USDA Declares Minnesota Dairy Herds Unaffected by Bird Flu
The U.S. Department of Agriculture (USDA) has confirmed that Minnesota’s dairy herds are currently free from active cases of the H5N1 bird flu virus, after months of monitoring showed no new infections.
This declaration shifts Minnesota into the “Unaffected” category under the USDA’s National Milk Testing Strategy (NMTS), a program launched in 2024 to monitor raw milk for traces of H5N1. The change means Minnesota’s Department of Agriculture (MDA) and Board of Animal Health can now reduce testing frequency from monthly to every two months, though continued surveillance remains in place.
Background: Minnesota’s Bird Flu Case
The state first detected H5N1 in a dairy herd in March 2025, marking the first such case in Minnesota since June of the previous year. That single incident prompted the state to ramp up testing, with officials sampling raw milk across herds to contain the virus.
No additional cases have been detected since, clearing the way for USDA to restore the state’s unaffected designation.
Why This Matters for Dairy Farmers
For dairy producers, the USDA’s update has both practical and economic significance:
Reduced Testing Burden – Fewer milk sample submissions saves time and resources for farmers while maintaining public health safeguards.
Continued Restrictions – Despite the status change, federal rules still restrict the movement of dairy cattle across state lines, as a precaution against spread.
Market Confidence – The “unaffected” label helps bolster consumer and trade confidence in Minnesota’s dairy sector, a cornerstone of the state’s agricultural economy.
Ongoing Risk and National Monitoring
While Minnesota’s status has improved, the broader picture remains mixed. According to USDA data:
Affected States – Texas, Arizona, California, Nevada, and Idaho still have herds listed as “Affected” by H5N1.
Provisional Unaffected States – Wisconsin and Iowa remain under “Provisional Unaffected,” meaning herds are still undergoing surveillance before full clearance can be granted.
National Goal – USDA will continue monitoring until all 50 states are listed as “Unaffected.”
If new cases appear, USDA case managers work directly with farms to implement biosecurity measures, quarantine affected animals, and conduct follow-up testing.
The Bigger Picture: H5N1 and Dairy Cattle
Traditionally known as a disease of wild birds and poultry, the highly pathogenic avian influenza virus (HPAI H5N1) has increasingly been detected in non-avian species, including dairy cattle, cats, and even humans in isolated cases.
While pasteurization kills the virus in milk, raw milk can carry risk, which is why surveillance of bulk tank samples has been central to USDA’s strategy. The agency emphasizes that the commercial milk supply remains safe due to mandatory pasteurization standards.
Minnesota’s Agricultural Outlook
Minnesota is the seventh-largest dairy producer in the U.S., home to more than 400,000 dairy cows and over 2,000 dairy farms. The USDA’s confirmation of “unaffected” status is not only a public health milestone but also an economic relief for producers concerned about trade disruptions and consumer confidence.
“Keeping our herds healthy is critical to protecting farmers’ livelihoods and ensuring safe food for consumers,” the Minnesota Department of Agriculture said in a statement following the USDA’s update.
Looking Ahead
For now, Minnesota dairy farmers can breathe easier, but experts warn that continued vigilance is essential. The seasonal migration of wild birds, which are the main carriers of H5N1, will remain a concern. Enhanced biosecurity measures—from limiting farm visitors to monitoring herd health closely—will remain part of the state’s prevention strategy.
As the USDA continues tracking the virus nationwide, Minnesota’s “unaffected” status serves as an example of how strict monitoring and rapid response can help protect livestock, safeguard rural communities, and stabilize a vital agricultural industry.
