Texas Border Business
On June 3, 2026, the U.S. Department of Agriculture (USDA) confirmed the first case of New World Screwworm (NWS) in the UnitedStates, identifying an infected calf in Zavala County, Texas. Federal and state animal health officials are actively responding to the detection by establishing an infested zone, conducting animal and fly surveillance, carrying out epidemiological investigations, and implementing established response protocols to prevent further spread.
While Zavala County is located approximately 300 miles from Cameron County, county officials have been in communication with the appropriate state and federal agencies to ensure local departments remain informed, prepared, and ready to assist response efforts while protecting animals under county care. Cameron County is also working to increase public awareness and encourage livestock owners, petowners, veterinarians, and animal caretakers to closely monitor animals for signs of infection and report any suspected cases immediately.
The confirmation follows ongoing regional coordination efforts among Rio Grande Valley county judges (Cameron, Hidalgo, Starr, and Willacy), state agencies, and animal industry partners. During a regional press conference held on May 18, 2026, local leaders discussed the potential threat posed by New World Screwworm and emphasized the importance of preparedness and public awareness.
New World Screwworm can affect livestock, wildlife, pets, and other warm-blooded animals, particularly those with open wounds or sores. While infestation in humans is rare, residents are encouraged to remain vigilant and promptly report any suspected cases.
If you suspect New World Screwworm in an animal, immediately contact the Texas Animal Health Commission at 1-800-550-8242.
Current eradication efforts rely on the release of sterile male flies, a proven method that prevents reproduction and helps eliminate screwworm populations. Currently, there are sterile flies from a reproduction facility in Panama that are being released in South Texas. Alarge-scale sterile fly production facility is also being constructed by USDA in Edinburg, Texas and is expected to be completed in November 2027.
For additional information on New World Screwworm and best practices regarding monitoring, prevention, and treatment procedures, visit the Texas Animal Health Commission’s New World Screwworm information page: https://www.tahc.texas.gov/emergency/nws.html
