Randomization and Post-Randomization Visits After undergoing the nasal swabs and nasopharyngeal washes, and nasal epithelial brushing, healthy volunteers will be randomly assigned to receive either saline nasal spray (placebo) or FluMist® nasal influenza vaccine (live attenuated influenza vaccine, or LAIV). They will return 1-2 weeks and 4-6 weeks later to repeat the nasal swabs and nasopharyngeal washes, and nasal epithelial brushings done at the Enrollment Visit.
Samples will be processed to isolate 16s bacterial RNA and host RNA. 16s rRNA will be analyzed by 16S sequencing for to determine the composition of the bacterial microbiome pre and post LAIV or saline (placebo) administration. Host immune responses will be assessed based upon microarray analysis of host RNA pre and post LAIV or saline administration.
