Assessment of Antibody Persistence in Children Previously Vaccinated With Pneumococcal Conjugate Vaccine

Inclusion Criteria: * Male or female between, and including, 28-30 months of age at the time of first blood sampling. * Subjects who previously participated in the 105553 and 107046 studies and who received a full four dose regimen of pneumococcal conjugate vaccine during the primary and booster studies. * Subjects for whom the investigator believes that their parents/guardians can and will comply with the requirements of the protocol. * Written informed consent, covering visits 1, 2 and 3, obtained from the parent or guardian of the subject. * Free of obvious health problems as established by medical history and clinical examination before entering into the study. Exclusion Criteria: * Chronic administration of immunosuppressants or other immune-modifying drugs within 6 months prior to the blood sampling * Administration of any additional pneumococcal vaccine since end of 107046 study. * Use of any investigational or non-registered product (drug or vaccine) within 30 days preceding the blood sampling. * Administration of immunoglobulins and/or any blood products less than 6 months prior to blood sampling. * Any confirmed or suspected immunosuppressive or immunodeficient condition since the end of the 107046 study, based on medical history and physical examination.