Texas Lawmaker Urges Caution After First Screwworm Case Detected in Coahuila

The New World Screwworm case was detected roughly 119 miles from the U.S.-Mexico border — at nearly the same latitude as Zapata, Texas.

TEXAS (RFD NEWS) — U.S. lawmakers are raising concerns and outlining response efforts after the first confirmed detection of New World screwworm in a northern Mexican state near the Texas border. The detection, confirmed in the Mexican State of Coahuila, is drawing renewed attention from policymakers and the agricultural community, particularly in South Texas.

U.S. Representative Henry Cuellar (D-TX), who represents Texas’ 28th District located on the U.S Southern Border, says cattle producers should remain vigilant as the threat evolves.

“Well, you know that they just have to be aware because, as you know, all that that little fly — that larvae — needs just a little nick, or even through the nose or the mouth — it’s very dangerous, so they just have to be aware, you know, just like some years ago,” Cuellar told RFD News Correspondent Frank McCaffrey in an exclusive interview. “We were fighting the fever ticks. Now we are still looking at fever ticks, and we still have to deal with this new threat.”

According to the Texas Department of Agriculture, the screwworm was detected roughly 119 miles from the Texas border — nearly the same latitude as Zapata, Texas, and north and west of the Rio Grande Valley. Cuellar warns that the economic stakes are high if the pest spreads further.

“Absolutely. Look, you know, in Texas, the cattle industry is a $15.5 billion industry,” Cuellar said. “It’s a lot, and we saw the screwworms back in the ‘60s and the ‘70s. We beat him, but now we’re seeing this again, close across the river about 70, 80 miles away.”

The dangerous parasite, known for attacking open wounds in livestock and wildlife, can cause severe, often fatal infections in cattle, raising concerns for both animal health and the broader agricultural economy.

While there are many concerns among members of the South Texas ag community, and perhaps many nightmares, the congressman assures them that steps are being taken to keep them secure. Cuellar points to ongoing collaboration between the U.S. and Mexico, along with new infrastructure aimed at preventing the pest from reaching U.S. herds.

“First step, as you know, they just broke ground on this sterile fly facility,” Cuellar said. “And then, number two, I was in Mexico recently with Congressman [Michael] McCaul. We did ask about what Mexico’s doing because we got to make sure we play defense not on the one-yard line called the U.S.-Mexico border, but we got to play defense on the 20-yard line.”

Cuellar, as well as USDA officials, assures that sterile flies remain the most effective tool in combating the screwworm.

“This facility will be able to produce maybe 300 million sterile flies a week, and we need to do that to make sure we don’t see what happened — that devastation we saw in the ‘60s and ‘70s,” Cuellar said, adding that efforts extend beyond North America, noting coordination with additional partners in Mexico and also Panama.

Officials say continued surveillance, cross-border cooperation, and rapid response efforts will be key to preventing the spread of the pest into the United States.

For more information from the USDA on Screwworm detection and prevention, visit: www.screwworm.gov

Frank McCaffrey reporting for RFD News.

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RFD NEWS Correspondent Frank McCaffrey covers news from Texas, in the US-Mexico border region. He has provided in-depth coverage of immigration, the 2021 Texas freeze, the arrival of the New World screwworm, and Mexico’s water debt owed under a 1944 treaty.

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