With tighter checks for flesh-eating screwworm, a border crossing reopens

With the all-clear from U.S. agriculture inspectors, Mexican cattle began moving on Monday through a border crossing in New Mexico that had been closed for nearly two years as both nations work to stop the flesh-eating New World screwworm from spreading. The screwworm — actually a fly larva that burrows into the flesh of livestock, pets and even humans — has threatened the $113 billion U.

S. cattle industry. Containment efforts have cost jobs and trade in border communities, cutting off a source of cattle as the U.S. struggles to rebuild drought-depleted herds. Reopening crossings could help ease that squeeze, although experts caution that shoppers shouldn't expect quick relief on beef prices.

The port at Columbus, New Mexico, is the third to resume Mexican cattle imports under new safeguards, which include tests, shots and inspections that happen before an animal even gets close to the border. Officials and ranchers in the two countries say layers of treatment and inspection give them confidence that imported livestock won't carry screwworm through the ports.

But flies can buzz across the border on their own, meaning ranchers, hunters and pet owners should remain vigilant. The parasite was an annual livestock scourge before being largely eradicated in the U.S. in the 1960s. It reappeared in Mexico in 2024, and the first confirmed U.