• Opsonophagocytic activity against vaccine pneumococcal serotypes. [ Time Frame: One month after the administration of the 3rd vaccine dose. ] [ Designated as safety issue: No ]
• Concentrations of antibodies against vaccine pneumococcal serotypes. [ Time Frame: One month after the administration of the 3rd vaccine dose. ] [ Designated as safety issue: No ]
• Concentrations of antibodies against cross-reactive pneumococcal serotypes. [ Time Frame: One month after the administration of the 3rd vaccine dose. ] [ Designated as safety issue: No ]
• Opsonophagocytic activity against cross-reactive pneumococcal serotypes. [ Time Frame: One month after the administration of the 3rd vaccine dose. ] [ Designated as safety issue: No ]
• Occurrence of solicited local symptoms. [ Time Frame: Within 4 days after each vaccination dose. ] [ Designated as safety issue: Yes ]
• Occurrence of solicited general symptoms. [ Time Frame: Within 4 days after each vaccination dose. ] [ Designated as safety issue: Yes ]
• Occurrence of unsolicited adverse events. [ Time Frame: Within 31 days after each vaccination dose. ] [ Designated as safety issue: Yes ]
• Occurrence of serious adverse events. [ Time Frame: Following the administration of the first dose of study vaccine throughout the entire study period up. ] [ Designated as safety issue: Yes ]

The purpose of this study is to assess the immunogenicity in terms of antibody response and the safety/reactogenicity in terms of solicited and unsolicited symptoms and serious adverse events following primary vaccination of Mexican infants with pneumococcal conjugate vaccine GSK 1024850A co-administered with a diphtheria, tetanus, acellular pertussis (DTPa)-combined vaccine (Infanrix Hexa) and rotavirus vaccine (Rotarix) in children during the first 6 months of age.

The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.

• Biological: Pneumococcal conjugate vaccine GSK1024850A.
• Biological: Infanrix hexa.
• Biological: Rotarix.

Inclusion Criteria:

• Male or female subjects between and including 6-12 weeks of age at the time of the first vaccination.
• Subjects for whom the investigator believes that their parents/guardians can and will comply with the requirements of the protocol.
• Written informed consent 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.
• Born after a gestation period of 36 to 42 weeks inclusive.

Exclusion Criteria:

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine(s) within 30 days preceding the first dose of study vaccine, or planned use during the study period.
• Planned administration/administration of a vaccine not foreseen by the study protocol during the period starting one month before each dose of vaccines and ending 7 days after dose 1 and dose 2 and one month after dose 3.
• 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.
• Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs since birth.
• A family history of congenital or hereditary immunodeficiency.
• Any confirmed or suspected immunosuppressive or immunodeficient condition based on medical history and physical examination.
• Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period.
• Previous vaccination against diphtheria, tetanus, pertussis, polio, hepatitis B, Haemophilus influenzae type b, rotavirus and/or Streptococcus pneumoniae; with the exception of vaccines where the first dose may be given at birth within the first two weeks of life according to national recommendations (e.g. Hepatitis B and BCG).
• History of, or intercurrent, diphtheria, tetanus, pertussis, polio, hepatitis B and Haemophilus influenzae type b disease.
• Gastroenteritis within 7 days preceding the study vaccine administration (warrants deferral of the vaccination).
• Any clinically significant history of chronic gastrointestinal disease including any uncorrected congenital malformation of the gastrointestinal (GI) tract, intussusception (IS) or other medical condition determined to be serious by the investigator.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccines.
• History of any neurological disorders or seizures.
• Major congenital defects or serious chronic illness.
• Acute disease at the time of enrolment.