A clinical study to determine the safety and efficacy of a new liquid vaccine (ROTAVAC 5C) against childhood diarrhea that is caused by rotavirus

INTERVENTION: Intervention1: ROTAVAC 5C formulation BBIL‐R2014‐1: Single dose administered orally as three doses at 4 (+1) weeks interval. Intervention2: ROTAVAC 5C formulation BBIL‐R2014‐2: Single dose administered orally as three doses at 4 (+1) weeks interval. Control Intervention1: ROTAVAC®: Single dose administered orally as three doses at 4 (+1) weeks interval; antacid buffer (2.5mL/dose sodium bicarbonate citrate) to be administered 5 min prior to the vaccine. CONDITION: Rotavirus Gastroenteritis PRIMARY OUTCOME: Exploratory Phase ; The difference in immunogenicity achieved with two formulations of ROTAVAC 5C will not be statistically significant to that achieved with ROTAVAC®, when administered orally as 3‐dose regimen. ; Safety assessment of ROTAVAC 5C formulations. ; Confirmatory Phase ; Establish lot consistency and immunogenicity in each treatment arm at 4‐6 weeks after administration of 3rd dose in comparison to baseline levels.‐‐‐‐‐‐Timepoint: Exploratory Phase ; Baseline and 4‐6 weeks post 3rd dose. ; Confirmatory Phase ; Baseline, 4‐5 weeks post 2nd dose and 4‐6 weeks post 3rd dose. SECONDARY OUTCOME: Exploratory phase: Evaluation of shedding of rotavirus. ; Confirmatory Phase: Assess 4‐ fold rise in serum anti‐rotavirus IgA titers 4‐6 weeks after administration of 3rd dose in comparison to baseline titers in all groups. ; Assess sero response to childhood vaccines ; Asses vaccine reactogenicity and safety of the two formulations of ROTAVAC 5C and ROTAVAC®. ; ‐‐‐‐‐‐Timepoint: Stool specimen: Day 3 and 7 after each vaccine dose ; Immunogenicity and Sero‐response to childhood vaccines: : Baseline and 4‐6 weeks after 3rd dose ; Safety: Throughout the study period ; INCLUSION CRITERIA: 1.Healthy infants as established by medical history and clinical examination before entering the study. 2.Age: 6‐8 weeks 3.Weight â?¥2.5 kgs at birth. 4.Infants received EPI vaccines (OPV, BCG and Hep B) at birth. 5.Parental ability and willingness to provide informed consent. 6.Parent who intends to remain in the area with the participant during the study period.