USDA Drops H5N1 Tests for Interstate Dairy Cattle From Unaffected States

The U.S. Department of Agriculture has narrowed a federal testing requirement for dairy cattle moving between states, exempting herds in states that have formally demonstrated they are free of H5N1 through the National Milk Testing Strategy.

The Animal and Plant Health Inspection Service said the change takes effect immediately. Lactating dairy cattle from states holding “Unaffected State Status” no longer need a negative pre-movement test before crossing state lines. The exemption does not apply simply because a farm has reported no illness: a state must maintain the federal surveillance and testing needed to confirm that status.

That distinction matters for both disease control and cattle logistics. The April 2024 federal order introduced testing before interstate movement after highly pathogenic avian influenza H5N1 was detected in U.S. dairy cattle. USDA is now replacing a universal requirement with a risk-based one for qualifying states, while leaving the broader surveillance framework in place.

For dairy operators and livestock haulers in unaffected states, the immediate consequence is fewer tests and less administrative friction when moving lactating cows. States without the designation remain subject to the pre-movement requirement, so the practical effect will vary with each state’s surveillance status rather than creating a nationwide end to testing.

USDA said the revision follows an October 2025 resolution from the United States Animal Health Association. The agency also said it does not expect the change to affect trade in cattle, beef or dairy products. That is an important limit on the announcement: it changes a domestic movement protocol, not U.S. export access or the safety rules governing commercial milk.

The agency continues to require affected milk to be diverted or destroyed and notes that pasteurization inactivates the virus. The Centers for Disease Control and Prevention continues to assess the risk to the general public as low, while people with occupational exposure to infected animals face a more direct risk and remain a focus of health guidance.

The policy therefore represents a targeted easing, not a declaration that the dairy outbreak is over. APHIS said its eradication strategy and biosecurity recommendations remain unchanged, and producers should continue reporting cattle with reduced feed intake, falling milk production, abnormal milk or other clinical signs consistent with infection.

The next operational question is how many states sustain unaffected status as surveillance continues. A state that cannot demonstrate the required absence of infection would not receive the exemption, preserving testing as a control at the point where cattle movements could otherwise carry disease across state lines.