New World screwworm detected in Otero County and Texas

OTERO COUNTY, N.M. (KVIA) -- Two new cases of New World screwworm have been confirmed in Otero County, New Mexico, and Texas, according to the U.S. Department of Agriculture.

NWS is a parasitic fly whose maggots burrow into the open wounds of warm-blooded animals, including livestock. They use mouth hooks to "screw" into the flesh.

According to the USDA NWS dashboard, both cases were confirmed Wednesday. One of them was found in cattle in Otero County.

TPWD said the parasite was found in an elk in Pecos County, Texas, which includes the Fort Stockton area. The elk, a female, was hunted.

"This detection highlights the critical role hunters, landowners, outdoor enthusiasts and wildlife professionals play in helping detect and manage the spread of NWS," the TPWD said in a news release.

The Texas Animal Health Commission will modify an infested zone already established.

TPWD suggested that hunters inspect their harvest before moving the animal carcass. Signs of NWS infestation include:

• Irritated or depressed behavior
• Loss of appetite
• Head shaking
• Smell of decaying flesh
• Presence of fly larvae (maggots) in wounds
• Isolation from other animals or people

Officials said hunters should look for any wounds that might have a foul smell or maggots, especially in the eyes, ears, nose, feet, mouth and genitalia.

Suspected NWS infestations in wildlife can be reported to a TPWD wildlife biologist or 512-389-4505.

According to the U.S. Department of Agriculture, there are seven active cases of NWS in New Mexico and Texas.

In September, the Santa Teresa Livestock Crossing reopened after more than a year. The U.S. federal government halted operations at the crossing in May 2025 due to NWS concerns. Mexican authorities had to close the crossing after NWS cases were confirmed close to the border.