US Rolls Out Its Strategy to Stop Flesh-Eating Screwworm

Millions of sterile flies will soon take flight from a new Texas facility, as the US launches an ambitious campaign to halt the advance of a flesh-eating parasite threatening American livestock. The strategy isn't new—the US used it to largely eradicate the screwworm population in the 1960s. But for various reasons, the screwworm has crept north through Central America and has been detected just 700 miles from the Texas-Mexico border. That has the USDA, Texas officials, and plenty of ranchers on edge.

Last month, the US halted imports of live cattle and other livestock from Mexico, a move that's already bumping up cattle prices, per the Texas Tribune. Panama is currently the only place cranking out sterile screwworm flies. Hence the USDA's Tuesday announcement that $8.5 million would be spent to get a new dispersal center at Moore Air Base in Edinburg up and running within six months. The USDA will spend another $21 million to renovate an existing fruit fly production facility in Mexico; it will ultimately generate 60 million to 100 million sterile flies a week (on top of the 100 million produced in Panama), though the AP reports it won't be ready for 18 months.

The larvae produced at the Panama and Mexico facilities will be shipped to Moore Air Base to finish growing before they're dropped by plane in Mexico and areas further south. The USDA is also toying with the idea of building a companion fly-breeding center capable of producing 300 million flies a week at the base, though construction would take as many as three years.

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There's some legislative muscle behind the effort. Several Texas lawmakers are pushing for funding and research into screwworm control, and the Texas Department of Agriculture is working on everything from parasiticide-laced cattle feed to a network of fly traps along the Rio Grande designed to alert officials should screwworms make it to the border. Officials hope these steps will stop the parasite before it crosses into Texas. As Agriculture Secretary Brooke Rollins put it this week, "We have defeated the screwworm before and we will do it again." (This content was created with the help of AI. Read our AI policy.)