Continued Safety and Immunogenicity Study of a Live Francisella Tularensis Vaccine

Inclusion Criteria: 1. At least 18 years old. 2. Females of childbearing potential must agree to have a urine or serum pregnancy test on vaccination day, immediately before vaccination (Exception: documented hysterectomy or \> 3 years of menopause). The results must be negative. Subjects must agree not to become pregnant for 3 months after receipt of the vaccine. 3. Subjects must be at risk for exposure to F. tularensis. 4. Subjects must have an up-to-date (within 1 year) medical history including concomitant medications, physical examination, and laboratory tests on their charts and be medically cleared for participation by an investigator. 5. Subject must be willing to return for all follow-up visits on days 1 and 2, between days 5-9, 12-16, 28-35, and 56-84 (if needed), all visits for serology, and the closeout interview 6 months (±14 days) after vaccination or revaccination. 6. Subject must agree to report any adverse event which may or may not be associated with administration of the test article for at least 28 days after vaccination. Exclusion Criteria: 1. Over the age of 65 Years. 2. Vaccinated against tularemia within the last 10 years or had a documented, confirmed tularemia infection. 3. Clinically significant abnormal lab results including evidence of hepatitis C, hepatitis B carrier state, or elevated liver function tests (two times the normal range or at the discretion of the PI). 4. Personal history of an immunodeficiency or current treatment with an oral or intravenous immunosuppressive medication. 5. Confirmed HIV\* infection. 6. A medical condition that, in the judgment of the Principal Investigator (PI), would impact subject safety. 7. Antibiotic therapy within 7 days before vaccination. 8. Pregnancy or lactation. Subjects must agree not to become pregnant for 3 months after receipt of the vaccine. 9. Any known allergies to any component of the vaccine: Modified casein partial hydrolysate medium Glucose cysteine hemin agar Sucrose gelatin agar stabilizer 10. Administration of another vaccine within 4 weeks of tularemia vaccination. 11. Any unresolved AE resulting from a previous immunization.