To provide specific data on immunogenicity of GSK Biologicals' HRV liquid vaccine, when co-administered with the routine Expanded Program of Immunization (EPI) in Vietnam. The study will also assess reactogenicity and safety of the HRV liquid vaccine relative to the placebo

Inclusion Criteria:

• Healthy male or female infant between, and including, 6 and 10 weeks of age with a birth weight of > 2000 grams.
• Written informed consent obtained from the parent or guardian of the subject.

Exclusion Criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the HRV liquid vaccine or placebo within 30 days preceding the first dose of HRV liquid vaccine or placebo, or planned use during the study period.
• Chronic administration of immunosuppressants or other immune-modifying drugs since birth.
• Planned administration/ administration of a vaccines not foreseen by the study protocol except for DTPw, HBV and OPV vaccines within 14 days before each dose of HRV liquid vaccine or placebo and ending 14 days after.
• Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product (pharmaceutical product or device).
• History of allergic disease or reactions likely to be exacerbated by any component of the HRV liquid vaccine or placebo.

Patient-level data for this study will be made available through www.clinicalstudydatarequest.com following the timelines and process described on this site.