Safety and Immunogenicity of Q Fever Vaccine

Inclusion Criteria: * At least 18 years old. * Females of childbearing potential must agree to have a urine pregnancy test on the same day before receipt of skin test AND vaccine. (Exception: documented hysterectomy or ≥ 3 years of menopause.) The results must be negative. Females must agree to not become pregnant for 3 months after receipt of the skin test or vaccination. * Considered at risk for exposure to C burnetii and who have submitted a Request for Investigational New Drug (IND) Vaccines for the Q Fever vaccine. * Sign and date the approved informed consent document and Health Insurance Portability and Accountability Act (HIPAA) Authorization. * Have on their charts: * Up-to-date medical history (including concomitant medications) * Physical examination and laboratory tests within 1 year * Previous chest x-ray and electrocardiogram * Be medically cleared for participation by an investigator. Examinations or tests may be repeated at the discretion of the enrolling physician. * Willing to return for all follow-up visits. * Agree to report any adverse events (AEs) that may or may not be associated with administration of the test article for at least 28 days after vaccination and agree to report all serious adverse events (for example, resulting in hospitalization) for the duration of the subject's participation in the study (6 months). * Agree to defer blood, bone marrow, and organ donation for 1 year after receipt of skin test antigen and/or vaccine. Exclusion Criteria: * Prior history of Q fever disease or vaccination. * 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 principal investigator). * Personal history of an immunodeficiency or current treatment with an oral or intravenous immunosuppressive medication. * Confirmed HIV infection. * Heart valve disease: prosthetic heart valve or clinically significant heart murmur. (If a murmur is detected on examination, an echocardiogram may be obtained or subject may be referred to a cardiologist to determine clinical significance.) * Aneurysm/vascular graft. * Joint prosthesis. * History of chronic fatigue syndrome (or positive by chronic fatigue syndrome (CFS) Questionnaire criteria). * Positive pregnancy test or breast-feeding female. * Any known allergies to components of the vaccine: * Formalin * Eggs or chicken products * Administration of another vaccine or investigational product within 28 days of skin test and subsequent Q fever vaccination. * Any unresolved AE resulting from a previous immunization. * Transplant recipients, subjects with cancer, and those with chronic kidney disease. * A medical condition that, in the judgment of the principal investigator, would impact subject safety.