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Epidemiology and pathogenesis of viral gastroenteritis in adults

Neil R Blacklow, MD
Section Editor
Martin S Hirsch, MD
Deputy Editor
Elinor L Baron, MD, DTMH


Viral gastroenteritis is a common illness that occurs worldwide [1]. There are four medically important causes of viral gastroenteritis: rotavirus, norovirus, enteric adenovirus, and astrovirus (table 1).

In resource-limited settings, viral gastroenteritis is associated with considerable mortality. Rotavirus infection is estimated to cause more than 500,000 deaths per year, which is approximately one-quarter of all deaths due to infectious diarrhea [2,3].

In the United States, viral gastroenteritis causes a few hundred deaths per year, principally due to rotavirus and norovirus [4-7]. However, morbidity is considerable, with approximately 65,000 hospitalizations annually due to norovirus [8].

The epidemiology and pathogenesis of viral gastroenteritis will be reviewed here. The clinical manifestations, diagnosis, treatment, and prevention of these infections are discussed separately. (See "Clinical manifestations and diagnosis of noroviruses and related viruses" and "Clinical manifestations and diagnosis of rotavirus infection" and "Acute viral gastroenteritis in adults".)


There are four medically important causes of viral gastroenteritis: rotavirus, norovirus, enteric adenovirus, and astrovirus (table 1).


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