U.S. halts livestock imports from Mexico amid screwworm outbreak

The United States Department of Agriculture (USDA) has announced an immediate suspension of live cattle, horse, and bison imports from Mexico through southern border ports.

This decision comes in response to the rapid spread of new world screwworm (NWS) in Mexico, with recent detections as far north as Oaxaca and Veracruz, approximately 700 miles from the U.S. border.

Despite ongoing collaborative efforts between the United States and Mexico to control and eradicate NWS, the pest’s northward progression has necessitated stricter measures. Effective immediately, the USDA’s Animal and Plant Health Inspection Service (APHIS), in partnership with Customs and Border Protection (CBP), will enforce this import ban on live animals from Mexico. The suspension will be reviewed monthly until significant containment is achieved.

U.S. Secretary of Agriculture Brook Rollins emphasized the urgency of the situation.

“Protecting our livestock industry and ensuring the safety of our nation’s food supply is a top priority. This suspension is a necessary step to prevent the further spread of this devastating pest,” explained Rollins.

The USDA’s strategy for eradication includes robust field surveillance, controlled animal movement, and the release of sterile insects. The agency is also deploying USDA Tick Riders to monitor livestock and wildlife along the southern border for signs of NWS.

The NWS, a parasitic fly whose larvae can cause severe damage to animals, was first detected in Mexico in November 2024. The USDA had previously closed the border to live animal trade following this detection but reopened it in February 2025 after implementing stringent inspection and treatment protocols. However, the pest has continued to spread northward, prompting the current import suspension.

For more information on the affected regions and trade restrictions, click here.