statement on Friday.

“Among many outcomes, this will give farmers and farmworkers better confidence in the safety of their animals and ability to protect themselves, and it will put us on a path to quickly controlling and stopping the virus’ spread nationwide.”

The USDA’s National Milk Testing Strategy (NMTS) requires that unpasteurized milk samples be collected and tested at USDA laboratories “to better inform biosecurity containment measures, as well as to inform state-led efforts to reduce risk to farm workers who may be in contact with animals infected with H5N1.”

The USDA said bird flu was first identified in dairy cattle in March 2024, prompting an order to test cattle for the virus before interstate travel.

This tactic has helped to reduce the spread to other states, the USDA said.

Still, more measures are needed to “contain and eliminate” the infection in livestock, the USDA said, after cases of the virus were detected in raw milk.

“USDA has precedent with successful bulk milk testing approaches, including the use of bulk milk testing to eradicate brucellosis from dairy herds,” the federal department said in an October statement on milk testing. “In addition, Colorado implemented statewide bulk milk testing after H5N1 was detected in dairy herds in two counties, and the most recent statewide testing has not detected any evidence of H5N1 in any herds in the state.”

The USDA is working with private and state veterinarians toward implementing the first round of tests on a local and farm level “until herds in an area are determined to be free of the virus.”

“USDA continues to emphasize to farmers nationwide that biosecurity is the best weapon against the spread of H5N1, and farms should practice good biosecurity even if the virus has not been detected in their state or vicinity,” the USDA said. “Data collected over the past seven months has shown that H5N1 can be transmitted on equipment, people, or other items that move from farm to farm, including between dairies and poultry facilities.”

The USDA encouraged herd owners to participate in the Animal and Plant Health Inspection Service (APHIS) producer support program that offers up to $1,500 for farm biosecurity development.

The NMTS federal order issued on Friday requires that raw milk samples “from any entity responsible for dairy farm, bulk milk transporter, bulk milk transfer station, or dairy processing facility” share those samples with the USDA.

It also requires that herd owners with cattle that have tested positive for bird flu “provide epidemiological information that enables activities such as contact tracing and disease surveillance.”

“Finally, like USDA’s April 24 Federal Order, it requires that private laboratories and state veterinarians report positive results to USDA that come from tests done on raw milk samples drawn as part of the NMTS,” the USDA said.

The first round of testing will begin the week of Dec. 16.

The USDA added that the new order doesn’t replace the April order requiring mandatory dairy cow testing but complements it.

There will be five stages in the testing: plant silo monitoring, determining state results, responding to the virus in affected states, reporting the absence of the virus in unaffected states, and “demonstrating freedom from H5 in U.S. Dairy Cattle,” the USDA said.

“This testing strategy is a critical part of our ongoing efforts to protect the health and safety of individuals and communities nationwide,” said U.S. Health and Human Services Secretary Xavier Becerra.