I'm not familiar with screwworms but apparently they are as nasty as they sound (pdf):Screwworms are fly larvae (maggots) that feed on living flesh. These parasites infest all mammals and, rarely, birds.[...]Female flies lay their eggs at the edges of wounds or on mucous membranes. When they hatch, the larvae enter the body, grow and … Continue reading You Learn Something New Every Day, Screwworm Edition