Consumer Economy Policy

Texas Screwworm Outbreak Prompts U.S. Push to Eradicate with Sterile-Insect Strategy

USDA Secretary Brooke Rollins said the food supply is not at risk as Texas reports a second screwworm case. The plan includes continued sterile-insect releases and a multi-year eradication effort.

Cattle in a Texas field as authorities combat the screwworm outbreak
Cattle in a Texas field as authorities combat the screwworm outbreak

Market impact

Officials frame the outbreak as a containment and eradication effort with substantial investment and interagency coordination.

Why it matters: Measures to control the screwworm affect livestock health, animal welfare policies, and regional trade dynamics.

Key numbers

  • ~10 million sterile flies per week
  • investment over a billion dollars
  • four total cases in Texas
  • first positive case Wednesday

Watch next

  • updates on case count in Texas
  • progress of sterile-insect releases
  • any new cases in neighboring states
Livestock farming Agriculture policy Food supply chains USDA Brooke Rollins Texas Department of Agriculture New World screwworm

The U.S. Department of Agriculture says the nation’s food supply is not at risk following a second confirmed case of the flesh-eating New World screwworm in Texas. USDA Secretary Brooke Rollins told CNBC’s Squawk Box that the government will rely on the same containment approach used since the late 1950s, which includes releasing sterile insects to suppress the pest’s population. Rollins stressed that the issue is a pest problem, not a virus or disease, and noted that larvae can be treated when they infect animals.

Rollins said, "This is not a virus, it’s not a disease, it’s just a little pest, a larva that lands in a calf’s wound, for example, and it can be treated." She added that boots are on the ground and that the U.S. intends to push the pest back into Mexico and ultimately eradicate it, as was done about five decades ago, with funding noted to be over a billion dollars. The remarks came as USDA officials confirmed two additional cases in Texas—one in a calf in La Salle County and another in a dog in Andrews County—raising the total to four. The dog’s case, reported by a Texas veterinarian, lives in New Mexico, which the USDA classified as a New Mexico case, prompting increased monitoring and outreach in the area.

The screwworm, a parasitic fly whose larvae damage living tissue, poses risks to livestock, wildlife, pets and, in rare cases, people. USDA officials emphasized that the flies do not infest meat, fruits, vegetables or other food products, according to their assessment. The outbreak marks a troubling return after decades of eradication efforts, and Texas agriculture officials have criticized the USDA for a slow response that allowed the parasite to cross the border. In response, Rollins defended the agency’s pace, saying Miller’s comments were disturbing and disruptive, and that the administration has been moving at what she described as “Trump speed.”

Authorities say the program is already deploying roughly 10 million sterile flies per week over the affected region, using both aerial and ground-based releases as part of the long-running eradication effort.

Looking ahead, officials stress the importance of coordinated action among state and federal agencies, with ongoing monitoring and sustained insect-releases aimed at suppressing the screwworm population and preventing further spread.