Fast Five Quiz: How Much Do You Know About Common Conditions Associated With Diarrhea?

Jamie Shalkow, MD; Felipe Sarlat


August 07, 2018

Most cases of acute infectious gastroenteritis are viral. Rotavirus is the most common etiologic agent of healthcare-acquired diarrhea in pediatric patients. Community- and healthcare-acquired infections have similar temporal distributions, are caused by the same viral subtypes, and affect children of the same age groups. In one study, all of the healthcare-acquired infections with known viral subtypes occurred while the same subtype was still active in the community, suggesting that healthcare-acquired infections arise from repeated introduction of the community-acquired rotavirus into the hospital setting.

Group A rotavirus causes 25% to 65% of severe infantile gastroenteritis worldwide. Acute infections with group C are quite frequent in the United States and worldwide. After rotavirus, Cryptosporidium, Shigella, and enterotoxigenic Escherichia coli are also important pathogens.

In adults, Norovirus is the most common etiologic agent of viral gastroenteritis and the second most common cause of hospitalization for acute gastroenteritis. Other common viral pathogens include rotavirus, enteric adenovirus, and astrovirus. Most cases of epidemic viral gastroenteritis in adults and children are caused by the caliciviruses. Some examples include Norovirus, which is the most common viral cause of epidemic gastroenteritis, and sapovirus, which sometimes are referred to as genogroup III, although they are not like Norwalk (eg, Sapporo, Parkville, Manchester, Houston, London).

Acute viral gastroenteritis occurs throughout life. Severe cases are seen in the very young and the elderly. The etiology also varies with age. In infants, most cases are due to rotavirus; in adults, the most common cause is norovirus.

For more on the etiology and epidemiology of viral gastroenteritis, read here.


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