Safety Trial of Monovalent Whole Virus Influenza (H1N1) Vaccine

Inclusion Criteria:

• Male or female adult 18 (age of legal consent in Vietnam) through 40 years of age at the enrollment visit.
• Literate and willing to provide written informed consent.
• Free of obvious health problems, as established by the medical history and screening evaluations, including physical examination.
• Capable and willing to complete diary cards and willing to return for all follow-up visits
• For females, willing to utilize reliable birth control measures (intrauterine device, birth control pills, condoms) through the Day 42 visit.

Exclusion Criteria:

• Participation in another clinical trial involving any therapy within the previous three months or planned enrollment in such a trial during the period of this study.
• Receipt of any non-study vaccine within four weeks prior to enrollment or refusal to postpone receipt of such vaccines until after the Day 42 visit.
• Current or recent (within two weeks of enrollment) acute illness with or without fever.
• Receipt of immune globulin or other blood products within three months prior to study enrollment or planned receipt of such products prior to the Day 42 visit.
• Chronic administration (defined as more than 14 consecutively-prescribed days) of immunosuppressants or other immune-modulating therapy within six months prior to study enrollment. (For corticosteroids, this means prednisone or equivalent, >=0.5 mg per kg per day; topical steroids are allowed.)
• History of asthma.
• Hypersensitivity after previous administration of any vaccine.
• Other AE following immunization, at least possibly related to previous receipt of any vaccine.
• Suspected or known hypersensitivity to any of the study vaccine components, including chicken or egg protein.
• Known hypersensitivities (allergies) to food or the natural environment.
• Acute or chronic clinically significant pulmonary, cardiovascular, hepatic, metabolic, neurologic, psychiatric or renal functional abnormality, as determined by medical history, physical examination or clinical laboratory screening tests, which in the opinion of the investigator, might interfere with the study objectives..
• History of leukemia or any other blood or solid organ cancer.
• History of thrombocytopenic purpura or known bleeding disorder.
• History of seizures.
• Known or suspected immunosuppressed or immunodeficient condition of any kind, including HIV infection.
• Known chronic HBV or HCV infection.
• Known active tuberculosis or symptoms of active tuberculosis, regardless of cause.
• History of chronic alcohol abuse and/or illegal drug use.
• Pregnancy or lactation. (A negative pregnancy test will be required before administration of study vaccine or placebo for all women of childbearing potential.)
• History of Guillain-Barre' Syndrome
• Any condition that, in the opinion of the investigator, would increase the health risk to the subject if he/she participates in the study or would interfere with the evaluation of the study objectives.