Vaccination with Rotarix will continue from study initiation through June 30, 2011. Surveillance for rotavirus gastroenteritis will occur at Matlab Diarrhoeal Hospital and the community treatment centres of the Matlab HDSS continuously throughout the study period. Diarrheal illness information collected through surveillance will be linked to Rotarix study-specific data through the subject's HDSS identification numbers. The primary study endpoint will be the occurrence of an illness episode of acute diarrhoea, among infants and children admitted to a medical facility, determined to be caused by wild-type rotavirus found in a stool specimen. At the end of the surveillance period, rates of this primary study endpoint among age-eligible infants will be compared for villages randomized to receive Rotarix versus for villages randomized not to receive Rotarix. We expect that the rates of rotavirus diarrhoea will be significantly lower among children from the vaccinated villages.