Title: Recombinant Plague Vaccine rF1V in Healthy Volunteers

Primary Objective: To select a dosage and schedule of rF1V vaccine for further study based on the immune response to F1 and V antigens up to Day 210. Secondary Objectives: 1) To assess the safety of three injections of rF1V vaccine administered IM at two dosage levels. 2\) To assess the onset and duration of the humoral immune response to F1 and V antigens. 3\) To assess the humoral immune response to rF1V antigen. 4) To collect and store blood samples for future plague related research. Exploratory Objectives: To assess additional humoral immune responses to rF1V vaccine antigens.