Anisakiasis From the American Perspective

Human anisakiasis results from accidental infection with larval ascarid nematodes, which normally parasitize several phyla of marine life during their complex life cycle.¹,²Larvae from two genera,Anisakis and Phocanema, of the family Anisakidae, have been definitely identified from human cases, butAnisakishas produced by far the greater number of human cases. Adult worms of these two genera infest the stomachs of marine mammals, attaching and burrowing into the mucosal surface in dense clusters. Unembryonated eggs passed in the stool develop and hatch in sea water to produce sheathed secondstage larvae. After ingestion by a small crustacean, the larva molts and encysts in the crustacean's body cavity. The larval worm then encysts in the viscera or muscles of any fish that eats these parasitized crustaceans. Fish or squid that eat other parasitized fish also become parasitized. During repeated passages from one fish to another, the larvae may grow