The first confirmed case of New World screwworm in a horse has been detected in Presidio County, Texas, according to the U.S. Department of Agriculture.

What we know: The U.S. Equestrian Federation said the parasite was detected in the hind leg of a working ranch horse in Presidio County on Sept. 9. It's the first reported case of NWS in a horse in the United States.

U.S. Equestrian is urging horse owners to check their horses every day for wounds, swelling, drainage, foul odors and maggots.