Stephen Diebel

The New World screwworm fly has reappeared in the U.S., threatening the cattle industry with its flesh-eating larvae. An infestation was confirmed in a 3-week-old calf in Texas, marking the first case since 1966, after the fly was previously eradicated through sterile male fly releases. Officials emphasize the fly does not infest food and is unlikely to disrupt beef production.

The New World screwworm fly, which had been eradicated in the U.S. since 1966, has reappeared in south Texas, threatening the $113 billion cattle industry. The infestation was detected in a 3-week-old calf near the U.S.-Mexico border, with the fly having previously spread in Mexico since late 2024. Federal officials confirmed this is the first case in Texas in over 50 years, using historical eradication methods like sterile male fly releases.

The New World screwworm fly, which had been eradicated in the U.S. since 1966, has reappeared in Texas after being detected in Mexico in 2024. The fly's larvae infest open wounds of warm-blooded animals, posing a significant threat to the $17 billion Texas cattle industry. Federal and state officials are monitoring the situation as the parasite spreads, with historical eradication efforts involving sterile male fly releases.