The leading cause of gastroenteritis, food-borne viral infections are primarily due to two main viruses : norovirus which causes gastroenteritis and Hepatitis A virus which causes hepatitis A. Human excrete the viruses (feco-oral route)  and food  contamination occurs either from an infected food handler during preparation (GHP), from contaminated water (GAP), typically during primary production. Symptoms are typically nausea, vomiting, diarrhoea and abdominal pain. Viral food-borne outbreaks  are mostly caused by Norovirus.

What are enteric viruses?

Viruses are infectious microorganisms, with DNA or RNA genome enclosed in a protein coat. Unlike bacteria, viruses can only multiply inside living cells of other organisms. Many viruses resist to stresses such as heat, drying, freezing, UV light, High Pressure  and survive for long periods of time in foods or the environment. 

What are the most frequent viruses in viral outbreak ?

The majority of viral foodborne illnesses are caused by those viruses : Norovirus Gi & Norovirus GII, Hepatitis A virus and Hepatitis E virus, Rotavirus (for Children), but not limited to them. Enterovirus, Sapovirus, Astrovirus are also described in the scientific literature.

Foods associated with viral food-borne illnesses 

Food associated with viral food-borne illnesses are bivalve Shellfish (Oysters, mussels, cockles, scallops, etc), Fruits (strawberries, raspberries, goji berries, dates, tomatoes, etc), vegetables in the form of leafy greens (spinach, lettuce, herbs, etc), pork and game meat (figatellu, etc), Ready-to-eat.
 

Detection of Viruses in Food and Environmental Samples?

Viruses cannot be cultured, unlike bacteria. Enrichment is not possible. Molecular techniques are the methods of choice for the detection,  identification and quantification of foodborne viruses. The ISO/TS 15216-1&2 Standard covers most pre-treatment steps to elute viruses from the different matrices, specifically for Norovirus and hepatitis A Virus.