Officials confirm New World screwworm cases and expand federal response

What This is

• New World screwworm larvae, a flesh-eating parasite that infests wounds, have been confirmed in Texas animals, triggering an expanded federal and state eradication response.
• USDA confirmed two additional Texas detections—a calf in La Salle County and a dog in Andrews County—bringing the total to four confirmed Texas infections reported in these summaries.
• Officials have set quarantines and movement-control zones, expanded trapping and surveillance (including wildlife monitoring), and urged animal owners and veterinarians to inspect wounds and promptly report suspicious larvae.
• The core eradication tactic is releasing sterile male screwworm flies to break reproduction, a method used in earlier U.S. campaigns against the pest.
• USDA is scaling up sterile-fly supply by increasing production, converting a site in Mexico, and planning a large Texas facility, with some reports describing the Texas plant as not fully operational until at least 2027.
• Texas Gov. Greg Abbott activated state resources and pushed to accelerate construction of the Texas sterile-fly breeding facility to strengthen containment capacity.
• Trade and animal-movement restrictions have expanded, including U.S. limits on livestock imports from Mexico and a temporary Canadian ban on livestock that were in Texas within the prior 21 days.
• Officials have emphasized the outbreak is primarily an animal-health and production issue and say it is not a food-safety concern, while noting the parasite can rarely affect humans.

Why This Matters

• A wider outbreak could sharply raise costs and losses for ranchers and related rural businesses, especially where cattle inventories are already tight.
• Containment decisions can reshape North American livestock trade flows, shifting where animals are fed and processed and who captures jobs and value added.
• The response tests government capacity to fund and scale biosecurity tools quickly, including large specialized production facilities with long lead times.
• How authorities balance caution against disruption will influence public trust in animal-disease controls and cross-border coordination.