Texas Officials Warn of ‘Man-Eating’ Bug Found in Livestock Near Southern Mexico Border

Wildlife officials in Texas are on the lookout for the New World Screwworm fly larvae, also known as the “Man-eater,” a flesh-eating parasite, after confirmed cases of infestation in neighboring Mexico.

The Texas Parks and Wildlife Department wants hunters and outdoor recreationists in the southern part of the state to be on the lookout for this sneaky parasite: The New World Screwworm fly is especially dangerous because its larvae have the terrible ability to penetrate open wounds and body cavities, where it can feed on living tissue.

The alarming incident follows the recent finding of a cow infected with Screwworm fly larvae at a border inspection station in the Mexican state of Chiapas, which adjoins the Guatemalan border. That case, according to the Texas officials, proves the trend’s disturbing northward expansion.

The TPWD’s Wildlife Veterinarian, Dr. J. Hunter, shed more light on the role of the general public in safeguarding livestock, wildlife, and human health: “Those of us who enjoy our natural resources will have the first line of defense to not only protect but also to help respond and mitigate this threat quickly. Their eyes and ears will be critical for a quick and effective response.”

Cochliomyia hominivorax, Latin for “man-eater,” is the scientific name of the screwworm fly, a predatory insect. The female lays her eggs in natural body openings like the nostrils or open wounds. The maggots feed on the unfortunate host’s flesh immediately after hatching.

The Man-eater Screwworm fly primarily infects livestock, but it also can infect people, deer and birds.

The United States eradicated this devastating pest in 1966 through a concerted effort. Eradication efforts are still underway in Central America. The Screwworm fly is currently found in most South American countries, as well as Cuba, Haiti, and the Dominican Republic.

According to the TPWD release, the clinical signs of a Screwworm fly infestation include:

• Irritability or lethargy
• Head shaking
• Presence of a foul, decaying odor
• Social isolation
• Most significantly, the presence of maggots within wounds