Noroviruses: a global cause of acute gastroenteritis.

Norwalk virus, the prototype norovirus, was identified in 1972 by the late Albert Kapikian in a fecal sample from an outbreak of acute gastroenteritis at an elementary school in Norwalk, Ohio, USA. During this outbreak, almost 50% of the students and teachers were infected during 2 days, highlighting the rapid spread of norovirus outbreaks. The advent and wide availability of molecular diagnostic techniques has resulted in increased awareness of the importance of norovirus-associated acute gastroenteritis.