Sign up for TPR Today, Texas Public Radio's newsletter that brings our top stories to your inbox each morning.
Mexico’s cattle industry is facing what Álvaro Bustillos Fuentes calls “the worst storm in the history of our livestock industry,” a convergence of drought, disease and disrupted trade that has cut northern Mexican ranchers off from the U.S. market that shaped them for more than a century.
Bustillos, president of the Chihuahua Regional Cattlemen’s Union (UGRCh) told TPR the blow came after three years of punishing drought, which he described as the worst in 40 years. Then came the return of the New World screwworm, a flesh-eating parasite that had been eradicated from the region decades ago, and the U.S. decision to close the border to live Mexican cattle as the pest moved north from Central America into Mexico.
For Chihuahua, one of Mexico’s most export-dependent cattle regions, the shutdown has upended a business model built around cross-border integration. Mexican ranches raise calves that are often sent north to be finished in U.S. feedlots and processed in American plants. Before the closure in 2025, the United States formerly imported more than one million cattle a year from Mexico, representing 4% to 5% of all cattle sold for U.S. beef production, according to industry data.
“In more than 120 years of commercializing cattle into the United States, there have only been three closures,” Bustillos Fuentes said. One was during the Mexican Revolution, the second was because of foot-and-mouth disease, and this is the third.
Bustillos estimates Chihuahua alone would normally export about 500,000 head of cattle a year. With the U.S. market closed, producers are being forced to sell animals at far lower prices and into a market that was never designed to absorb them.
“We are leaving about $1,000 per head on the table,” he explained. “That means Chihuahua is leaving $500 million a year in opportunity cost.”
The losses are felt beyond ranchers. Cattle exports bring dollars to transport networks, feed suppliers, rural services and communities with few alternative engines of growth. Roughly 1.2 million head that would normally move north remain in Mexico according to Bustillos, depressing local prices.
But the crisis is not only a trade story. It is also one about a regional eradication system that did not expand fast enough as the parasite moved north.
The U.S. could have done more
The New World screwworm, caused by the larvae of the fly Cochliomyia hominivorax, feeds on the living tissue of warm-blooded animals — and rarely, humans. It was eradicated from the U.S., Mexico and Central America through a decades-long campaign built around the sterile insect technique: male flies are mass produced, sterilized and released so that wild females lay eggs that do not hatch.
According to FAO/IAEA reports, and U.S. records, the New World screwworm has been present in the region for decades. The sterile insect technique was central to a 45-year campaign that pushed the parasite from the United States, Mexico and Central America down to Panama by 2006, where sterile flies maintained a barrier in the Darien Gap. The barrier held until 2022, when the fly began spreading northward from Panama, exposing how dependent the region remained on a limited production network.
By June this year, the emergency had crossed into the U.S. Center for Infectious Disease Research and Policy reported detections in New Mexico and Texas — the country’s top cattle state and home to about $17 billion worth of cattle.
For years, the sterile-fly barrier relied heavily on COPEG, the U.S.-Panama commission that operates the production facility in Panama. USDA jointly manages and funds that facility with Panama’s Ministry of Agriculture Development. It produces about 100 million sterile flies a week, far short of what’s needed. FAO said in June that responding to the emergency could require up to 600 million sterile flies per week, while emergency efforts are facing a shortage.
Governments are now trying to expand the system. In late June, U.S. and Mexican officials inaugurated a sterile-fly production plant in Metapa de Domínguez, Chiapas, near the Guatemalan border. The USDA says it is investing $21 million to renovate and convert the existing facility, which is expected to add 60 million to 100 million sterile flies a week once complete. President Claudia Sheinbaum called it “a good example of development cooperation” and “how cooperation should be between the United States and Mexico,”
The United States is also building a production facility at Moore Air Base in Edinburg, Texas, with initial operations targeted for November 2027 at 100 million sterile flies a week and a projected full capacity of 300 million. USDA has already completed a separate dispersal facility at the same site, capable of releasing up to 100 million sterile flies a week along the U.S.- Mexico border.
Together, the planned Metapa expansion and the Texas production facility could eventually add up to 400 million more sterile flies a week, but much of that capacity is still being built.
A political and technical debate
Sources told TPR the U.S. was not blindsided. The Panama-U.S. commission expressed concerns starting in 2022 and declared an outbreak in Darién in 2023, and Panama’s agriculture ministry reported APHIS participation in meetings and field work as the parasite spread beyond the barrier.
The Metapa plant, and the expansion of the U.S, facilities are both central to the next stage of the response. But it also underscores the timing problem: the region is increasing sterile-fly capacity after the parasite has already moved through Central America, into Mexico and now, into the United States.
That gap helps explain why the debate has become political as well as technical. U.S. officials have pressed Mexico to strengthen surveillance and control animal movements. Mexican producers, meanwhile, point to the long-standing binational nature of the eradication system and the region’s dependence on fly production outside Mexico.
All U.S. southern ports of entry remained closed to livestock trade and that its “highest priority remains protecting the United States.” The Centers for Disease Control and Prevention said no locally acquired human cases and that the risks are still very low.
For Mexican ranchers, the presence of cases in Texas changes the argument. What began as a U.S. effort to keep the parasite out has become a binational containment effort with consequences on both sides of the border. Bustillos said that should push both countries toward protocols based on science, inspections and regional risk rather than a blanket closure.
“Now that the United States also has the sanitary contingency and becomes positive for screwworm, we have to sit down and establish protocols,” he said. “We cannot strangle the industries.”
Bustillo's immediate fear is that the closure will last long enough to permanently reshape Chihuahua’s cattle economy. But he said the solution is still possible if both governments treat the problem as shared.
“There has to be understanding between both countries, so we do not strangle the economic part of the industry,” he said.
