In the mid‑20th century, ranchers across the southern United States watched livestock being literally eaten alive by a flesh‑eating parasite: New World screwworm. This episode tells the story of how an entomologist’s “absurd” idea helped eradicate screwworm from North America, and why that victory is suddenly back in the spotlight as new cases appear in Texas in 2026. We follow the parasite’s biology, the development of the Sterile Insect Technique, the massive binational infrastructure that kept screwworm at bay until it was gutted last year, and the quiet, ongoing work of prevention that most people never see.

Along the way, we explore what this outbreak can teach us about public health systems, maintenance versus one‑time “wins,” and why some of the most important turning points in infectious disease are really long‑term commitments.

Companion blog post with annotated citations and resources at infectiousdose.com.

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