In response to the escalating threat of the New World screwworm—a parasitic fly capable of inflicting severe harm on livestock, wildlife, and, in rare cases, humans—Texas has initiated a comprehensive strategy to prevent the pest’s incursion from Mexico. Governor Greg Abbott has directed the Texas Animal Health Commission (TAHC) and the Texas Parks and Wildlife Department (TPWD) to establish the Texas New World Screwworm Response Team. This joint initiative aims to coordinate preparedness, enhance surveillance, and implement rapid response measures to safeguard the state’s agricultural and ecological resources.
The New World screwworm (Cochliomyia hominivorax) was declared eradicated from the United States in 1966, following a concerted effort involving the release of sterile flies to disrupt the pest’s reproduction cycle. However, recent detections in southern Mexico have raised alarms about a potential resurgence. In November 2024, a confirmed case in Chiapas, Mexico, prompted the U.S. Department of Agriculture (USDA) to suspend imports of live cattle, horses, and bison from Mexico to prevent the parasite’s spread.
Governor Abbott emphasized the state’s readiness to confront the threat, stating, “Texas played a critical role in eradicating this pest from the United States in the 1960s and will do so again if the need arises.” The newly formed response team is tasked with disseminating information to stakeholders, coordinating state preparedness and response efforts, and fostering effective engagement with landowners, livestock producers, and the public.
Dr. Lewis R. “Bud” Dinges, TAHC executive director and state veterinarian, assured Texans of ongoing preparations: “Texans can be assured that staff … .” The response team will leverage resources and expertise from both TAHC and TPWD to ensure a swift and effective reaction should the screwworm breach the state’s borders.
At the federal level, the USDA has unveiled a multi-faceted strategy to combat the screwworm threat. Central to this plan is the establishment of an $8.5 million … fly dispersal facility in Edinburg, Texas, designed to mass-produce sterile male screwworm flies to curb the pest’s reproduction. Additionally, a $21 million investment is allocated for upgrading a sterile fly production facility in Mexico, aiming to produce up to 100 million sterile flies weekly.
These efforts are complemented by strategic trapping at the U.S … the pest’s spread. Monthly assessments by the USDA will guide future import decisions based on containment progress.
The potential reintroduction of the New World screwworm poses significant economic risks to Texas’s livestock industry, valued in the tens of billions of dollars. An outbreak could result in substantial losses, as evidenced by a 2016-2017 infestation in Florida that required $3.2 million to eradicate and led to the death of 15% of the Key deer population.
Beyond economic concerns, the parasite threatens the state’s diverse wildlife and ecological balance. The coordinated response by Texas agencies, in partnership with federal authorities, underscores the commitment to protecting both the state’s economy and its natural heritage.
