U.S., Mexico work to fight New World Screwworm, restore trade

DAILY Bites

• Vilsack called for expedited approval of inspection facilities to safely resume cattle imports from Mexico following a screwworm outbreak.

• Emergency funding increased sterile fly production fivefold, bolstering efforts to combat New World Screwworm in Mexico and prevent further spread.

• Cattle import suspension reduced U.S. supply by up to 300,000 head, affecting the market but supporting feeder cattle prices.

DAILY Discussion

Outgoing U.S. Department of Agriculture Secretary Tom Vilsack addressed a letter to Mexico’s Secretary of Agriculture Julio Antonio Berdegué on Friday addressing efforts to restore cattle trade between the two nations following the detection of new world screwworm in Mexico.

While progress has been made, Vilsack emphasized the need for swift action to complete the process and minimize disruptions to the agricultural sector.

The letter acknowledged the technical collaboration between the United States and Mexico, which resulted in a full agreement on protocols for addressing NWS by December 12, 2024 — just weeks after its discovery. Vilsack commended the ongoing inspections of pre-export NWS facilities and urged Mexico to expedite necessary modifications for final approval, noting that reopening trade is crucial for maintaining a stable and affordable food supply.

Vilsack further discussed the U.S. efforts to battle a potential screwworm reemergence. Emergency funding has enabled a fivefold increase in sterile fly production and enhanced regional efforts, including surveillance, dispersal, and educational initiatives.

Mexico’s contributions, including sterile fly releases and movement controls, have been part of those efforts to prevent the further spread of the pest into northern regions. Vilsack requested support for establishing two new sterile fly dispersal centers in southern Mexico to strengthen these efforts and push the pest southward toward the Darien Gap.

The temporary suspension of cattle imports, implemented on November 22, 2024, has significantly impacted the U.S. cattle market. An estimated 250,000 to 300,000 fewer head of cattle have been imported, reducing supply and bolstering feeder cattle and calf prices. Critical steps to resume trade include facility inspections, implementation of a seven-day quarantine, and prioritizing the Santa Teresa, New Mexico, port for reopening.

»Related: Screwworm eradication lessons from a longtime veterinarian