USDA threatens to stop Mexican cattle imports over screwworm crisis

In Mexico, the United States Department of Agriculture (USDA) issued a warning regarding the increasing threat posed by the New World screwworm, a pest notorious for its capacity to devastate livestock. On April 26, 2025, Agriculture Secretary Brooke Rollins sent a letter to the Mexican government, demanding immediate measures to combat the intrusion of this pest into American territories, thus protecting U.S. agriculture from potentially severe economic repercussions. The USDA has set a deadline of April 30 for Mexico to respond to their calls for action, or they will implement restrictions on live cattle and bison imports from Mexico. The New World screwworm larvae burrow into the flesh of living animals, making it imperative to contain their spread. This pest had been previously eradicated from the United States in 1966 through a successful program involving the release of sterilized flies to interrupt reproduction. However, recent incursions, beginning in late 2022 and continuing into 2024, have raised alarms as the pest migrated from Central America into southern Mexico. In response to the latest situation, the USDA has relied on aerial dispersal techniques to manage the screwworm population, making operational support from Mexico crucial. The USDA also pointed out that Mexican customs officials were imposing hefty import duties on essential supplies necessary for the control efforts, including sterile flies and equipment funded by U.S. taxpayers. Rollins emphasized that these delays hinder the timely response needed to stop the pest's advance. Furthermore, Mexican aviation authorities limited the operations of a U.S. contractor responsible for aerial dispersals, further increasing the urgency for cooperative action. Rollins proposed an emergency summit between U.S. and Mexican officials to strategize effective measures for screwworm containment. Both U.S. cattle producers and the government are expressing strong concern about the economic impact this pest could inflict if it fully infiltrates American livestock. Buck Wehrbein, president of the National Cattlemen's Beef Association, stated that failure to curb the screwworm could lead to significant losses for American ranchers. As the deadline approaches, pressure mounts on the Mexican government to ensure both the health of their livestock and the economic interests of both nations are safeguarded.