Impact of GSK Biologicals' 2189242A Vaccine on Nasopharyngeal Carriage, Safety and Immunogenicity When Co-administered With Routine EPI Vaccines in Infants Following Safety Assessment in Children Aged 2-4 Years in The Gambia

This study will assess the impact on nasopharyngeal carriage, safety and immunogenicity of GSK Biologicals' pneumococcal vaccine 2189242A given as a 3-dose vaccination course and co-administered with other routine paediatric vaccines in infants in The Gambia. Two formulations containing different doses of pneumococcal antigen and two different schedules will be tested in infants.