After a year-long-plus ban on cattle trade due to concerns over parasitic fly outbreaks, and despite growing cases of New World Screwworm on both sides of the international border, the U.S. Department of Agriculture is reopening a second port of entry at the southern border for livestock imports.
Arizona's port of entry in Douglas, and its sister Mexican city of Agua Prieta, was the first on Aug. 24. The Santa Teresa Port of Entry in New Mexico will reopen on Sept. 24.
The agency increased inspection protocols for cattle imports and worked for months with Mexican counterparts, as well as the Arizona and New Mexico departments of agriculture ahead of the reopening. Recent detections of screwworm cases in New Mexico, along with new cases in the Mexican states
of Sonora and Chihuahua, haven't changed reopening plans.
A horse on a New Mexico ranch, 50 miles from the Arizona state line, was found with a wound infested with maggots from Cochliomyia hominivorax, or New World Screwworm, the USDA confirmed on Sept. 17. It's the second case in the neighboring state. No cases have been detected in Arizona so far.
"Teams immediately began implementing actions in the NWS Response Playbook — establishing a 20-km infested zone in the area, advancing the epidemiological investigation, rapidly deploying sterile NWS flies, and expanding trapping and wildlife surveillance," the USDA Animal and Plant Health Inspection Service wrote.
The USDA has confirmed 50 cases in the United States as of Sept. 23, including 30 reported in June. Only two cases, reported in September, are active.
Reopening the border to livestock trade is based on "recent evidence and data," USDA Secretary Brooke Rollins told The Republic in August.
After the first case of screwworm was reported in Texas, authorities acted fast to establish surveillance areas, conduct sterile fly releases and medicate affected animals. Because of this, she suggested, the United States has few active cases "when everybody thought it'd be in the thousands at this point," Rollins said.
Ongoing surveillance and sterile fly drops
The resumed operation of trade through Douglas "exceeded all expectations," Rollins said at a press conference outside the Santa Teresa Port of Entry.
In the first week after the reopening, some 750 head of cattle crossed through the Douglas-Agua Prieta port of entry. Currently, some 1,200 head of cattle are crossing each week, a spokesperson with Sonora's Secretary of Agriculture told The Republic.
The USDA is confident in its capacity to face the parasite presence in the United States, Rollins added. The agency has conducted "1,800 drone flights and surveyed 110,000 wildlife," and used trail cameras to monitor any signs of the parasite, she said. The agency has released more than a billion New World Screwworm sterile flies in the United States.
Sonora detected its first New World Screwworm case on Aug. 19, five days before the reopening of the Douglas port of entry. Mexico's Secretary of Agriculture, Ranching, Hydric Resources, Fisheries and Aquaculture reported 85 cases in the border state as of Sep. 22.
The Mexican agency, working alongside Sonoran counterparts and livestock associations, has released about 50 million sterile flies to stop the reproduction of the parasite and contain the spread, Francisco Sandoval, a communication specialist with the Secretary, told The Republic.
Following the detection of the parasite in Grant County, New Mexico, the Arizona Department of Agriculture posted in its social media accounts that "there are currently zero cases in Arizona."
"We remain prepared and vigilant and we urge any livestock owners, pet owners, and other animal industry partners to continue to monitor animals and report any unusual wounds consistent with NWS," the post read.
The public can report suspected cases to diseasereporting@azda.gov.
Clara Migoya covers agriculture and water issues for The Arizona Republic and azcentral.
This article originally appeared on Arizona Republic: More cattle can cross US-Mexico border as new screwworm cases surface
