The U.S.-Mexico border is set to reopen to cattle starting in Arizona after a more than yearlong closure to protect against the New World screwworm parasite.
News of the reopening comes nearly two months after the first confirmed case of the flesh-eating maggot in the United States.
"Arizona has consistently demonstrated its readiness to confront the challenges of screwworm, taking swift action to safeguard our cattle industry and ranchers from this latest outbreak," Arizona Gov. Katie Hobbs said in a statement.
The border is set to reopen to livestock on Aug. 24, according to the U.S. Department of Agriculture, starting with the Agua Prieta-Douglas crossing from Sonora into Arizona.
The state of Sonora, directly south of Arizona, has not reported any cases of the parasite. Sonora's important ranching sector has been calling on U.S. officials to reopen the border, pointing to the state's clean bill-of-health when it comes to the screwworm and, now, the parasite's presence on both sides of the border.
Since early June, the parasite has spread to more than 40 animals in Texas, according to USDA. It now threatens the United States' historically low cattle herd, with the potential to increase already sky-high beef prices.
In a statement announcing the planned reopening, USDA said it considers Sonora and neighboring Chihuahua the lowest-risk Mexican states for New World screwworm, due to robust animal inspection programs and geographic distance from southern Mexico, where the bulk of the country's New World screwworm cases have been reported.
For its part, Arizona's agriculture department said it plans to increase screening protocols for cattle imports as livestock begins to once again cross on foot later this summer.
An administrative order from that department states that USDA and its counterpart in Mexico have agreed that cattle crossing into Arizona will be monitored using an electronic identification method, rather than the previously used ear tags. Those ear tags caused trauma to livestock's ear tissue, which the Arizona Department of Agriculture said can increase the risk of infestation of the parasite, which burrows into wounds in living animal tissue. The parasite can be deadly if not treated quickly.
"We have worked tirelessly with USDA, the cattle industry, our sister states and Mexico to assure a safe border opening when the time came," said Arizona Department of Agriculture Director Paul Brierley in a statement. "Sonora is known for their excellent disease protocols, and we have implemented new requirements to assure the safe importation of livestock."
The United States and Mexico have also worked jointly to retrofit a facility in southern Mexico that began producing sterile New World screwworm flies this summer. It becomes one of two facilities currently producing those files, which are then dispersed throughout the region to reduce and prevent outbreaks. Experts consider the sterile fly dispersal method the most effective for combatting the parasite.
Mexican President Claudia Sheinbaum said at a press conference Monday that her country worked closely with the United States to make it possible for the border to reopen.
"You're talking about good coordination and good collaboration between both governments," Sheinbaum said.
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