Nearly every child will experience rotavirus infection before the age of 5. Rotavirus is transmitted via a fecal-oral route. Because the virus is shed in the stool, outbreaks of rotavirus infection can occur on the pediatric hospital wards and in day care centers. Ingestion of the rotavirus particles infects the cells in the villi of the small intestine. Copious amounts of watery diarrhea will occur after an incubation period of 1 to 2 days. If untreated, children less than 2 years of age can die from the resulting severe gastroenteritis dehydration. In the United States, rotavirus infection peaks during the winter months and is the cause of most cases of diarrhea in infants and young children. Rotavirus infection accounts for approximately 70,000 hospital admissions for diarrhea and as many as 100 deaths each year in the United States. World wide rotavirus infection accounts for approximately 1 million deaths each year (Bass, 1996). Although the number of deaths from rotaviral disease in the United States is low, parents frequently miss work, have to arrange for alternative care, travel to the doctor, give their child oral rehydrating solutions, and buy extra diapers. Implementation of mass vaccination with RotaShield will significantly reduce these indirect costs.