SAN ANTONIO — The U.S. Department of Agriculture has confirmed 46 cases of New World screwworm infestations in the United States, including 45 in Texas and one in New Mexico, as federal and state officials continue efforts to contain the flesh-eating parasite.
The latest case involved sheep in Val Verde County and was confirmed Aug. 16, according to USDA records. It marked the first confirmed infestation since Aug. 5, when officials detected a case in sheep in Terrell County.
Admiral Michael B. Schmoyer, the USDA official overseeing the federal response, said the parasite’s northward spread has slowed. He attributed the progress to expanded surveillance, public vigilance, coordination among government agencies and targeted releases of sterile flies.
The USDA also said construction of a sterile-fly production facility in Edinburg remains ahead of schedule. Officials expect the facility to become fully operational by April 1, 2027.
Movement restrictions remain in place in parts of 23 Texas counties: Bandera, Brewster, Coke, Crockett, Edwards, Gillespie, Jim Hogg, Kerr, Kimble, La Salle, Medina, Pecos, Presidio, Schleicher, Starr, Sutton, Terrell, Tom Green, Uvalde, Val Verde, Webb, Zapata and Zavala.
Warm-blooded animals must undergo inspection and receive authorization from the Texas Animal Health Commission before leaving an infested zone.
Meanwhile, the U.S. Food and Drug Administration has authorized the emergency use of Simparica TRIO to treat New World screwworm infestations in dogs and puppies.
New World screwworm is a parasitic fly whose larvae feed on the tissue of warm-blooded animals, potentially causing severe wounds and death if left untreated.
