The epidemiology of rotavirus infections: a global perspective.

Rotavirus, which is the most common cause of infantile diarrhea worldwide, mainly affects infants between the ages of 6 and 24 months. Most infections in human newborns are mild or asymptomatic, due to the inherently attenuated nature of the "nursery" rotavirus strains. Adults are also sometimes affected, especially those in families with an infected child; the disease also occurs in closed adult communities. HIV-infected persons, travelers, or as a result of water-borne epidemics. Nosocomially acquired hospital infections add to morbidity and to the cost of hospitalization. A winter predominance of rotavirus diarrhea has been noted in temperate climates but not in tropical areas. Group A rotavirus infections are generally more common, but human infections with groups B and C have also been documented. The prevalence of serum antibodies is high during the neonatal period, but it declines sharply between the ages of 3 and 6 months, then rises steeply, peaking at approximately 2 years and remaining high into adulthood. Vaccines against rotavirus are currently under evaluation.