The Department of Agriculture has closed the livestock trade at the country’s southern ports due to concerns over a parasitic fly.
A case of New World screwworm was identified in Mexico, threatening “American livestock and our nation’s food supply.” As a result, Secretary of Agriculture Brooke Rollins announced the closure of the ports in a post on X on Wednesday night.
“Due to a newly reported northward spread of New World Screwworm in Mexico, @SecRollins has ordered the closure of livestock trade through southern ports of entry effective immediately,” read Rollins’s post. The infestation was identified in Ixhuatlan de Madero, Veracruz, a municipality in Mexico’s state of Veracruz, located near the country’s eastern coast along the Gulf of America.
“The United States has promised to be vigilant — and after detecting this new NWS case, we are pausing the planned port reopening’s [sic] to further quarantine and target this deadly pest in Mexico. We must see additional progress combatting NWS in Veracruz and other nearby Mexican states in order to reopen livestock ports along the Southern border,” Rollins said in a press release. “Thanks to the aggressive monitoring by USDA staff in the U.S. and in Mexico, we have been able to take quick and decisive action to respond to the spread of this deadly pest.”
NWS is a parasitic infestation that primarily affects livestock but can also infest any warm-blooded animal, such as birds or humans, according to the U.S. Centers for Disease Control and Prevention. Female NWS flies are “attracted to and lay eggs on and in open wounds” in animals. The larvae then “infest the tissue or flesh” of infected animals, burrowing into a wound and feeding “on the living flesh” of animals.
“One female can lay 200 – 300 eggs at a time and may lay up to 3,000 eggs during her 10- to 30-day lifespan,” noted the CDC.
Rollins’s decision follows the implementation of efforts to prevent an NWS infestation after recent detections in May in Mexican cities located approximately 700 miles from the U.S. border, according to an Agriculture Department press release. Previously, a “sweeping five-pronged plan” was implemented to eradicate NWS concerns. This plan included the enhancement of “international sterile fly production,” providing Mexico with “NWS traps and lures,” limiting the movement of animals in the affected areas, and building an “$8.5 million sterile insect dispersal facility at Moore Air Base in South Texas,” among other things.
“The United States has defeated NWS before and we will do it again,” Rollins said in June. “We do not take lightly the threat NWS poses to our livestock industry, our economy, and our food supply chain. The United States government will use all resources at its disposal to push back NWS, and today’s announcement of a domestic strategy to bolster our border defenses is just the beginning.”
“We have the proven tools, strong domestic and international partnerships, and the grit needed to win this battle,” she added.