The US plans to reopen some southern border posts to Mexican livestock imports more than a year after trade was halted due to New World Screwworm (NWS).
In a statement, the US Department of Agriculture (USDA) announced a “coordinated, phased reopening” of southern livestock ports, starting with the resumption of cattle trade through the Douglas, Arizona, port of entry on 24 August.
Discover B2B Marketing That Performs
Combine business intelligence and editorial excellence to reach engaged professionals across 36 leading media platforms.
The agency will also begin simultaneous operational preparations for possible reopenings at Santa Teresa, New Mexico, and Columbus, New Mexico.
All animals entering through the reopened ports will undergo “full USDA” inspections to ensure they show no signs of NWS, the department said.
However, USDA stressed that the reopenings are “contingent” on Mexico’s adherence to a Joint Action Plan to control screwworm. It added that openings may be paused if it identifies “increased risk” through post-opening audits or other information.
US Secretary of Agriculture Brooke Rollins said: “The closure of the Southern ports of entry for the last year has been a tough but necessary action to control the spread of NWS in Mexico and protect the American livestock industry.
“Thanks to the work across the federal government as well as state, local, and industry partners, it is now safe to reopen the Douglas, Arizona, port in 30 days to resume the hundreds year old movement of cattle.”
USDA said it will initially focus on what it called the “lowest-risk” Mexican states, pointing to Sonora and Chihuahua. Both states have “strong, well-established” inspection programmes and are further from southern Mexico, where most cases are concentrated, the statement added.
Douglas, the first port of entry to open cattle trade, borders Sonora.
Following an evaluation of this initial Arizona reopening, the USDA’s Animal and Plant Health Inspection Service (APHIS) will review any resulting changes to its regional risk assessment.
If conditions remain stable, the agency will then formally consider expanding the protocol to reopen the Santa Teresa and Columbus ports to imports of live cattle, bison, and horses.
NWS is a parasitic blowfly whose larvae feed on the living tissue of warm-blooded animals.
USDA has described it as a “devastating pest” as it can infest livestock beyond cattle, including pigs, sheep, goats and horses, and can also affect dogs and wildlife.
The first NWS case in Mexico was reported in the south of the country in November 2024, triggering the closure of the border to live animal trade.
In May last year, the US administration announced a full halt on all live cattle, bison, and equine imports across the southern border due to “continued and rapid northward spread” of NWS.
The parasite was also detected in US cattle last month for the first time since 1966, which led to the launch of an “aggressive” domestic containment campaign.
USDA has previously said NWS is not a food safety issue. It said the pest spreads when flies lay eggs in wounds, not through meat.
