80,000 Hours

Eradicating Flesh-Eating Screwworms with Gene Drives – Kevin Esvelt, MIT

The video discusses using gene‑drive technology to eliminate the New World screwworm (Cochliomyia hominivorax), a botfly whose larvae devour the flesh of mammals and birds, causing immense suffering and economic loss. Current control relies on releasing sterile screwworm flies along the Panama border, which prevents reinvasion of North America but cannot eradicate the massive South American populations. The speaker notes that Uruguay loses roughly 0.1% of its GDP to the pest, and estimates that a quadrillion warm‑blooded animals are killed each year. He contrasts this impact with factory‑farming mortality, arguing that even a century of continued intensive animal production would kill far fewer animals than the screwworm does naturally. The speaker emphasizes the ethical dimension, suggesting that eradicating the pest would deliver greater animal‑well‑being benefits than ending factory farming. If gene drives can safely suppress or eliminate the screwworm, the result could be a dramatic reduction in animal suffering, lower economic losses for affected countries, and a proof‑of‑concept for tackling other invasive pests through genetic engineering.