Evaluating the Safety and Immunogenicity of a Live Attenuated Virus Vaccine to Prevent Influenza H3N2v Disease

Inclusion Criteria: * Males and non-pregnant females between 6 and 26 years of age inclusive. * For children, presence of an adult caregiver who is in good health and able to understand and carry out the requirements * General good health, without significant medical illness, physical examination findings, or significant laboratory abnormalities as determined by the investigator. * Agree to storage of blood specimens for future research. * Available for the duration of the trial. * Willingness to participate in the study as evidenced by signing the informed consent document. Verbal assent will be obtained from minors 6 to 12 years of age and signed assent will be obtained from minors 13 and older. * Female subjects of childbearing potential must agree to use effective birth control methods for the duration of the study (e.g., pharmacologic contraceptives including oral, parenteral, and transcutaneous delivery; condoms with spermicide; diaphragm with spermicide; intrauterine device; abstinence from heterosexual intercourse, surgical sterilization). Exclusion Criteria: * Anticipated direct routine \[e.g. weekly or more frequent\] contact with individuals younger than the designated age groups being studied as a result of household contact, occupation, or participation in day care with such individuals. * Pregnancy as determined by a positive urine or serum human choriogonadotropin (β-HCG) test. * Currently breast-feeding. * Evidence of clinically significant neurologic, card…