New World screwworms, back in Mexico, threaten U.S. cattle; USDA considers sterilization control.

New World screwworms, once eradicated in the 1960s, are resurfacing in Mexico and Central America, threatening U.S. cattle ranchers. These insects lay eggs in animal wounds, causing illness and death. The USDA has banned Mexican cattle imports and supports producing sterilized male screwworms to control their population. A bill proposes building a U.S. facility for this purpose, critical for preventing economic damage to the cattle industry.