EL PASO, Texas — The flesh-eating New World screwworm has turned up in the El Paso area for the first time, and state animal health officials have placed much of eastern and southern El Paso County inside a quarantine zone.
A veterinarian found the parasite Oct. 27 in a dog in Socorro, according to the Texas Animal Health Commission. The dog spent time outdoors but had not been near cattle. Days earlier, on Oct. 23, two cows at separate rural sites in Hudspeth County tested positive, and New Mexico officials confirmed cases Oct. 25 in Las Cruces, one in a sheep on the university campus there and one in a cow off campus.
The commission named the area Infested Zone 25.A, which takes in most of Hudspeth County along with big eastern and southern sections of El Paso County. It issued a modified order for the two counties on Oct. 28 and a second El Paso County order on Oct. 29. Under those orders, warm-blooded animals inside an infested zone cannot leave it without prior approval from the agency. Livestock restrictions are the focus; pets are not being held back.
The fly lays eggs in open wounds, and the larvae eat living tissue, which can badly injure or kill an animal if it is not treated. Warning signs include open sores, visible maggots, a foul smell and loss of appetite. State Rep. Mary Gonzalez urged pet owners to watch their animals and see a veterinarian if they suspect a problem.
The pest resurfaced in Central America in 2023 and moved north through Mexico. The first U.S. animal case was reported in June 2026. Border cattle crossings had been shut for more than a year, and the busiest of them, at Santa Teresa, N.M., began taking cattle again on Sept. 24.
Filed under: El Paso TX Health News
