Evaluating the Safety and Immunogenicity of a H7N9 Vaccine for the Prevention of Influenza H7N9 Disease in Adults 50 to 70 Years Old

Inclusion Criteria: * Adult males and non-pregnant females between 50 years and 70 years of age inclusive. Children will not be recruited or enrolled in this study because they are not in the apparent risk group, and 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. Participants must be willing and able to remain within the Isolation Unit for the specified duration of confinement. * Willingness to participate in the study as evidenced by signing the informed consent document * Female participants of child-bearing 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 participants will be considered being of child-bearing potential except those who have undergone hysterectomy and those in whom menopause occurred at least 1 year prior to the study. * Agrees not to participate in another clinical trial with an investigational product for the entire duration of the study Exclusion Criteria: * Pregnancy as determined by a positive human choriogonadotropin (beta-HCG) test * Evidence of clinically significant neurologic, cardiac, pulmonary, hepatic, rheumatologic, autoimmune, or renal disease by history, physical examination, and/or laboratory studies including urine testing. Alanine aminotransferase (ALT) levels greater than 2 times the upper normal limit will be exclusionary at baseline, prior to vaccination. * Any current illness requiring daily medication other than the following: vitamins, birth control, anti-hypertensive medication, antihistamines, anti-depressant medication, cholesterol lowering medication, treatment for gastroesophageal reflux disease (GERD), and thyroid medication unless approved by the principal investigator. * Behavioral or cognitive impairment or psychiatric disease that in the opinion of the investigator affects the ability of the participant to understand and cooperate with the study protocol * Previous enrollment in an H7 or H9 influenza vaccine trial or in any study of an avian influenza vaccine * Seropositive to the H7N9 influenza A virus (serum HAI titer greater than 1:8) * Positive urine drug toxicology test indicating narcotic use/dependency * Have medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 12 months * Other condition that in the opinion of the investigator would jeopardize the safety or rights of a participant in the trial or would render the participant unable to comply with the protocol * History of anaphylaxis to any components of the H7N9 vaccines * Allergy to oseltamivir as determined by participant report * Current diagnosis of asthma or reactive airway disease (within the past 2 years) * History of Guillain-Barré Syndrome * Positive ELISA and confirmatory Western blot tests for human immunodeficiency virus-1 (HIV-1) * Positive ELISA and confirmatory test (e.g., recombinant immunoblot assay) for hepatitis C virus (HCV) * Positive hepatitis B virus surface antigen (HBsAg) by ELISA * Known immunodeficiency syndrome * Use of corticosteroids (excluding topical preparations) or immunosuppressive drugs within 30 days prior to vaccination * Receipt of a live vaccine within 4 weeks or a killed vaccine within 2 weeks prior to study vaccination * History of asplenia * Receipt of blood or blood-derived products (including immunoglobulin) within 6 months prior to study vaccination * Current smoker unwilling to stop smoking for the duration of the inpatient stay. A current smoker includes anyone stating they currently smoke or use any amount of a tobacco product, including electronic cigarettes. After admission to the unit, nicotine patches will be provided to current smokers who request them for the inpatient portion of the study. * Travel to the Southern Hemisphere within 14 days prior to study vaccination * Travel on a cruise ship within 14 days prior to study vaccination * Receipt of another investigational vaccine or drug within 30 days prior to study vaccination * Allergy to eggs, egg products, or formaldehyde