The state of Texas is currently facing a significant agricultural challenge with the confirmation of multiple cases of the New World screwworma parasitic fly that was previously eradicated from the United States in the 1960s. This resurgence has prompted a swift and coordinated response from federal and state authorities to contain and eradicate the pest.
The latest developments include three additional confirmed cases in La Salle CountyAndrews Countyand Gillespie Countybringing the total number of detections to five in less than a week. The affected animals include a calf, a dog, and a goat, highlighting the pest’s potential to impact various species.
Understanding the New World screwworm threat
The New World screwworm is a flesh-eating parasite that poses a significant threat to warm-blooded animals, including livestock, wildlife, and pets. Female flies lay their eggs in open wounds or body openings, and when the eggs hatch, the larvae burrow into living tissue, causing severe wounds that can be fatal if left untreated.
While the pest primarily threatens cattle and other livestock, it can also infest wildlife, pets, and, in rare cases, people. The concern is not just the number of infected animals but the potential for the fly to become established and spread rapidly. Texas, being home to the nation’s largest cattle industry, faces significant economic risks if the outbreak is not contained.
Response efforts and containment strategies
The U.S. Department of Agriculture (USDA) and the Texas Animal Health Commission have mobilized 75 personnel to respond on the ground, with additional support focused on diagnostics, logistics, surveillance, and outreach. Quarantine zones have been established around confirmed cases, and trapping and monitoring efforts are being intensified.
One of the primary tools for eradicating screwworm populations is the release of sterile flies, which prevents reproduction. Sterile fly release operations are set to begin this week from Moore Air Base in Edinburg. The United States currently relies on sterile screwworm flies produced in Panama and Mexicowith a new sterile fly production facility under construction in South Texas expected to be operational next year.
Community awareness and preparedness
Despite the heightened response from state and federal officials, awareness on the ground appears limited. When Texas Public Radio visited La Pryorthe town nearest the Zavala County ranch where one of the first Texas screwworm cases was confirmed, some residents had seen reports about screwworm on social media, while others knew little about the pest.
For ranchers in South Texas, the threat feels immediate. Christian Biedenharnwho ranches in La Salle Countyemphasized the need for quick deployment of resources and funding to establish quarantine zones and sterilize the flies. He stated, “We kind of need all-the-above strategies right now.”
Government and public health response
In San Antoniothe city’s Animal Care Services and Metropolitan Health District referred questions about screwworm preparedness and response efforts to state animal health officials. Mayor Gina Ortiz Jones highlighted the importance of investing in public health and agricultural infrastructure, stating, “This is why you invest in things like public health and USDA.”
USDA Secretary Brooke Rollins is scheduled to visit Kerrville for a briefing on the state’s screwworm response at the Knipling-Bushland U.S. Livestock Insects Research Laboratory. Rollins announced that President Donald Trump had appointed John Bellingera San Antonio businessman and Texas A&M Regent, as USDA’s Senior Advisor for New World Screwworm Preparedness.
The USDA is urging livestock and pet owners to watch for draining wounds, maggots, unusual lesions, or signs of discomfort and to report suspected cases immediately to a veterinarian or animal health authorities. The agency assured that the U.S. food supply remains safe as the New World screwworm does not infest meat or other food products, and affected animals would be identified during federal inspection and would not enter the food supply.