No date to let Mexican cattle into US as work on sterile flies continues

Veterinarians examine cattle at a ranch that supplies livestock for export to the U.S., in Zamora, northern Mexico, Monday, July 28, 2025, as the U.S. border remains closed to Mexican cattle imports because of screwworm concerns.

Want to see more of NewsNation? Get 24/7 fact-based news coverage with the NewsNation app or add NewsNation as a preferred source on Google!

MEXICO CITY, Oct 29 (Reuters) – Mexican Agriculture Minister Julio Berdegue said on Wednesday that Mexico and the United States have not yet set a date to resume Mexican cattle exports amid an outbreak of the flesh-eating screwworm parasite.

Berdegue said he spoke to U.S. Agriculture Secretary Brooke Rollins in a video conference and that they had made advances but still did not have a date for reopening the border to Mexican cattle.

They agreed to test modular mobile plants in Mexico that could increase sterile fly production by up to 20 million additional flies each week if successful, Berdegue said, adding that they had never before been used in the world.

The U.S. government has kept its border mostly closed to Mexican cattle imports since May as the screwworm, which infests and can kill livestock if untreated, has moved from Central American into Mexico, rattling the livestock sectors of both countries.

The technique involves breeding millions of flies, sterilizing them with radiation, and releasing them into the wild. When sterile males mate with wild females, no offspring are produced, and the population collapses over time.

Mexico is also working to open a sterile fly plant in southern Chiapas state, with the help of a $21 million investment by the U.S. It is expected to eventually produce 100 million flies weekly.

“We will only be able to get it out of the country once we have the additional 100 million flies,” Berdegue said during President Claudia Sheinbaum’s daily press conference.

(Reporting by Cassandra Garrison and Natalia Siniawski)

World

Copyright 2026 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.