The Fall and Rise of Screwworm
5 hours ago
- #agricultural-pest-control
- #screwworm-eradication
- #sterile-male-technique
- Screwworm, a flesh-eating parasite, was recently detected in Texas and New Mexico in 2024, marking its first significant US infestation since the 1980s after breaching the containment barrier in Panama.
- Historically, screwworm caused severe livestock losses and economic damage in the US, with millions of infections and deaths annually until eradication efforts began in the mid-20th century.
- The sterile male technique, developed by entomologists Edward Knipling and Raymond Bushland, uses radiation-sterilized male flies to outcompete wild males, leading to population collapse, and successfully eradicated screwworm from the US, Mexico, and Central America.
- A barrier at the Darien Gap between Panama and Colombia, maintained since the early 2000s by dropping millions of sterile flies weekly, failed around 2023 due to factors like COVID-19 disruptions, illegal cattle trafficking, and deforestation.
- Reinfestation has spread rapidly through Central America and Mexico, with thousands of cases, prompting renewed USDA efforts including new production facilities and funding to re-eradicate the parasite, a process expected to take nearly a decade.