TEXAS — The United States is suspending live animal imports along the southern border due to the spread of the New World Screwworm (NWS) in Mexico.
U.S. Secretary of Agriculture Brooke L. Rollins made the announcement Sunday. NWS has been recently detected in remote farms with minimal cattle movement as far north as Oaxaca and Veracruz, about 700 miles away from the U.S. border.
“The protection of our animals and safety of our nation’s food supply is a national security issue of the utmost importance,” Rollins said. “Once we see increased surveillance and eradication efforts, and the positive results of those actions, we remain committed to opening the border for livestock trade. This is not about politics or punishment of Mexico, rather it is about food and animal safety.”
When NWS fly larvae burrow into the flesh of a living animal, they cause serious, often deadly damage to the animal. NWS can infest livestock, pets, wildlife, occasionally birds and, in rare cases, people.
The first case of NWS in Mexico was reported to the U.S. in November 2024. That same month, the USDA shut down the border for live animal trade after a positive detection of NWS in southern Mexico. The USDA resumed imports in February 2025, after APHIS and Mexico agreed to and implemented a comprehensive pre-clearance inspection and treatment protocol to ensure safe movement and steps to mitigate the threat of NWS.
Over the last two years, screwworm has spread north throughout Panama and into Costa Rica, Nicaragua, Honduras, Guatemala, El Salvador, Belize and now Mexico.
In January, a NWS was found in a cow at an inspection checkpoint in the southern Mexico State of Chiapas, close to the border with Guatemala.
