Flesh-eating screwworms head for American livestock

Southern states are bracing for a potential invasion of the New World screwworm that could disrupt livestock markets and raise already high meat prices. So far, the parasite has yet to land in the United States, but it has been spreading across Mexico and Central America. Previously eradicated from the United States in the 1960s, the fly can infest livestock, pets, wildlife and in rare cases, humans.