New Screwworm Case Delays Port Openings
The U.S. Department of Agriculture (USDA) has paused its phased reopening of southern livestock ports after a new New World Screwworm (NWS) case was reported in Veracruz, Mexico. The infected area is just 370 miles south of the U.S. border and north of the current sterile fly dispersal zone.
This new detection, confirmed by Mexico’s agricultural agency SENASICA, follows earlier cases in Oaxaca and Veracruz. The earlier outbreaks led to the closure of U.S. ports to Mexican cattle, bison, and horses on May 11, 2025. The planned port reopenings, scheduled between July 7 and September 15, are now on hold to prevent NWS from reaching U.S. herds.
“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,” said U.S. Secretary of Agriculture Brooke L. Rollins. “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.”
To combat the pest, USDA is holding Mexico accountable for containing NWS using surveillance, animal movement restrictions, and science-based eradication methods. The U.S. is also launching additional efforts, including a new sterile fly dispersal facility in South Texas and the design of a domestic fly production center.
In June, Secretary Rollins introduced a Bold Plan to combat NWS. It involves enhancing border biosecurity, increasing eradication efforts in Mexico, and expanding domestic readiness. These actions are part of a broader USDA strategy, working closely with border states such as Arizona, New Mexico, and Texas.
USDA staff continue monitoring efforts within Mexico to ensure strong biosecurity measures are being followed, aiming to keep American livestock safe from this harmful pest.
Photo Credit: usda