AUSTIN — Texas Agriculture Commissioner Sid Miller has urged livestock producers to step up vigilance along the Texas–Mexico border after Mexico confirmed eight additional cases of New World screwworm (NWS) in the border state of Tamaulipas.
The detections were confirmed by Mexico’s National Service of Agro-Alimentary Public Health, Safety, and Quality (SENASICA) and raise the total number of confirmed cases in Tamaulipas to 11, intensifying concerns that the pest could be establishing itself in areas close to major US livestock production zones.
New World screwworm is a parasitic fly whose larvae infest living tissue, creating painful and rapidly worsening wounds in animals. The condition can become fatal if left untreated, posing a serious threat to cattle, sheep, goats and other livestock. While the pest has historically been controlled through coordinated surveillance and sterile insect deployment programmes, the latest rise in confirmed cases has triggered heightened monitoring efforts on the US side of the border.
“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,” Commissioner 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.”
Texas officials said the Texas Department of Agriculture (TDA) has not received confirmation that the affected animals reported by SENASICA had moved outside Tamaulipas. That lack of movement history has raised concerns that the pest may be spreading naturally, rather than being introduced through livestock transport.
TDA said it is working closely with the US Department of Agriculture (USDA) and animal health partners to strengthen early detection and prevent potential spread into Texas. The agency is urging producers—particularly those operating near the border—to take preventive action immediately and treat any signs of infection as urgent.
“Producers should be checking livestock every day and treating any wound as a potential entry point,” Commissioner 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.”
The warning comes as livestock operators face mounting pressure to manage animal health risks alongside rising operating costs and continued market volatility. For producers in border regions, the threat of NWS adds another layer of operational challenge, with the potential for disruption if surveillance measures lead to movement restrictions or increased inspection requirements.
Although no confirmed cases have been reported in Texas in the update, the proximity of Tamaulipas to key livestock routes and commercial operations has sharpened focus on biosecurity and rapid reporting. Industry specialists typically advise producers to inspect animals frequently for unusual wounds, particularly around branding sites, castration areas, ear tags and navels in newborn livestock, where infestation risk can be higher.
Expanded TDA Surveillance and Trapping Efforts
In response to the latest developments, TDA has activated a comprehensive NWS trapping plan aimed at bolstering early detection across high-risk areas along the Texas–Mexico border.
The effort includes strategic trap placement at:
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Ports of entry
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Livestock export facilities
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Other locations where pest introduction or livestock movement risk is highest
TDA inspectors will monitor the traps regularly, with samples rapidly assessed in partnership with federal agencies to ensure fast identification and response. The approach is designed to provide early warning and allow for swift containment should the pest be detected in Texas.
“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,” Commissioner 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.”
Texas is one of the largest livestock-producing states in the United States, and any spread of NWS could carry wider implications for animal welfare, farm profitability and supply chain continuity. Officials are therefore emphasising the importance of early detection, strict wound management, and immediate reporting of suspicious cases as the most effective measures to protect herds and prevent escalation.
For now, state officials are positioning surveillance and producer awareness as the first line of defence, while continuing to coordinate with federal partners and monitor developments in northern Mexico.
