Safety of GSK Biologicals' Infanrix-IPV+HibTM Vaccine in Healthy Vietnamese Toddlers

Inclusion Criteria: * Subjects who the investigator believes that parent(s)/Legally Acceptable Representative(s) \[LAR(s)\] can and will comply with the requirements of the protocol. * A male or female between, and including, 12 and 24 months of age at the time of vaccination. * Written informed consent obtained from the parent(s)/LAR(s) of the subject. * Healthy subjects as established by medical history and clinical examination before entering into the study. * Subjects who were primed with three doses of a DTP and polio vaccine in the first 6 months of life, and who have received the last dose of the primary vaccination at least six months before the receipt of study vaccine. Exclusion Criteria: * Child in care. * Use of any investigational or non-registered product other than the study vaccine within 30 days preceding the dose of study vaccine, or planned use during the study period. * Administration of a vaccine not foreseen by the study protocol, within 30 days prior to the first study visit, or planned administration during the study period. * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination. * 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. * Evidence of previous or intercurrent booster vaccination against diphtheria, tetanus, pertussis, poliomyelitis and/or Hib disease or vaccination. * History of any neurological disorders or seizures. * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine. * Major congenital defects or serious chronic illness. * Acute disease and/or fever at the time of enrolment. * Administration of immunoglobulins and/or any blood products within the three months preceding vaccination or planned administration during the study period.