The U.S. Department of Agriculture on July 24 announced that southern cattle ports suspended because of the New World Screwworm crisis will begin a phased reopening on Aug. 24, contingent on Mexico’s continued compliance with a bilateral Joint Action Plan.
The suspension had halted live cattle imports from Mexico and contributed to tighter U.S. beef supplies, affecting prices for producers and consumers. The phased reopening will allow cattle to move through designated ports of entry under enhanced inspection and treatment protocols designed to prevent screwworm from entering the United States.
New World Screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals, causing severe injury and death in livestock if left untreated. The parasite was eradicated from the United States in the 1960s through a sterile insect technique program, but outbreaks in Mexico earlier this year triggered the emergency port closures.
USDA separately committed $25 million on July 29 to construct a new sterile fly dispersal facility in Arizona to bolster eradication efforts. The facility will produce and release sterile male screwworm flies that mate with wild females but produce no offspring, gradually suppressing the population.
The sterile fly technique has been the primary biological tool for screwworm eradication since the 1950s. The new Arizona facility will supplement existing production capacity at a USDA-operated plant in Panama.
American cattle ranchers along the southern border have pressed USDA to reopen the ports as quickly as possible, arguing that the suspension has disrupted supply chains and driven up costs. The Aug. 24 reopening date gives the industry 21 days to prepare for the resumption of cross-border cattle movement.
The U.S. cattle industry is valued at more than $100 billion, and a domestic screwworm outbreak could cause catastrophic losses.