A deadly livestock pest sparks trade tension—and could soon hit American wallets at the grocery store.
The U.S. Department of Agriculture (USDA) has suspended the importation of live cattle from Mexico in response to an outbreak of the New World screwworm—an aggressive pest that feeds on the living tissue of mammals and poses a grave threat to livestock. The suspension, which began Sunday, is expected to last at least 15 days and will be reviewed monthly, pending progress in containing the outbreak.
The decision, confirmed by U.S. Secretary of Agriculture Brooke Rollins, came after screwworm larvae were detected in the Mexican states of Oaxaca and Veracruz, roughly 1,125 kilometers (700 miles) from the U.S. border. Rollins emphasized the urgency of the matter, recalling that the last major screwworm invasion in the U.S. took three decades to fully eliminate and caused significant economic losses in the cattle industry.
“The last time this devastating pest invaded the United States, our cattle industry took 30 years to recover. We cannot allow this to happen again,” Rollins said in a statement.
Despite a bilateral agreement earlier that week to jointly combat the pest, the U.S. acted unilaterally, a move that has drawn criticism from Mexico’s Agriculture Secretary, Julio Berdegué.
“This unilateral measure does not contribute to our joint strategy against the plague,” Berdegué posted on X (formerly Twitter), expressing concern that the suspension could undermine collaborative efforts.
The USDA clarified that cattle already waiting at the border for entry into the U.S. will be allowed through, following standard health screenings and pest-control treatments.
According to Mexico’s Secretariat of Agriculture, the screwworm is a vector pest caused by fly larvae that consume the flesh of live mammals. While primarily affecting livestock such as cattle, it can also pose a risk to wildlife and, in rare cases, humans. The USDA labeled the current spread of the pest as “unacceptable,” even though affected regions in Mexico have relatively low cattle movement.
The last border shutdown linked to a screwworm outbreak occurred in late 2024, when live cattle and horse imports from Mexico were temporarily halted. That suspension lasted over three months and was only lifted in February 2025 after new biosecurity protocols were established.
The U.S. is heavily reliant on Mexican cattle imports to meet domestic demand. In 2024 alone, the U.S. imported over 2 million head of cattle—approximately 1.25 million of which came from Mexico, USDA data shows.
Any disruption to this supply chain could place upward pressure on U.S. beef prices. With demand remaining steady and supply potentially shrinking, meat processors may face higher costs, especially if they must source cattle from more distant countries or rely more heavily on domestic herds.
Short-term effects may be mitigated by existing cattle already in the U.S. pipeline, but if the suspension continues or expands, consumers could begin seeing price hikes at grocery stores and restaurants as early as summer 2025.
Livestock analysts caution that even a 15-day halt—if extended—could ripple through the beef market, affecting feedlot operations, packing plants, and eventually retail pricing.
Both the U.S. and Mexico have agreed to continue talks. While U.S. officials stress the suspension is not politically motivated and is purely a food and animal safety precaution, Mexican authorities have warned that ongoing unilateral decisions may undermine regional cooperation in controlling animal diseases.
For now, close monitoring and coordinated mitigation strategies will be key to determining whether this remains a short-term disruption—or the beginning of a longer, costlier trade and food security issue.
