Democrats and Republicans say the other is responsible for the pest’s entry into the U.S.
New World screwworm (NWS) is in the U.S. and lawmakers on both sides of the aisle say the other is to blame.
The USDA confirmed the presence of NWS on June 3 in a three-week-old calf in Zavala County, Texas.
Since then, the number of confirmed cases of NWS in the country has risen to at least five, with a dog and other cattle among the affected animals.
Republicans put the blame on Democrats, specifically under President Biden’s watch.
“This is a direct result of the Darien Gap (a remote stretch of land between Colombia and Panama) being breached in 2022 thanks to the reckless open border policies of Biden-Harris that allowed (NWS) to SURGE through Central American and hit Mexico by 2024,” Agriculture Secretary Brooke Rollins said on X on June 10.
She also testified before the Senate ag committee on June 10 about the screwworm situation and other USDA issues.
In 2023, Panama saw more than 6,500 cases of NWS, up from the average of about 25 per year.
NWS spread north through Costa Rica, Nicaragua, El Salvador, and other countries in 2024, reaching Mexico by November.
U.S. Senator Roger Marshall from Kansas also believes Biden’s border policy allowed for unwanted people and the NWS to enter the country.
“This is another thing we can thank Joe Biden for – that when millions of people came out of Central America, they brought this screwworm with them. It was on their pets, maybe on their flesh as well,” he said in an interview with Newsmax.
The screwworm enters animals, and in some cases, humans, through open wounds.
One female can lay up to 300 eggs, which hatch into larvae. These larvae then use sharp mouth hooks to burrow into living tissue.
On the other side, Democrats say Republicans bear responsibility for NWS entering the U.S.
Senator Patty Murray from Washington, for example, says NWS wouldn’t be in the U.S. if the Republicans didn’t cut funding for a monitoring program.
“Let’s be clear about what happened: DOGE (Department of Government Efficiency) cut the programs and staff that tracked dangerous outbreaks like screwworm,” she said on X on June 8. “So this has nothing to do with Joe Biden, but Trump and DOGE definitely screwed our cattle industry.”
Rep. Jimmy Gomez of California agrees.
“The screwworm monitoring program in Central America was cut by the Trump administration’s DOGE in early 2025,” he said on Facebook. “Once again, this administration is desperately trying to downplay the problems they started.”
A December 2024 USDA release says the department allocated $165 million in emergency funding to help stop the spread of NWS.
With NWS present in the U.S., the other USMCA trading partners are taking precautions.
Canada issued a temporary ban on livestock from Texas.
And Mexico blocked most live animal imports from the U.S.