Ecology and Genetic Structure of Zoonotic Anisakis spp. from Adriatic Commercial Fish Species

Abstract

ABSTRACTConsumption of raw or thermally inadequately treated fishery products represents a public health risk, with the possibility of propagation of liveAnisakislarvae, the causative agent of the zoonotic disease anisakidosis, or anisakiasis. We investigated the population dynamics ofAnisakisspp. in commercially important fish—anchovies (Anisakis), sardines (Sardina pilchardus), European hake (Merluccius merluccius), whiting (Merlangius merlangus), chub mackerel (Scomber japonicus), and Atlantic bluefin tuna (Thunnus thynnus)—captured in the main Adriatic Sea fishing ground. We observed a significant difference in the numbers of parasite larvae (1 to 32) in individual hosts and between species, with most fish showing high or very highAnisakispopulation indices. Phylogenetic analysis confirmed that commercial fish in the Adriatic Sea are parasitized byAnisakis pegreffii(95.95%) andAnisakis simplexsensu stricto(4.05%). The genetic structure ofA. pegreffiiin demersal, pelagic, and top predator hosts was unstructured, and the highest frequency of haplotype sharing (n= 10) was between demersal and pelagic fish.