Safety and Immunogenicity of Priming With Live Attenuated A/H7N9 Influenza Virus Vaccine Followed By Inactivated A/H7N9 Influenza Virus Vaccine With AS03 Adjuvant

Inclusion Criteria: * Adult males and non-pregnant, non-breastfeeding females between 20 years and 49 years of age, inclusive. Children will not be recruited or enrolled in this study because they are not in the apparent risk group, for safety considerations, and because of the need for isolation. * Are in good health, as determined by medical history and targeted physical examination to ensure any existing medical diagnoses or conditions (except those exclusionary) are stable. More information on this criterion can be found in the protocol. * Agree to storage of blood specimens for future research. * Available for the duration of the trial. Subjects must be willing and able to remain within the Isolation Unit for the specified duration of confinement. * Provide written informed consent prior to initiation of any study procedures, including future use of specimens. * Female subjects of childbearing potential must agree to use effective birth control methods for the duration of the study (for example, pharmacologic contraceptives including oral, parenteral, and transcutaneous delivery; condoms with spermicide; diaphragm with spermicide; intrauterine device; abstinence from heterosexual intercourse, surgical sterilization). All female subjects will be considered being of childbearing potential except those who have undergone hysterectomy or tubal ligation and those in whom menopause occurred at least 1 year prior to the study. * Agrees not to participate in another clinical tr…