New World screwworm infestations reported in Texas, New Mexico and Mexico

Veterinary officials in Mexico have confirmed several cases of the New World screwworm (Cochliomyia hominivorax) in dogs, cattle, horses and even a homeless person in Matehuala. The outbreak follows the cancellation of a sterile‑fly release program and the opening of the Guatemalan border, which authorities say introduced infected livestock.

In the United States, the Texas Animal Health Commission reported the parasite in 13 counties and 24 establishments, prompting movement restrictions. A stray dog in Lea County, New Mexico, was identified as the state’s first confirmed case after initial misreporting. The USDA and state agencies have issued alerts for pet owners, urging daily inspection of wounds, immediate veterinary care, and avoidance of home removal of larvae.

Authorities in Hawaii are also monitoring for detections on the mainland, although no additional cases have been reported there. Veterinarians stress that the larvae feed on living tissue and can cause severe injury or death if untreated, making early professional treatment essential for both livestock and companion animals.