Three more cases of the New World screwworm have been confirmed, including one outside Texas, demonstrating the difficulty of stopping a pest that could potentially devastate the nation’s cattle industry. The U.S. Department of Agriculture announced Monday the new cases were found in a dog from New Mexico and hundreds of miles away in a goat and calf in Texas. The screwworm is actually a fly, which produces a larva that eats live flesh instead of dead material. Females lay their eggs in open wounds any any warm-blooded animal such as cattle, but wildlife, pets and occasionally even humans can be infested. Before it was irradicated in the 1960s, the fly was an annual warm-weather scourge of cattle ranchers.