Vaccinating infants against rotavirus can also prevent serious diseases in unvaccinated older children and adults, a new study in The Journal of Infectious Diseases says. Rotavirus or rotavirus gastroenteritis causes severe diarrhea, fever and vomiting and can lead to severe dehydration especially in infants. A vaccine was introduced in the United States in 2008 and the study by the Centers for Disease Control and Prevention (CDC) published online says the vaccination of infants helps reduce rotavirus-related hospital costs in older groups as well.