The USDA has launched a bold screwworm response plan to prevent the return of the New World screwworm to the United States. The parasite, recently detected in southern Mexico, poses a serious threat to U.S. livestock and food production.
1. New Facility Will Release Sterile Flies
A major part of the plan involves building a sterile fly dispersal facility in Hidalgo County, Texas. The USDA will invest $8.5 million in the site, which will become operational by late 2025. It will release millions of sterile male flies to interrupt the screwworm’s breeding cycle. This method was used successfully in the 1960s to eliminate the parasite from the U.S.
Texas lawmakers, including Rep. Tony Gonzales and Sen. John Cornyn, have supported the project as a proactive move to protect farmers and ranchers.
2. Import Restrictions and Border Surveillance
To prevent new cases from entering the country, the USDA has temporarily banned imports of live cattle, horses, and bison from Mexico. The agency will reassess the restriction monthly.
The screwworm response plan also includes tighter border surveillance. Officials are increasing animal inspections, setting up traps, and working closely with veterinarians in both countries to track outbreaks.
Related Blog: Suspension of Mexican Cattle Imports: Update
3. International Collaboration and Fly Production
Alongside its U.S. efforts, the USDA will contribute $21 million to upgrade a sterile fly facility in Metapa, Mexico. This site, along with Panama’s fly production center, will supply sterile flies to stop the screwworm’s spread across Central America and northern Mexico.
The U.S. and Mexico are also coordinating on surveillance, data sharing, and livestock monitoring to strengthen the response on both sides of the border.
4. Emergency Readiness at Home
Federal and state agencies are preparing emergency action plans in case screwworm is detected in the U.S. Animal health teams are training for rapid response, stockpiling treatment supplies, and running drills to ensure quick containment.
Why the Screwworm Response Plan Matters
If left unchecked, a screwworm outbreak could devastate the U.S. cattle industry. It would cost billions in losses and drive up food prices. The USDA’s screwworm response plan uses proven science and global collaboration to stop the parasite before it takes hold again.
Sources
Polansek, T. (2025, June 18). USDA plans sterile fly facility in Texas to combat screwworm. Reuters. https://www.reuters.com/world/us/usda-plans-sterile-fly-facility-texas-combat-screwworm-2025-06-18/
Associated Press. (2025, June 18). The US plans to open a fly factory in Texas as part of its fight against a flesh-eating parasite. AP News. https://apnews.com/article/5eb62edc42bcfce40cdbea27b5f8b60c
Laredo Morning Times. (2025, June 18). U.S. halts live cattle, horse, bison imports from Mexico over screwworm outbreak. https://www.lmtonline.com/news/article/us-mexico-livestock-import-ban-screwworm-20322881.php
