USDA announced the next milestone in the fight against New World screwworm (NWS) – the opening of a sterile fly dispersal facility in Tampico, Mexico. The Tampico facility will allow USDA to disperse sterile flies aerially across northeastern Mexico, including in Nuevo Leon.

There are 2 methods of dispersing sterile insects – aerial dispersal and ground release chambers. Aerial operations are preferred because they allow for dispersal at a steady rate through a large area and also because sterile insects may be dispersed in areas that are unreachable from the ground. Ground release chambers are used when there’s a need to quickly deploy sterile insects outside of the dispersal facility range.

USDA continues to disperse 100 million sterile flies per week in Mexico, but until now, aerial operations have been limited to southern Mexico, necessitating the use of ground release chambers in more northern areas of the country. Mass production and targeted dispersal of sterile flies remain critical components of effective response.

Although Mexico continues to confirm new cases of NWS, the overwhelming majority of these remain in the far southern part of the country, with no significant northward expansion over the past several months. Should that change, the Tampico facility will allow USDA to immediately tackle any cases that occur elsewhere in Mexico.

The two northernmost detections (approximately 70 and 170 miles from the U.S. border, respectively) occurred in Nuevo León, on September 20 and October 5, in young cattle transported from Chiapas, Mexico. Neither of those cases is still active and there have been no additional detections of NWS flies in traps or cases in animals in Nuevo Leon. USDA continues to disperse sterile insects in Nuevo Leon, and will now transition from ground release chambers to aerial dispersal in those areas.

USDA produces sterile flies for dispersal at the COPEG facility in Panama. USDA is also investing $21 million to support Mexico’s renovation of an existing fruit fly facility in Metapa, which will double NWS production capacity once complete. With ongoing support from technical experts from USDA's Animal and Plant Health Inspection Service, Mexico anticipates this sterile fly production to begin as soon as summer 2026.

USDA has also begun construction on a sterile fly dispersal facility at Moore Air Base in Edinburg, Texas, that is projected to begin operating in early 2026. APHIS is also expediting design and construction of a sterile fly production facility in southern Texas, with a targeted maximum capacity of 300 million sterile flies per week.

USDA continues to work with Mexico’s agriculture authority, SENASICA, to implement the collaborative NWS action plan and guide trapping, surveillance, and movement protocols to help stop the northward spread of NWS.

Source: USDA Press Releases, No. 0230.25 (November 13, 2025)

Last week in Mexico City, Mexico, U.S. Secretary of Agriculture Brooke L. Rollins led the largest USDA agribusiness trade mission in U.S. history. During the mission to Mexico, 41 U.S. businesses, 33 cooperators and agriculture advocacy groups, 6 State Departments of Agriculture, and 150 participants conducted more than 500 business-to-business meetings over 3 days. This was a critical opportunity for U.S. business to further trade ties and for USDA to continue its aggressive response to New World Screwworm (NWS) in Mexico and continue to hold Mexico accountable for its commitments to the 1944 Water Treaty.

In addition to participating in this trade mission, Secretary Rollins met with the team at Mexico’s National Service of Agro-Alimentary Health, Safety, and Quality (SENASICA) Headquarters NWS Control Room to showcase bilateral efforts to combat the spread of NWS in Mexico. Under Secretary for Marketing and Regulatory Programs Dudley Hoskins accompanied Secretary Rollins on the trip and visited the State of Chiapas to review NWS containment practices and enforcement.

Secretary Rollins and Under Secretary for Trade and Foreign Agricultural Affairs Luke Lindberg visited a Walmart Super Center in Mexico City and Bimbo Bakery, both major importers of U.S. products for use in their operations. The American delegation was joined by Chanel Tewalt, Director of Idaho State Department of Agriculture, Sherry Vinton, Director of Nebraska Department of Agriculture, Derek Sandison, Director of Washington State Department of Agriculture, and officials from the California, Tennessee, and Wisconsin State Departments of Agriculture.

Mexico was the top market for U.S. agricultural exports in 2024, with shipments valued at $30.2 billion.

Source: USDA-FAS Newsroom, News Release (November 13, 2025)