APHIS Halts Live Animal Imports Across US Southern Border Again Due to Screwworm

The U.S. Department of Agriculture (USDA) announced May 11 the suspension of cattle, horse, and bison imports through ports of entry along the southern border due to the rapid northward spread of New World screwworm (NWS) in Mexico, effective immediately.

Despite continued efforts by the U.S. and Mexico to stop the spread of NWS and eradicate it from Mexico, the flesh-eating parasitic fly has been recently detected in remote farms with minimal cattle movement as far north as Oaxaca and Veracruz, about 700 miles from the U.S. border, according to the USDA announcement.

USDA’s Animal and Plant Health Inspection Service (APHIS), in conjunction with Customs and Border Protection (CBP), temporarily suspended livestock imports from Mexico after the latter detected NWS in November 2024. The ban was lifted in February after the U.S. and Mexico agreed to implement a preclearance inspection and treatment protocol to mitigate the threat of NWS.