• Immune response for Prevnar following vaccination in both the Havrix + Prevnar group and the Prevnar followed by Havrix group.
• Immune response for Havrix following the first dose of Havrix in all groups. The other secondary outcome measure is safety of the study vaccines.

This is a study to evaluate the immunogenicity and safety of GSK Biologicals 2-dose inactivated hepatitis A vaccine when administered with a pneumococcal conjugate vaccine in children as young as 15 months of age

An open, controlled comparison of Havrix administered alone or with Prevnar. The three groups evaluated are: 1) Havrix alone, 2) Havrix plus Prevnar and 3) Prevnar followed by Havrix one month later.

Inclusion Criteria:

• A male or female child 12 or 13 months of age at the time of entry into the Enrollment Phase,
• Free of obvious health problems,
• Subjects must have previously received three doses of Prevnar in his/her first year of life.

Exclusion Criteria:

• Use of any investigational or non-registered drug or vaccine within 42 days preceding the first dose of study vaccine, or planned use during the study period,
• Chronic administration of immuno-suppressant or other immune-modifying drugs within six months prior to vaccination or planned administration at any time during the study period. (For corticosteroids, this will mean prednisone, or equivalent, less than 0.5 mg/kg/day. Inhaled, nasal and topical steroids are allowed.),
• Administration of the ACIP-recommended fourth dose of Prevnar prior to entering the Enrollment Phase of the study,
• Planned administration or administration of any vaccine not foreseen by the study protocol within the period of 42 days before and 30 days after each dose of study vaccine(s),
• Previous vaccination against hepatitis A,
• History of hepatitis A or known exposure to hepatitis A,
• Any confirmed or suspected immunosuppressive or immunodeficient condition, including human immunodeficiency virus (HIV) infection,
• A family history of congenital, hereditary or infectious immunodeficiency or parental risk factors for HIV infection,
• History of allergic disease/reactions or hypersensitivity likely to be exacerbated by any component of Havrix (e.g., neomycin, 2-phenoxyethanol) or Prevnar (e.g., diphtheria toxoid),
• Major congenital defects or serious chronic illness,
• History of any neurologic disorder (history of febrile seizures not associated with an underlying neurological disorder does not exclude the subject),
• Acute disease, defined as the presence of a moderate or severe illness with or without fever, at the time of vaccination,
• Administration of immunoglobulins and/or any blood products within three months prior to the first dose of study vaccine or planned administration at any time during the entire study period.