Immunogenicity Study of Antibody Persistence and Booster Effect of DTaP-HB PRP~T Combined Vaccine in Filipino Infants

DTaP-HB-PRP\~T combined vaccine is being developed in order to comply with expanding programs for immunization in infancy, while offering the benefit of a reduced number of injections, and potentially of an increased acceptance. Primary Objectives: * To describe the antibody persistence at 12 to 18 months following a three-dose primary series vaccination of either DTaP-HB-PRP\~T or Tritanrix-Hep B/Hib™ given at 6, 10 and 14 weeks of age, and one dose of Hepatitis B (Hep B) vaccine given at birth. * To describe the effect of a booster dose of DTaP-HB-PRP\~T on immunogenicity at 12 to 18 months following a three-dose primary series vaccination of either DTaP-HB-PRP\~T or Tritanrix HepB/Hib™ given at 6, 10 and 14 weeks of age, and one dose of Hep B vaccine given at birth. Secondary Objective: * To describe the safety profile of the booster dose of the DTaP-HB-PRP\~T vaccine when administered concomitantly with Oral Polio Vaccine (OPV).