Mexico’s National Service of Agro-Alimentary Public Health and Safety has detected 11 cases of New World screwworm in Tamaulipas state bordering Texas since Dec. 30, according to the Texas Department of Agriculture.
“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,” said TDA Commissioner Sid Miller, who noted eight of the cases are new. “We’re grateful sterile fly deployment has begun but make no mistake, Texas producers need to stay on high alert along our border.”
However, the Texas Department of Agriculture has not received confirmation that the affected animals reported by the Mexican agency have a history of movement outside Tamaulipas, raising concerns that the pest may now be spreading naturally rather than being introduced through animal movement.
New World screwworm infestation occurs when screwworm fly larvae infest the tissue or flesh of warmblooded animals and people, according to the U.S. Center for Disease Control. Screwworm flies are attracted to and lay eggs on and in open wounds. It does not regularly occur or spread in the United States. The parasite is typically found in South America and the Caribbean, although Mexico and countries in Central America are reporting cases in animals and people. If you travel to areas where the flies are present, have an open wound, spend time among livestock animals, or sleep outdoors, you may be at greater risk of becoming infested with New World screwworm.
TDA says it continues to work closely with the U.S. Department of Agriculture and animal health partners and urges Texas producers, especially those along the border, to take preventive action now.
“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.”
TDA has activated a comprehensive NWS trapping plan to bolster early detection across highrisk areas along the Texas–Mexico border. The effort includes strategic trap placement at ports of entry, livestock export facilities and other locations where pest introduction or livestock movement is highest.
TDA inspectors monitor traps regularly, with samples rapidly assessed in partnership with federal agencies to ensure fast identification and response, according to the agency.
“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 response efforts, visit www.screwworm. gov.
