Immunogenicity Study of S-OIV H1N1 Influenza Vaccine

The primary immunogenicity objective is to assess the antibody response and T-cell response of split-virion inactivated A (H1N1) vaccine. Participants will include up to 20 healthy persons of age 20 and older who have no history of novel influenza H1N1 2009 infection in latest 3 months or novel influenza H1N1 2009 vaccination. This is a randomized study in healthy males and non-pregnant females, aged 20 years and older. All subjects will be stratified into 1 dose group (15mcg per dose), and will receive intramuscular influenza H1N1 vaccine. The H1N1 vaccine will be administered at Day 0 and Day 21. On Day 0, Day 10, Day 21, Day 28, Day 35 and Day 42 after first vaccination (Day 0), the immunogenicity testing will be manipulated. The antibody response of immunogenicity testing will be hemagglutination inhibiting (HAI) on serum. The T-cell response will be interferon-gamma ELISPOT assay and Tetramer staining using PBMCs.