Monovalent H5N1 Vaccine GSK1557484A in Children 6 Months to < 18 Years of Age

Inclusion Criteria

• A male or female child >= 6 months and = 38.0ºC by any method, or acute symptoms greater than "mild" severity on the scheduled date of first dose.
• Diagnosed with cancer, or treatment for cancer, within 3 years.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• Receipt of systemic glucocorticoids within 1 month prior to first dose of test article or any other cytotoxic or immunosuppressive drug within 6 months prior to first dose of test article. Receipt of any immunoglobulins and/or any blood products within 3 months of first test article administration or planned administration of any of these products during the study period.
• Any significant disorder of coagulation or treatment with warfarin derivatives or heparin.
• An acute evolving neurological disorder or history of Guillain-Barré syndrome within 6 weeks of receipt of seasonal influenza vaccine.
• Administration of an inactivated seasonal influenza vaccine within 14 days, or of a live, attenuated seasonal influenza vaccine within 30 days before the first test article dose, or of any other vaccine(s) not foreseen by the study protocol within 30 days before the first test article dose.
• Planned administration of any vaccine(s) not foreseen by the study protocol through completion of the "Day 42" visit.
• Any known or suspected allergy to any constituent of influenza vaccines or history of severe reaction to any previous influenza vaccination.
• Known pregnancy, or a positive urine pregnancy test result prior to each test article dose.
• Lactating or nursing.
• Child in care.