Diarrhea is a leading cause of childhood mortality in the world, accounting for 5–10 million deaths per year. In early childhood, the single most important cause of severe dehydrating diarrhea is rotavirus infection.
Rotaviruses, which are in the Reoviridae family, cause disease in virtually all mammals and birds. The virus is a wheel-like, triple-shelled icosahedron containing 11 segments of double-stranded RNA. The diameter of the particles by electron microscopy is approximately 80 nm. Rotaviruses are classified by serogroup (A, B, C, D, E, F, and G) and subgroup (I or II).
Occasional human outbreaks of group C rotavirus are reported. The other serogroups infect only nonhumans.
Rotavirus infection is most common in winter months in temperate climates. In the United States, the annual winter peak spreads from west to east
Disease tends to be most severe in patients 3–24 mo of age, although 25% of the cases of severe disease occur after 2 yr of age, with serologic evidence of infection developing in virtually all children by 4–5 yr of age. Infants younger than 3 mo are relatively protected by transplacental antibody and possibly breast-feeding. Infections in neonates and in adults in close contact with infected children are generally asymptomatic
Rotavirus infection typically begins after an incubation period of <48 hr (range 1–7 days) with mild to
moderate fever as well as vomiting followed by the onset of frequent, watery stools. All 3 symptoms are present in about 50–60% of cases. Vomiting and fever typically abate during the 2nd day of illness, but diarrhea often continues for 5–7 days. The stool is without gross blood or white cells. Dehydration may develop and progress rapidly, particularly in infants. The most severe disease typically occurs among children 4–36 mo of age.
Avoiding and treating dehydration are the main goals in treatment of viral enteritis. A secondary goal is maintenance of the nutritional status of the patient.
There is no routine role for antiviral drug treatment of viral gastroenteritis
Therapy with probiotic organisms such as Lactobacillus species has been shown to be helpful only in mild cases and not in dehydrating disease.