QOD

Which one of the following types of viruses is the leading cause of epidemics of gastroenteritis?

A.
Adenoviruses.
B.
Noroviruses.
C.
Norwalk viruses.
D.
Rotaviruses


The Norwalk agent was the first virus that was identified as causing gastroenteritis in humans, but recognition of its importance as a pathogen has been limited because of the lack of available, sensitive, and routine diagnostic methods. Recent advances in understanding the molecular biology of the noroviruses, coupled with applications of novel diagnostic techniques, have radically altered our appreciation of their impact. Noroviruses are now recognized as being the leading cause of epidemics of gastroenteritis and an important cause of sporadic gastroenteritis in both children and adults. Although norovirus gastroenteritis is generally mild and of short duration, new evidence suggests that the illness can be severe and sometimes fatal, especially among vulnerable populations — young children and the elderly — and is a common cause of hospitalization for gastroenteritis. Routine diagnostic methods are still unavailable to most clinicians, but epidemiologic studies have identified both rapid local transmission and the emergence of novel norovirus strains that spread in a global fashion, similar to the epochal patterns of influenza. Controlling outbreaks of norovirus poses major challenges.

Answer: B