Cameras in Central American Forests Record Screwworm in Wildlife and Cattle

Cameras placed in remote Central American forests to track illegal cattle movement recorded multiple wildlife species infected with New World screwworm in recent months, The Guardian reported. The Wildlife Conservation Society released a study documenting the infections. Footage showed jaguars, pumas, tapirs, deer, white-lipped peccaries and porcupines bearing characteristic wounds.

Some infected animals shared water sources with cattle transported across borders without health inspections. Jeremy Radachowsky, director of the Mesoamerica and Caribbean program at the Wildlife Conservation Society, said the cameras provided a unique view of the outbreak's early stages.

“We see infestations in the deepest parts of the interiors of the forest, so now it’s become endemic in wildlife, far from the cattle infestations,” he said.

Screwworm has been confirmed in 34 animals in the United States, mostly in Texas with one case in New Mexico. All detections occurred in livestock or pets; none have been found in U.S. wildlife. The United States is releasing 100 million sterile flies across the southwest and Mexico to slow northward spread.

Eradication would require roughly 500 million flies, according to The Guardian. A sterile-fly breeding facility opened in Mexico in late June; a second facility in Texas is scheduled to open in late 2027. Phillip Kaufman, professor and department head of entomology at Texas A&M University, said current releases fall short of what is needed to push the population south.

“What we lack are sufficient flies in order to start pushing the population back south,” he said. The screwworm crossed the Darién Gap in 2022 and advanced from Nicaragua through Central America in four or five months, following documented illegal cattle routes. Mexico had been free of the pest for about 35 years before its return.