The U.S. Department of Agriculture has confirmed the presence of a flesh-eating, parasitic fly in the U.S. 

The maggots of the New World screwworm burrow into the flesh of living animals, which threatens the health of pets, wildlife and livestock. In some cases, birds and people can also be affected. 

U.S. Agriculture Secretary Brooke Rollins said on Tuesday that the flies were detected 25 miles from the U.S.-Mexico border, contradicting local concerns that the insects had already arrived in the country. 

The USDA said on Wednesday that the maggots of the fly were found in a 3-week-old calf in Zavala County, Texas, which is west of San Antonio. To date, it's the only positive detection in the U.S. 

“All models showed New World Screwworm entering the country in 2025; however, thanks to the hard work across the entire Trump administration and our industry, state, and local partners, we were able to buy time for this moment. Protecting our livestock industry is a national security issue of the utmost importance, and USDA is wasting no time in taking action,” Dudley Hoskins, under-secretary for marketing and regulatory programs at the USDA, said in a statement. 

The USDA and Texas officials are establishing an incident command team and a 12-mile wide zone around the infested area, where they will implement quarantines and control movements, in addition to other measures to stop the spread of the insect, according to the USDA press release.