Texas Agriculture Commissioner Sid Miller is urging heightened vigilance from livestock producers along the Texas-Mexico border after Mexico confirmed eight additional cases of New World screwworm in the state of Tamaulipas.

Mexico’s National Service of Agro-Alimentary Public Health, Safety, and Quality confirmed the new cases, bringing the total number of confirmed New World screwworm cases in Tamaulipas since Dec. 30, 2025, to 11. Tamaulipas borders Texas from about Laredo down to the Gulf, raising concerns about the pest’s potential spread northward.

“It’s just plain cowboy logic — when you’re seeing this many cases, this fast, it tells you there may be established screwworm fly populations in Tamaulipas,” Miller said. “We’re grateful sterile fly deployment has begun,but make no mistake: Texas producers need to stay on high alert along our border.”

According to the Texas Department of Agriculture (TDA), there is no confirmation that the affected animals had moved outside of Tamaulipas, suggesting the pest may be spreading naturally rather than through livestock movement.

“Producers should be checking livestock every day and treating any wound as a potential entry point,” Miller said. “Pay close attention to navels on young animals, isolate anything suspicious, and report concerns without delay. Early detection and aggressive surveillance are how we protect Texas livestock.”

In response to the confirmed cases, the TDA activated a comprehensive New World screwworm trapping plan along high-risk areas of the Texas–Mexico border. Traps are being placed at ports of entry, livestock export facilities and other locations where the risk of pest introduction or livestock movement is highest.

“TDA is on the ground every day with its own surveillance traps, working in lockstep with USDA and our state partners to keep a sharp eye on the border,” Miller said. “If it gets here, we will know. Now, Texas producers must stay informed and vigilant. With preparation and rapid action, we will stop the screwworm. Texas agriculture will win this fight.”

For more information on New World screwworm and how to report suspected cases, producers are directed to screwworm.gov.