US detects Barren Worm in Texas, prompting Mexico to halt live cattle imports

The United States Department of Agriculture confirmed a case of the bovine screwworm (Cochliomyia hominivorax) in a calf from Zavala County, Texas, and subsequently in New Mexico. The parasite, eradicated decades ago by a massive sterile‑fly program, lays eggs in open wounds of warm‑blooded animals, causing severe tissue damage.

In response, Mexico's National Service for Agro‑Alimentary Health and Safety (SENASICA) temporarily suspended the import of live cattle and other livestock from the United States to protect disease‑free states such as Chihuahua, Baja California, Sinaloa and others. The measure follows a joint technical assessment by US and Mexican authorities after the Texas detection.

Experts link the re‑emergence to illegal cattle smuggling by organized crime groups moving livestock across Central America without sanitary checks. Wildlife‑conservationist Jeremy Radachowsky warned that “each cow moved illegally can carry the screwworm and other diseases,” adding that “the possibility of avian flu and tuberculosis transmission is also alarming.” Texas Agriculture Commissioner Sid Miller urged the USDA to resume use of the Sterile Adult Release System (SWASS). The outbreak threatens billions of dollars in losses for the southwestern US beef industry.