ABSTRACT
Human noroviruses (HNoVs) are recognized worldwide as the most common viral causative agents of food- and waterborne gastroenteritis. Since the first description of a virus associated with a human diarrheal outbreak in 1972, in a school in Norwalk, Ohio, 1 which was then called “Norwalk-like” virus, HNoVs have been reported as causal agents in many diarrheal outbreaks. Despite their frequent involvement in epidemic outbreaks, their true incidence has been challenging to estimate. This may be attributed to the technical limitations in diagnostic methods, and also to the mild and self-limiting nature of the disease. In fact, HNoV symptoms and cases are often not reported to public authorities since they rarely require medical care or hospitalization, apart from those involving the elderly or immunocompromised. 2,3
