The pest that could devastate the American cattle industry was in Texas, but now it’s in New Mexico, too

Three more cases of the New World screwworm have been confirmed, including one outside the main cluster in Texas, demonstrating the difficulty of stopping a resurgent pest that could devastate the nation’s cattle industry, the U.S. Department of Agriculture announced Monday. The screwworm is actually a fly larva that eats living flesh instead of dead material. The flies lay their eggs in open wounds of animals like cattle, but wildlife, pets and occasionally even humans can be infested. The government has a program to breed sterile male flies and drop swarms of them from planes to mate with wild females, which kept screwworm contained at the southern end of Panama for decades. So far, there are five confirmed cases: three calves and a goat in Texas and a dog from neighboring Lea County, New Mexico. The small dog, which the USDA initially reported as a Texas case, lives in New Mexico and was reclassified as the first in that state. The dog had not traveled to Mexico or Texas, so authorities were investigating around the property where the pet lived. If they find infected flies, animal inspections in the area will increase, New Mexico State Veterinarian Samantha Holeck said during a virtual news conference Monday. Screwworm cases continue to climb The first two screwworm cases were discovered last week in calves a few miles apart in south Texas. A case was announced Monday in a calf in La Salle County, southwest of San Antonio, and in a goat in Gillespie County, west of Austin. In each case, officials have set up a 12-mile (20-kilometer) quarantine zone to try to slow the parasite’s advance. Along with cattle and other warm-blooded livestock, scientists worry screwworms could devastate the millions of wild white-tailed deer in Texas. Scientists expect new cases could pop up in the coming days and weeks, but it doesn’t mean screwworm is spreading rapidly, said Edward Burgess, a University of Florida entomologist who studies the fly. “When that first c