A case of New World screwworm has been reported in a Texas calf, marking the return of the parasite to the United States. The screwworm, which incubates in the wounds or orifices of warm-blooded animals, had previously been eradicated in North and Central America through a decades-long program of fly sterilization led by the United States.

Causes of the Outbreak

Ecologist Jeremy Radachowsky attributes the resurgence of the screwworm to illegal cattle smuggling, which has allowed the parasite to spread quickly across southern Mexico and into the United States. The USDA and the Mexican Agriculture Department have announced new efforts to breed and release sterilized flies to combat the outbreak.

Texas Agriculture Commissioner Sid Miller has criticized the US response to the outbreak, calling for the use of the Screwworm Adult Suppression System (SWASS), a type of pesticide and bait. However, the USDA has pushed back on Miller’s claims, citing environmental concerns and the potential harm to sterile flies.

Consequences of the Outbreak

The screwworm outbreak poses a significant threat to the beef industry in the southwestern United States, with the potential to cause billions of dollars in damage. The parasite can also infect humans, although it is not typically transmitted from person to person.

The USDA has closed southern border ports to livestock from Mexico to prevent the spread of the screwworm. However, the parasite has already been detected in New Mexico, and experts warn that it could continue to spread unless measures are taken to stop it at the source.

Original reporting: KEYT (Ventura/Santa Barbara) — read the source article.