On May 11, 2025, U.S. Department of Agriculture announced the suspension of live cattle, horse, and bison imports through U.S. ports of entry along the southern border due to the continued and rapid northward spread of New World Screwworm (NWS) in Mexico, effective immediately.

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. This import suspension will persist on a month-by-month basis, until a significant window of containment is achieved.

Any livestock currently in holding for entry into the United States will be processed normally, this includes an APHIS port Veterinary Medical Officer inspection exam and treatment to ensure they are not carrying NWS.

The U.S. previously and successfully led the eradication of NWS in the U.S. and Mexico, however this cost billions of dollars and took decades. Unfortunately, these recent detections in Mexico show that this dangerous pest is back and remains a serious threat to the health of our animals, our food supply, and the security of our country.

APHIS is releasing sterile flies through aerial and ground release at strategic locations, focusing on Southern Mexico and other areas throughout Central America.