MOLLUSCAN SHELLFISH CONTAMINATION BY ENTERIC VIRUSES: USEFULNESS OF THE LEGAL STANDARDS AND INDICATOR MICROORGANISMS

Abstract
Illness outbreaks caused by enteric viruses after mollusc consumption are an important public health hazard worldwide. The virus responsible for those outbreaks are mainly Norovirus (Norwalk virus group), highly prevalent throughout the world, and the hepatitis A virus, due to the severity of the disease it causes. Though effective to reduce bacterial contamination, depuration techniques for molluscan shellfish, do not wholly eliminate the viral particles. On the other hand, evidence has lately been obtained on the relevance of international trade operations involving fresh or semipocessed molluscs in the transmission of viral diseases among distant geographic areas. Sanitary controls included in the current legislation are based on the number of fecal coliforms, although this bacterial group has been described as a bad indicator of viral contamination and, therefore, its effectivity in preventing the appearance of disease outbreaks is limited. All these data indicate the necessity to include parameters of viral contamination in the sanitary control of molluscan shellfish, either obtained in local production or through imports from third countries.

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