Farmers in Texas Mexico use gasoline lime against flesh-eating parasite as 2026 sterilization delay sparks crisis

Farmers and ranchers in Texas and southern Mexico are confronting an alarming resurgence of the New World screwworm, a parasitic fly whose larvae infest open wounds on livestock, leading to severe infections and often death within days. The crisis has intensified so rapidly that desperate measures—such as applying gasoline or lime to wounds—have emerged as makeshift solutions to combat the infestation [1]. The parasite, which had been nearly eradicated in the region through sterile insect techniques decades ago, is now spreading at an alarming rate, forcing agricultural workers to rely on unorthodox methods while awaiting more sustainable interventions.

The New World screwworm’s lifecycle poses a critical threat to cattle, pigs, sheep, and even household pets. Female flies lay eggs in even minor wounds, and the hatching larvae consume tissue to survive. Veterinarians in Chiapas, a Mexican state bordering Guatemala, report a sharp increase in cases over the past month, with some ranchers losing entire herds. Alfredo Chávez, a veterinarian treating infected animals, noted that the lack of government resources has left ranchers to fend for themselves. “We’ve faced it alone,” he stated, highlighting the absence of coordinated support despite previous successes in controlling the parasite through sterile fly programs [1].

The U.S. and Mexico had collaborated to combat earlier outbreaks, with sterile fly releases proving effective in the 1980s and 1990s. However, a new facility in Chiapas designed to produce sterile screwworms for eradication is not expected to be operational until 2026. This delay has left ranchers with limited options. The cost of veterinary treatments has spiked, pushing many to adopt gasoline and lime—a practice that, while temporarily effective, risks damaging tissue and increasing the likelihood of secondary infections. Veterinarians warn that these harsh chemicals can complicate recovery and reduce the market value of treated livestock [1].

The outbreak has also disrupted cross-border trade. In response to a 2025 detection of infected cattle in Veracruz, U.S. authorities temporarily suspended Mexican cattle imports, a move that remains in place despite regional herds being intended for domestic consumption. The economic impact is mounting: ranchers report declining livestock prices and escalating treatment costs, with small-scale producers particularly vulnerable. Edi Valencia Santos, a caretaker in Chiapas, described the situation as a “big, big problem,” noting that the costs of managing infected animals are eroding livelihoods [1].

U.S. and Mexican officials are accelerating plans to deploy sterile male flies to curb the infestation, but the speed of the parasite’s spread has outpaced these efforts. The crisis underscores broader vulnerabilities in regional agricultural systems, where shared ecosystems and trade dependencies require coordinated action. Analysts emphasize the need for sustained investment in pest control programs and cross-border collaboration to prevent future outbreaks. For now, however, farmers remain in a race against time to protect their herds from a parasite that has reemerged with devastating force [1].

[1] [Mexican flesh-eating parasite surged so fast that farmers in Texas, Mexico pour gasoline and lime on open cattle wounds] [https://fortune.com/2025/07/25/us-mexican-breeding-sterile-new-world-screwworm-stop-flesh-eating-parasite-texas/]

[2] [Ranchers in southern Mexico are struggling against a flesh-eating parasite infecting livestock...] [https://www.yahoo.com/news/articles/ranchers-southern-mexico-struggling-against-191709396.html]