The food supply in the US is “not at risk” from the return of the screwworm parasite in Texas, US Department of Agriculture Secretary Brooke Rollins said on Monday.
“This is not a virus, it’s not a disease, it’s just a little bug, a worm that lives in a calf wound, for example, and it can’t be treated,” Rollins said in an interview on CNBC’s “Squawk Box.”
“We have boots on the ground … we will be able to overcome this, but we will do everything we can, invest more than a billion to bring this pest back to Mexico, and finish it, as we did about 50 years ago,” he added later.
His comments came shortly before the USDA confirmed two additional cases of screwworm in Texas — one in a calf in La Salle County and one in a dog in Andrews County — bringing the total number of cases to four. Although the dog’s case was reported by a veterinarian in Texas, the animal lives in New Mexico, and the USDA considers it a New Mexico case. The department said New Mexico officials will increase monitoring and access to the area.
The USDA confirmed the first case of screwworm in Texas on Wednesday. The first cases of screwworm in the US date back to the 1960s. The possibility of this pest spreading and disrupting the food supply in the US has led to a response in Texas and Washington DC, including the appointment by President Donald Trump on Monday, John Bellinger, who has long managed food safety and distribution firms, as a senior advisor to New World screwworm preparedness.
The New World screwworm is a parasitic fly whose larvae burrow into the flesh of living warm-blooded animals, causing painful sores that can be life-threatening without treatment. The parasite poses a threat to livestock, wildlife, pets and, in rare cases, to humans.
Cattle roam a field on June 6, 2026 in La Pryor, Texas. The first case of the New World Screwworm parasite, since it was eradicated from the country in 1966, was reported in Zavala County’s La Pryor on Wednesday by the United States Department of Agriculture.
Joel Angel Juarez | Getty Images
Screwworms do not eat meat, fruits, vegetables or other food products, according to the USDA. Still, the cases show a troubling return of the parasite and raise questions about how to keep it from spreading in the US, reviving a threat the country has spent decades working to eradicate.
Texas agriculture officials, including Commissioner Sid Miller, criticized the USDA for a hasty response that failed to stop the New World screwworm from crossing the border. In response, Rollins said Miller’s latest comments are “disturbing and disturbing and very harmful to what we’re trying to accomplish.”
“You know we were going at Trump’s speed,” Rollins said.
He said the US would rely on the playbook it had been using since the late 1950s, part of which included releasing sterile insecticides to suppress the pest population. He said the US is already dropping about 10 million sterile drones a week in the affected area, in the air and on the ground.
“We’ve beaten it before, we’ve got to beat it again,” Rollins said.
