Larvae of Sulcascaris sulcata (Nematoda: Anisakidae), a parasite of sea turtles, infect the edible purple dye murex Bolinus brandaris in the Tyrrhenian Sea

Abstract

Anisakid nematodes are among the most common helminth parasites of the marine realm, particularly important for their implications with human infections and/or allergies. Members of the Anisakidae use aquatic mammals, birds and fish as definitive hosts, and crustaceans, fish and molluscs as intermediate/paratenic hosts. Sulcascaris sulcata, the only species in the monotypic genus Sulcascaris, represents the exception being a parasite of sea turtles as adult. The recent findings of larvae of S. sulcata in scallops (Pecten jacobeus and Aequipecten opercularis) and Mediterranean mussels Mytilus galloprovincialis intended for human consumption from the Mediterranean Sea caused concern regarding the sanitary control of edible molluscs and consumer safety. Herein, we investigated the larval anisakids collected from the purple dye murex, Bolinus brandaris, harvested for human consumption from the Central Mediterranean Sea (Tyrrhenian Sea). Morphological study and sequence analysis of the internal transcribed spacer regions of the ribosomal DNA and the mitochondrial cytochrome c oxidase subunit 2 gene locus revealed the occurrence of fourth stage larvae of S. sulcata in 16% of the purple dye murex examined. The present study adds the purple dye murex to the list of the known intermediate hosts of this parasite in the Mediterranean Sea and the northern coast of Campania region as site where individuals of loggerhead turtle and purple dye murex may become infected. This is the first study reporting an anisakid nematode in edible gastropods. Epidemiological features of infection in the purple dye murex and implications for gastropod safety and risk for consumers are discussed.