First Case of New World Screwworm Detected in Coahuila, Mexico

The Texas Department of Agriculture confirmed a New World Screwworm case about 119 miles from the Texas border, near Zapata, Texas, and north and west of the Rio Grande Valley.

Aberdeen Angus Cattle Feeding in a Feedlot at Sunset

Angus cattle feeding in a feedlot at sunset

JavierAndrés - stock.adobe.com

AUSTIN, TEXAS (RFD NEWS) — Texas Agriculture Commissioner Sid Miller is warning producers to stay alert after the first confirmed detection of New World screwworm in the Mexican state of Coahuila, bringing the pest closer to the U.S. border.

According to the Texas Department of Agriculture, the detection was confirmed roughly 119 miles from the Texas border, placing it near the same latitude as Zapata, Texas, and north and west of the Rio Grande Valley.

“This screwworm detection in Coahuila is a serious wake-up call,” Miller said. “New World screwworm has now been found only 119 miles from the Texas border — at roughly the same latitude as Zapata, Texas, and north and west of the Rio Grande Valley.”

New World screwworm is a parasitic fly whose larvae infest living tissue in warm-blooded animals, causing severe wounds known as myiasis. Officials say adult flies lay eggs in open wounds or mucous membranes, and once the larvae hatch, they burrow deeper into tissue, rapidly worsening injuries and potentially killing livestock if left untreated.

The pest poses a threat to cattle, horses, sheep, goats, wildlife, pets, and in rare cases, humans.

“This threat is advancing fast, and every Texan needs to take notice,” Miller said.

Texas officials say the state has expanded its biosecurity response in recent months, including additional trapping efforts in high-risk border areas, export facilities, and port zones.

“Texas is on the front lines,” Miller said. “Under my direction, the Texas Department of Agriculture has launched an aggressive biosecurity response, including expanded trapping with our innovative TDA Swormlure in high-risk border zones, export pens, and port areas. We are conducting weekly surveillance, maintaining rapid response capabilities, and working in close coordination with federal partners and Mexico.”

Miller said Texas is relying on lessons learned from past eradication efforts, including the sterile insect technique that helped eliminate screwworm from the U.S. decades ago.

“We’ve beaten the screwworm before through relentless vigilance and the sterile insect technique. We will beat it again — but we must deploy every tool available,” Miller said. “Texas will stay vigilant, stay aggressive, and do whatever it takes to protect our livestock, our pets, our food supply, and the livelihoods of our ranchers.”

Texas producers who suspect an infestation are encouraged to contact their veterinarian immediately or call the Texas Department of Agriculture hotline.

More information is available from the U.S. Department of Agriculture at www.Screwworm.gov.

Related Stories
While treatable with a vaccine, anthrax is a dangerous threat to cattle herd health if not identified and treated immediately.
Smaller flocks and lower lay rates are pressuring table egg supplies, even as hatchery activity edges higher.
Strong corn exports are anchoring U.S. trade, while soybean sales remain steady, but shipments lag.
Smaller slaughter numbers across beef and pork signal tighter supplies into late 2025, while record-low veal production highlights ongoing structural changes in the sector.
Beal joined us on Friday’s Market Day Report to discuss her election to NASDA’s presidency, challenges facing American agriculture, and her background as a Mainer and dairy farmer.
Chad Rezniek with the Colorado AgrAbility Project joined us as part of National Farm Safety and Health Week to discuss the growing need for behavioral health support in rural communities.

Marion is a digital content manager for RFD News and FarmHER + RanchHER. She started working for Rural Media Group in May 2022, bringing a decade of digital experience in broadcast media and some cooking experience to the team.

LATEST STORIES BY THIS AUTHOR:

The Mississippi Farm Bureau honors farmer and longtime state legislator Rep. Bill Pigott with the 2024 Distinguished Service Award.
RanchHER Jessie Jarvis is a third-generation Idaho cattle rancher and an esteemed figure in the ag industry and Western world. She seamlessly balances her roles as a business owner, influencer, podcast host, public speaker, rancher, wife and mother.
Legal issues can arise for farmers and ranchers when conducting business informally or in another state. RFD-TV Ag Law & Tax Expert Roger McEowen explores both topics in his latest Firm to Farm blog post.
Janie spends a day-in-the-life with “Of the West” founder & influencer Jessie Jarvis, for a bit of work along the historic Oregon Trail.
RanchHERs Penny Kasun and Dani Jeanne Lawrence of 7-Up Ranch in Prescott, Arizona, joined us Monday on Market Day Report to discuss the next all-new episode of the show.
Janie ventures to the desert in Prescott, Arizona for cattle branding at the 7UP ranch with Penny Kasun & Dani Jeanne Lawrence.
Agriculture Shows
Hosted by Scott “The Cow Guy” Shellady and RFD News Markets Specialist Tony St. James, Commodity Talk delivers expert insight into the day’s ag commodity markets just before the CME opens. Only on RFD-TV and Rural Radio SiriusXM Channel 147.
A look at the news, weather and commodities headlines that drove agriculture markets in the past week.
Everything profits from prairie. Soil, air, water — and all kinds of life! Learn how you can improve your land with prairie restoration, cover crops and prairie strips, while growing your bottom line.
Special 3-part series tells the story of the Claas family’s legacy, which changed agriculture forever.