Agriculture Secretary Brooke Rollins visited the livestock inspection facility at the Douglas, Ariz., port of entry on July 29. She announced a $25 million federal commitment to build a new sterile fly dispersal facility to combat the New World Screwworm, a devastating livestock parasite advancing northward through Mexico.
The screwworm — a fly whose larvae feed on the living tissue of warm-blooded animals — poses a catastrophic threat to the U.S. cattle, hog, and sheep industries. Officials warned that a domestic infestation could cost the livestock sector billions of dollars and trigger trade restrictions with major partners.
The sterile insect technique, in which laboratory-raised sterile male flies are released to mate with wild females and produce no offspring, has historically been the most effective tool for controlling and eradicating screwworm populations. The United States waged a 30-year eradication campaign in the 20th century that successfully eliminated the pest from North America.
Secretary Rollins’ border visit elevates the screwworm threat to cabinet-level visibility. The new dispersal facility in Arizona would strengthen the barrier of sterile flies maintained along the U.S.-Mexico border region to prevent reintroduction of the parasite.
The $25 million commitment funds construction and operational startup of the facility, which will complement existing USDA screwworm prevention infrastructure. The USDA’s Animal and Plant Health Inspection Service has maintained cooperative screwworm prevention programs with Mexico and Central American nations for decades.
The U.S. livestock industry is valued at hundreds of billions of dollars annually. A screwworm outbreak would not only cause direct animal losses but could also trigger immediate export restrictions from trading partners that maintain screwworm-free status requirements, according to USDA officials.