Norovirus in bivalve molluscs: development of a Real Time RT PCR protocol and its application for a viral contamination monitoring and for a bioaccumulation study

The Food Hygiene Package is a body of European Regulations laying down hygiene rules for foodstuffs produced in the EU and non-EU countries exporting to the EU. The pursuit of a high level of protection of human life and health is one of the fundamental objectives of this laws package. Some points of EC Regulations undergo to critical review by the Commission, and particular attention was given to fishery products. Commission Regulation (EC) No 2073/2005 of 15 November 2005 on microbiological criteria for foodstuffs, in Annex I, Chapter 1, lays down the food safety criteria for live bivalve molluscs and live echinoderms, tunicates and gastropods and sets sampling-plans, limits and analytical reference methods only concerning bacterial micro-organisms of Salmonella spp. and Escherichia coli genera. Epidemiological data of the last years reported the consumption of live bivalve shellfish infected by enteric viruses as common cause of human gastroenteritis. Norovirus resulted the leading cause of all human gastroenteritis outbreaks worldwide. For this reason, in the first part of Reg. (EC) No 2073/2005, in the whereas at point 12, it’s written that the Scientific Committee on Veterinary Measures relating to Public Health (SCVPH) issued an opinion on Norwalk-like viruses (NLVs, noroviruses) on 30-31 January 2002. In that opinion it concluded that the conventional fecal indicators are unreliable for demonstrating the presence or absence of NLVs and that the reliance on fecal bacterial indicator removal for determining shellfish purification times is unsafe practice. So Salmonella and Escherichia coli can not be used as only indicators of safety criteria in live bivalve molluscs. In particular, at following points we can read that it may be necessary to set harmonized sampling frequencies at Community level, particularly in order to ensure the same level of controls to be performed throughout the Community. Finally it’s confirmed that criteria for pathogenic viruses in live bivalve molluscs should be established when ...