Characterizing the Human Airway Immune Response to FluMist Vaccination

Study Design/Methodology: Prospective randomized controlled trial; Study Duration: 2 years; Number of Subjects: 30; Subject Participation Duration: 4 months; Description of Interventions: Eligible healthy participants who have not received a seasonal influenza vaccine within the past 9 months will complete written informed consent. Enrolled participants will be randomized to receive either an FDA-approved intramuscular seasonal egg-based inactivated influenza vaccine (IIV) (N=15) or the FDA-approved seasonal FluMist intranasal live attenuated influenza vaccine (N=15) on study day 0. Blood samples and nasopharyngeal swabs will be collected at the time of study enrollment (up to 45 days prior to vaccination) and on days 3±1, 7±2, 14±3, 28±5, and 90±14 post-vaccination. Sixteen participants (N=8 in each vaccine group) will be enrolled for optional research bronchoscopy procedures. Research bronchoscopies will include bronchoalveolar lavage (BAL) and endobronchial biopsy (EBBx) sample collection. Research bronchoscopies will be performed prior to vaccination and on study days 14±3 and 90±14. Screening safety laboratory studies and screening chest x-ray imaging will be performed on subjects undergoing research bronchoscopies.