The US Department of Agriculture has confirmed the first detection of the New World screwworm, a parasite that devours living tissue, in US wildlife. An elk in Pecos County, Texas, tested positive for the infestation after being harvested by a hunter, federal officials announced on Wednesday. The discovery prompts immediate action from state and federal agencies to contain the spread and protect both wildlife and livestock populations across the region.
Alert Zone Expanded in Texas
The Texas Animal Health Commission is revising the boundaries of its previously designated infested zone in response to the elk finding. This adjustment reflects growing concerns over the parasite’s northward movement from Central America via Mexico. The USDA, in conjunction with the Texas Parks and Wildlife Department, has launched enhanced surveillance efforts to monitor wildlife health in the affected area. “We encourage all hunters and landowners to be vigilant for signs of New World screwworm while they are out in the field this season,” said Alan Cain, director of Texas wildlife division.
A Parasite of Concern for Livestock and Consumers
Once eradicated from the United States decades ago, the New World screwworm has resurfaced in recent months, triggering significant economic and agricultural repercussions. In June, a calf in Zavala County, near the US-Mexico border, was also found to be infected. Since then, additional cases have been reported on a horse and a dog, underscoring the parasite’s ability to affect multiple species. In response, the federal government imposed a ban on Mexican cattle imports last year to prevent further spread. Beef supply chains were disrupted, driving prices to unprecedented levels for American consumers. Trade with Mexico resumed in August under a controlled, phased re-entry plan, but the threat remains acute.
Public urged to report suspicious symptoms
Health officials are urging outdoor workers, hunters, and pet owners to watch for telltale signs of screwworm infestation, including hair loss, open wounds, and lesions that emit a foul odor. Early detection and treatment are critical to preventing transmission. Anyone who encounters symptoms consistent with myiasis should contact local veterinary or health authorities immediately. Reporting helps containment teams respond swiftly and effectively.
Why it Matters
The return of the New World screwworm to US soil highlights vulnerabilities in biological surveillance and the cascading effects of cross-border animal health threats. Beyond the immediate risk to wildlife and livestock, the parasite’s presence threatens food security and rural livelihoods, particularly as it intersects with trade policies and consumer prices. With the parasite now established in parts of Texas, swift coordination between agencies and the public will determine how widely it spreads—and what the ultimate economic and ecological cost may be.
