Strategies for Enhancing Mucosal Immunity to Influenza Vaccine

The purpose of this study is to determine the safety and effectiveness of the influenza vaccine when administered nasally and intra-muscular (a "shot" of medicine given into a muscle). The investigators will measure the systemic (through out the body) and mucosal immune responses (how your body recognizes and defends itself against bacteria) to nasally administered influenza vaccine, and determine if nasal immunization results in immunity (your body's ability to avoid infections) within multiple mucosal compartments (ocular (eye), oral and reproductive), in comparison with intramuscular administration and placebo (inactive substance given in the same form as the active drug).