What Happened
On June 3, 2026, the U.S. Department of Agriculture confirmed a case of New World screwworm in a cow in Zavala County, Texas, near the Mexican border. Since then, federal and state officials have confirmed multiple additional cases, including two more in Texas, a dog in New Mexico that had recently crossed from Mexico, and continuing detections through June 8.
The New World screwworm is a flesh-eating parasitic fly larva that burrows into the live tissue of warm-blooded animals, causing severe wounds and often death. Female flies lay eggs in open wounds or body openings. When the eggs hatch, the larvae tunnel into living flesh and feed on it.
This pest was eradicated from the continental United States in the 1960s through a combination of surveillance, quarantine and the release of millions of sterile flies—a technique that prevents reproduction. However, the screwworm remained active in parts of South America, Mexico and Central America, and has been moving northward through Mexico toward the U.S. border.
Now it is here.
Why This Matters
Texas is home to the nation's largest cattle industry. A screwworm outbreak would be catastrophic to the livestock sector. The pest threatens cattle, goats, other livestock, pets, wildlife and—in rare cases—humans.
USDA Secretary Brooke Rollins visited Texas on June 8 and announced that President Trump had appointed San Antonio businessman John Bellinger as Senior Advisor for New World Screwworm Preparedness. The agency is mobilizing 75 personnel, establishing quarantine zones, and plans to begin releasing millions of sterile flies this week from Moore Air Base in Edinburg.
The economic stakes are enormous. If the fly becomes established in Texas, it could spread rapidly and cause billions in losses to the cattle industry.
The Dumb Part With The Border Reopener
The dumb part is watching a problem that was solved 60 years ago come back because border management and pest surveillance in Mexico have failed to contain the northward advance of the parasite.
The USDA and TPR reporting noted that the Andrews County case—a dog from New Mexico that had recently crossed from Mexico—underscores a major vulnerability: companion animals can carry screwworm infections across borders with minimal inspection. Texas Tech veterinary professor Chad Cross told TPR: "We do not have guidelines in place to inspect companion animals largely when they're brought across borders."
So decades of eradication and professional livestock management can collapse because someone brought a dog from Mexico into the United States without veterinary checks. The eradication worked. Border and animal-import policy did not keep up.
The Bottom Line
Federal and state officials are treating this as an emergency and deploying significant resources. They say the sterile-fly program worked once and can work again. But the gap between "we solved this problem 60 years ago" and "it came back because we did not maintain surveillance at the border" is where the real stupid shit lives.
Ranchers in South Texas are watching their herds closely. The USDA is begging the public to report suspected cases immediately. And somewhere in Mexico, a screwworm population is moving north, reminding America that you cannot leave a solved problem unattended.
Sources
USDA APHIS: USDA Confirms Presence of New World Screwworm in the United States
Texas Public Radio: Screwworm detections in Texas grow amid expanding response
USDA: Screwworm.gov - Unified Government Response