USDA Reopens Southern Ports for Livestock Trade Following New World Screwworm Threat

WASHINGTON, D.C. — U.S. Secretary of Agriculture Brooke Rollins announced risk-based port re-openings for cattle, bison and equines from Mexico beginning as early as July 7. Ports were closed May 11 due to the rapid northward spread of New World screwworm (NWS) in Mexico.

The U.S. Department of Agriculture (USDA) — following collaboration with USDA Animal and Plant Health Inspection Service (APHIS) experts and their counterparts in Mexico to increase NWS surveillance, detection and eradication efforts — will begin a phased reopening of the southern ports, starting with Douglas, Ariz.

The agency reported progress in several areas since the ports were closed, including resolving challenges with conducting flights in Mexico that have allowed the USDA to conduct sterile NWS fly dispersal daily, dispersing more than 100 million flies a week.

USDA sent five teams of APHIS staff to visit, observe and gain a deeper understanding of Mexico’s NWS response. The agency reported that it has not seen a notable increase in reported NWS cases in Mexico, nor any northward movement of NWS over the past eight weeks.

“At USDA, we are focused on fighting the New World Screwworm’s advancement in Mexico,” said Rollins. “We have made good progress with our counterparts in Mexico to increase vital pest surveillance efforts and have boosted sterile fly dispersal efforts. These quick actions by the Trump administration have improved the conditions to allow the phased reopening of select ports on the southern border to livestock trade. We are continuing our posture of increased vigilance and will not rest until we are sure this devastating pest will not harm American ranchers.”

The Douglas port presents the lowest risk based upon the geography of Sonora, Mexico, and a long history of collaboration between APHIS and Sonora on animal health issues, USDA said. The agency intends to reopen additional ports over the coming weeks in New Mexico and, if it is proven safe to do so, Texas.

Additional port openings will be based on APHIS’ continuous reevaluation of the number of cases and potential northward movement of NWS, Mexico’s continued efforts to curb illegal animal movements and implementation of further rigorous inspection and treatment protocols, said USDA.

The agency provided the following port reopening timeline: 

• Douglas, Ariz. – July 7
• Columbus, N.M. – July 14
• Santa Teresa, N.M. – July 21
• Del Rio, Texas – Aug. 18
• Laredo, Texas – Sept. 15

After each reopening, USDA said it will evaluate the situation to ensure no adverse effects arise.

USDA is working with Mexico’s National Department of Health, Food Safety and Food Quality (SENASICA) on outreach, education and training efforts to raise awareness and put producers on high alert about NWS, along with utilizing the agency’s central laboratory for diagnosing cases. While Mexico has made progress on animal movement controls and surveillance, additional progress will help ensure the remaining U.S. ports reopen, said USDA.

Enhanced animal movement controls to stem illegal animal movements from the south, along with robust surveillance and NWS risk mitigations beyond checkpoints, will be critical in pushing back NWS, said USDA. APHIS technical teams continue to engage with SENASICA to improve the overall NWS posture in Mexico and implement the steps needed to keep the pest away from the U.S. border, said the agency.

Mexico will begin renovation of its sterile fruit fly facility in Metapa this week, expected to be completed by July 2026. Renovation of this facility will allow for production of 60-100 million sterile NWS flies each week, said USDA, a critical step towards reaching the goal of producing the estimated 400-500 million flies each week needed to re-establish the NWS barrier at the Darien Gap.

To ensure that USDA safely proceeds with allowing for movement of animals across the border, only cattle and bison born and raised in Sonora or Chihuahua or treated according to cattle and bison NWS protocol when entering these states will be eligible for import, said the agency. See USDA APHIS’s guidelines on Importing Live Cattle and Bison From Mexico to the United States for more information on cattle and bison import requirements.

Reopening the Del Rio (Aug.18) and Colombia Bridge (Sept.15) ports will be contingent on Coahuila and Nuevo Leon adopting the same NWS protocols for cattle and bison as those now required of Sonora and Chihuahua for cattle or bison entering those states, said USDA.

Equines may import from anywhere in Mexico. They require a seven-day quarantine at the port of entry and must import in accordance with the equine NWS protocol and other requirements detailed on USDA APHIS’s Import Horses from Mexico webpage. Approved equine facilities are available at the Santa Teresa, N.M., port and will be available for entry of horses when that port is reopened.