Rotavirus is a segmented, double-stranded RNA virus that infects nearly all children worldwide by 3-5 years of age; adults can become infected if exposed.

• Reinfections are progressively less severe.
• Large quantities of virus are shed in the stool during the first week of infection, and transmission takes place both via the fecal-oral route and from person to person.
• Disease incidence peaks in the cooler fall and winter months.