Rotaviruses are the most common cause of severe gastroenteritis in infants and young children in both the United States and world-wide. According to the Centers for Disease Control and Prevention (CDC), rotavirus infections account for ~39% of all cases of severe diarrhea world-wide, which results in >600,000 deaths per year. In the United States, rotavirus gastroenteritis accounts for 500,000 physician visits and ~50,000 hospitalizations per year in the US among children less than 5 years of age. The annual cost of rotavirus gastroenteritis in the US is estimated to be $264 MM in direct medical costs and more than $1 B in total costs.