The United States Department of Agriculture is suspending all live cattle movement out of Mexico into the U.S. due to the risk of new world screwworm infection.
Ag secretary Brooke Rollins announced Sunday, May 11, that no live cattle, horses, or bison would be permitted into the U.S. effective immediately, due to the “continued and rapid northward spread of New World Screwworm (NWS) in Mexico.” No animals of these species transiting through Mexico will be allowed across the border, either.
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Stopping or limiting animal movement is one facet of a multi-pronged approach to eliminating NWS. The USDA says it is also using field surveillance with education and outreach to ensure prevention, treatment, and early detection and sustained sterile insect dispersal to stop the pest. The northward spread of NWS is possible through natural wildlife movements, including wildlife that transit the border region, the USDA says.
The National Cattleman’s Beef Association (NCBA) says it supports the cattle movement ban, and has been working closely with USDA to monitor the situation and has also appealed directly to the Mexican government to do more to intervene and stop the spread of NWS.
“USDA’s border closure was entirely avoidable. U.S. government officials, NCBA and leaders from affiliated state cattle industry associations have been sounding the alarm for months. Unfortunately, the Mexican government created unnecessary bureaucratic hurdles which rendered prevention efforts ineffective and allowed screwworm cases to spread unchecked beyond control points in southern Mexico,” says Colin Woodall, president of NCBA. “The Mexican government’s failure to knock down senseless obstacles has left America with no alternative but a closure of the U.S. border until the outbreak is verifiably stopped and the flies pushed back south of Panama’s Darien Gap.”
“The protection of our animals and safety of our nation’s food supply is a national security issue of the utmost importance. Once we see increased surveillance and eradication efforts, and the positive results of those actions, we remain committed to opening the border for livestock trade. This is not about politics or punishment of Mexico, rather it is about food and animal safety,” says secretary Rollins in a press release.
The first case of NWS in this latest outbreak in Mexico was reported to the U.S. in November 2024. When NWS fly larvae (maggots) burrow into the flesh of a living animal, they cause serious, often deadly damage to the animal. NWS can infest livestock, pets, wildlife, occasionally birds, and in rare cases, people. The U.S. has faced a NWS outbreak previously, and eradicated the pest.
