On September 30, 2016, the US National Veterinary Services Laboratory confirmed an autochthonous case of New World screwworm infestation in a Key deer (Odocoileus virginianus clavium) from Big Pine Key, Fla. This case marked the first identification of a sustained and reproducing population of New World screwworm flies in the United States since 1966. Multiple federal, state, and local government agencies collaborated to initiate a response to the outbreak. Efforts were successful in eradicating the flies from Florida.