The New World screwworm, a parasitic fly that harms each cattle and people and was as soon as eradicated from the U.S. after greater than three many years of effort, is elevating new considerations amid an outbreak in Mexico. In response to the looming menace, the U.S. Division of Agriculture (USDA) has introduced a halt on imports of cattle, bison, and horses by the southern border.
The New World screwworm produces larvae that feed on the flesh and blood of livestock, pets, wildlife, birds, and, in some circumstances, people, inflicting painful infestations that may result in probably deadly injury to their hosts. It was eradicated within the U.S. in 1966 after billions of {dollars} had been spent on an operation that concerned releasing tons of of hundreds of thousands of sterile grownup flies, which might mate with wild females and in the end forestall them from laying viable eggs.
The current menace emerged after the maggot fly was detected on distant farms in Mexico with minimal cattle motion, reaching as far north as Oaxaca and Veracruz, about 700 miles from the U.S. border.
“Because of the menace of New World Screwworm, I’m asserting the suspension of reside cattle, horse, & bison imports by U.S. southern border ports of entry efficient instantly. The final time this devastating pest invaded America, it took 30 years for our cattle business to get well. This can’t occur once more,” the USDA Secretary, Brooke Rollins, introduced in an X submit.
The primary case of infestation in Mexico was reported to the U.S. in November 2024, following which the USDA shut down the border for reside animal commerce. Commerce resumed in February 2025, after the U.S. Division of Agriculture’s Animal and Plant Well being Inspection Service (APHIS) and Mexican authorities put in place a radical inspection and remedy course of to soundly handle animal motion and cut back the chance of New World screwworm.
The USDA introduced that APHIS is deploying sterile flies by air and on the bottom at key websites, specializing in southern Mexico and different components of Central America.
“The safety of our animals and the protection of our nation’s meals provide is a nationwide safety subject of the utmost significance. As soon as we see elevated surveillance and eradication efforts, and the optimistic outcomes of these actions, we stay dedicated to opening the border for livestock commerce. This isn’t about politics or punishment of Mexico, moderately it’s about meals and animal security,” Secretary Rollins mentioned in a information launch.
