Screwworms are fly larvae (maggots) that feed on living flesh. These parasites can infect any warm-blooded animal, including humans. Screwworms can enter wounds as well as body orifices, and feed on living tissue in that area.
On October 3, 2016 USDA announced the confirmation of New World screwworm (Cochliomyia hominivorax) in Key deer from the National Key Deer Refuge in Big Pine Key, Florida. New World screwworm had been eradicated from the United States more than three decades ago, and this was the first infestation in Florida in 50 years.