Texas officials identified a New World screwworm fly larva in a three-week-old calf [1] in Zavala County.

The detection marks the first case of the parasite in the U.S. in decades [2]. Because the parasite targets livestock, it represents a significant threat to the state's agricultural economy and animal health, though officials said it does not impact human food safety.

Governor Greg Abbott and representatives from the Texas Department of Agriculture and the Texas Animal Health Commission addressed the discovery. They said the parasite is not a food-safety issue and is not transmissible to humans like a virus [1]. The larva was found in a calf located near the U.S.-Mexico border [3].

While the parasite is often described as "flesh-eating," officials said this name is misleading. The screwworm does not enter the human food chain and does not affect people [1]. The primary concern remains the health of livestock, as the larvae can cause severe tissue damage to animals.

This discovery is particularly concerning given the history of the pest in the region. The New World screwworm was declared eradicated from Texas in the 1960s [3]. The current case suggests the parasite has crossed the border from Mexico [4].

State and federal agencies are coordinating to slow the spread of the pest. Texas officials said the situation is being managed as a livestock-health issue rather than a public health crisis [1]. Efforts to contain the parasite involve monitoring livestock, and implementing control measures in the affected border region to prevent a wider outbreak among cattle and other animals.

“The parasite is not a food-safety issue and is not transmissible like a virus.”

The re-emergence of the New World screwworm in Texas after decades of eradication highlights the ongoing challenge of biosecurity at the U.S.-Mexico border. While the lack of risk to human health prevents a general public panic, the potential for widespread livestock infection could lead to significant economic losses for ranchers and trigger stricter agricultural trade regulations.