An overview of 20 years of studies on the prevalence of human enteric viruses in shellfish from Galicia, Spain.

Summary Galicia (NW Spain) has 1,490 km of coastline, and its particular topography, characterized by the presence of fiord-like inlets, called rias, with an important primary production, make this region very favourable for shellfish growth and culture. In fact, Galicia is one of the most important mussel producers in the world. Due to the proximity to cities and villages, and the anthropogenic activities in these estuaries, and despite the routinely official controls of the bivalve harvesting areas, contamination with material of faecal origin is sometimes possible but, whereas current regulation based on Escherichia coli as indicator microorganism has been revealed as useful for bacterial contaminants, this is not the case for enteric viruses. The aim of this review is to offer a picture on the situation of different harvesting areas in Galicia from a virological standpoint. A recompilation of results obtained in the last 20 years is presented, including not only the data for the well known agents norovirus (NoV) and hepatitis A virus (HAV), but also data on emerging viral hazards, including sapovirus (SaV), hepatitis E virus (HEV) and aichivirus (AiV). Epidemiological differences related to diverse characteristics of the harvesting areas, viral genotype distribution, or epidemiological links between environmental and clinical strains will be also presented and discussed. The presentation of these historical data all together could be useful for future decisions by competent authorities for a better management of shellfish growing areas. This article is protected by copyright. All rights reserved.