Rotavirus Gastroenteritis

Rotavirus is a double-stranded RNA virus in the Reoviridae family. It infects mature enterocytes lining the villi of the small intestine. These cells normally absorb water, sodium, glucose, and nutrients; when they are damaged or shed, absorptive capacity falls. The result is large-volume, isotonic watery diarrhea and rapid loss of circulating fluid. The usual pattern is abrupt fever and vomiting followed 1–2 days later by profuse diarrhea. Diarrhea generally continues for 3–8 days, although appetite and bowel habits may take longer to normalize. Children 4–24 months old are especially vulnerable because they have a relatively small fluid reserve and depend on caregivers to replace each loss. The immediate danger is not the virus invading the bloodstream. It is the cumulative loss of water and electrolytes through stool and emesis. A child can deteriorate quickly even when the abdomen is soft and the diarrhea itself appears uncomplicated.