The United States Department of Agriculture (USDA) has announced a temporary suspension of live cattle, horse, and bison imports through ports along the southern border, effective immediately. This measure is a direct response to the alarming spread of New World Screwworm (NWS) in Mexico, a parasitic infestation that poses a significant threat to livestock and potentially, in rare cases, even humans.
Secretary Brooke Rollins of the USDA formally announced the suspension via an X post, emphasizing the urgency and severity of the situation. She stated that the decision was prompted by the rapid northward movement of NWS within Mexico, posing a grave risk to the U.S. cattle industry. Rollins pointed out the historical precedent, recalling the devastating impact of a previous NWS invasion, which took three decades to fully resolve. The current administration aims to prevent a similar catastrophe.
The USDA issued a press release detailing the initial detection of NWS in Mexico, which was reported to the U.S. in November 2024. The agency highlighted the destructive nature of the parasite, explaining that NWS fly maggots burrow into the flesh of living animals, causing serious injury and often death. The USDA clarified that a wide range of animals are susceptible to NWS infestation, including livestock, pets, wildlife, and even birds.
The alarming aspect of the current outbreak is the geographical spread. According to the USDA, NWS has been detected on remote farms with minimal cattle movement, located as far north as approximately 700 miles from the U.S. border. This widespread presence underscores the urgency of the situation and the need for decisive action.
The U.S. and Mexico are actively collaborating on efforts to eradicate NWS before it reaches the U.S. border. The USDA has stated that its Animal Plant Health Inspection Service (APHIS) and U.S. Customs and Border Protection are jointly implementing the import restrictions, affecting live animal commodities originating from or transiting through Mexico. The suspension will remain in effect on a month-to-month basis, pending significant progress in containing the outbreak.
The USDA clarified that livestock currently held for entry into the U.S. will be processed as usual, but will undergo thorough inspection by a port veterinary medical officer and will receive treatment to ensure that they are not carrying NWS. This measure aims to prevent any accidental introduction of the parasite into the U.S.
Secretary Rollins emphasized the collaborative efforts with her Mexican counterpart, Secretary Berdegué, on the NWS response. She stated that the decision to suspend imports was a necessary step to protect the U.S. livestock industry. Rollins stressed that the protection of animals and the safety of the nation’s food supply are national security issues of paramount importance.
Rollins expressed a commitment to reopening the border for livestock trade once increased surveillance, eradication efforts, and positive results from those actions are evident. She explicitly stated that the suspension is not intended as a political statement or a punishment of Mexico, but rather as a measure to safeguard food and animal safety.
The U.S. and Mexico are pursuing a three-pronged approach to eradicate NWS. This strategy includes enhanced field surveillance with education and outreach to ensure prevention, treatment, and early detection. It also involves controlling animal movement to limit the spread of NWS and implementing sustained sterile insect dispersal, a technique used to disrupt the reproductive cycle of the fly.
The article references the historical context of NWS eradication efforts, noting that the Centers for Disease Control and Prevention (CDC) reported the successful eradication of NWS in the U.S. in the 1960s and in Mexico in the 1970s. However, the article acknowledges that these eradication efforts were extremely costly, requiring billions of dollars and spanning decades. The current situation highlights the ongoing need for vigilance and preventive measures to avoid future outbreaks.
