Livestock Trade with Mexico Halted over New World Screwworm Outbreak

The U.S. has temporarily halted livestock trade with Mexico due to an outbreak of New World screwworm among cattle, bison, and horses detected in Veracruz.

U.S. Secretary of Agriculture Brooke Rollins announced the decision to halt the trade on Wednesday.

“I have ordered an immediate shutdown of live cattle, bison, and horse trade through the southern U.S.-Mexico border. This decisive action comes after Mexico confirmed another case of New World Screwworm [NWS] in Veracruz. As promised, [USDA] remains vigilant to ensure the protection of America’s livestock and food supply,” Rollins wrote on X.

“The United States has promised to be vigilant — and after detecting this new NWS case, we are pausing the planned port reopening’s to further quarantine and target this deadly pest in Mexico. We must see additional progress combatting NWS in Veracruz and other nearby Mexican states in order to reopen livestock ports along the Southern border,” Rollins said in a statement. “Thanks to the aggressive monitoring by USDA staff in the U.S. and in Mexico, we have been able to take quick and decisive action to respond to the spread of this deadly pest.”

According to Drovers, Mexico’s National Service of Agro-Alimentary Health, Safety and Quality reported on July 8 “a new case of New World screwworm (NWS) in Ixhuatlan de Madero, Veracruz, Mexico, which is approximately 160 miles northward of the current sterile fly dispersal grid on the eastern side of the country and 370 miles south of the U.S./Mexico border”:

This new northward detection comes approximately two months after northern detections were reported in Oaxaca and Veracruz, less than 700 miles away from the U.S. border, which triggered the closure of our ports to Mexican cattle, bison and horses on May 11, 2025.

While USDA announced a risk-based phased port re-opening strategy for cattle, bison and equine from Mexico beginning as early as July 7, 2025, this newly reported NWS case raises significant concern about the previously information shared by Mexican officials and severely compromises the outlined port reopening schedule of five ports from July 7 to Sept. 15. Therefore, in order to protect American livestock and the U.S. food supply, Secretary of Agriculture Brooke Rollins has ordered the closure of livestock trade through southern ports of entry effective immediately.

The USDA defines New World screwworm as a “devastating pest” with larvae that burrows “into the flesh of a living animal,” causing “serious, often deadly damage.”

“The name screwworm refers to the maggots’ feeding behavior as they burrow (screw) into the wound, feeding as they go like a screw being driven into wood,” noted the USDA. “Maggots cause extensive damage by tearing at the hosts’ tissue with sharp mouth hooks. The wound can become larger and deepen as more maggots hatch and feed on living tissue. As a result, NWS can cause serious, often deadly damage to the animal.”

Paul Roland Bois directed the award-winning Christian tech thriller, EXEMPLUM, which has a 100% Rotten Tomatoes critic rating and can be viewed for FREE on YouTube, Tubi, or Fawesome TV. “Better than Killers of the Flower Moon,” wrote Mark Judge. “You haven’t seen a story like this before,” wrote Christian Toto. A high-quality, ad-free rental can also be streamed on Google Play, Vimeo on Demand, or YouTube Movies. Follow him on X @prolandfilms or Instagram @prolandfilms.