A drone view shows cattle waiting to be exported to the United States after the U.S. suspended cattle imports following the detection of the parasite in southern Mexico, at the Chihuahua Regional Livestock Union, in Nuevo Palomas, Mexico May 15, 2025.
The reopening will begin on July 7 at the port in Douglas, Arizona, selected for its low risk and established cooperation between Sonora officials and the USDA’s Animal and Plant Health Inspection Service. Imports of these animals were halted on May 11 after the screwworm, a fly species long eradicated in the U.S., was detected advancing northward in Mexico. This pest’s maggots can infest livestock and wildlife, causing severe, often fatal damage.
Additional ports are scheduled to reopen in stages: Columbus, New Mexico, on July 14; Santa Teresa, New Mexico, on July 21; Del Rio, Texas, on August 18; and Laredo, Texas, on September 15. The USDA will monitor conditions after each reopening to verify the effectiveness of strengthened control measures.
To address the screwworm threat, the USDA announced on June 18 plans to establish a sterile fly dispersal facility in Texas and committed $21 million to modernize a similar facility in Mexico for producing sterile flies. These efforts focus on enhancing surveillance and curbing the pest’s spread.
“We have made good progress with our counterparts in Mexico to increase vital pest surveillance efforts and have boosted sterile fly dispersal efforts,” USDA Secretary Brooke Rollins said in a statement. “We are continuing our posture of increased vigilance and will not rest until we are sure this devastating pest will not harm American ranchers.”
Mexico’s government stated that Agriculture Minister Julio Berdegue requested faster timelines for some port reopenings, and USDA Secretary Rollins agreed to consider these requests. Starting July 7, Mexico will restrict livestock movement from affected areas to its central and northern regions unless accompanied by inspection and treatment certification for screwworm. A bilateral technical meeting was scheduled for Tuesday to review these agreements.
The phased reopening reflects a commitment to safeguarding U.S. agriculture while facilitating trade. Through ongoing collaboration with Mexico, the USDA aims to ensure effective pest management, protecting livestock industries in both nations.
