Patient Inclusion Criteria

Able to understand and communicate in written and spoken English. - Judged to be able to provide informed consent and has signed informed consent form prior to study participation. - Male or female between 18 and 40 years of age. - Females of childbearing potential agree to practice adequate contraception for the entire study period. - Good general health as confirmed by medical history, history-directed physical examination, and laboratory assessments within normal ranges established by Baylor College of Medicine. - Availability for follow-up for six months after the first vaccination. - Willing and able to comply with protocol requirements.

Patient Exclusion Criteria

Clinically significant medical disorder found by medical history or physical exam. - History of anaphylaxis or other significant adverse event following immunization. - History of or planned exposure to small mammalian animals that are from Asia, or were previously housed with Asian counterparts. - Pregnant or lactating female. - Acute illness (cough, congestion, malaise, diarrhea, feverishness and/or oral temperature > 99.5 degrees Fahrenheit, etc.) within a week of planned vaccination. - Use of an immunosuppressive or immunomodulatory drug such as greater than 5 mg/day of prednisone orally, or greater than 800 mcg/day of inhaled beclomethasone for 2 or more consecutive weeks within 3 months prior to the first vaccination. - History of or current substance abuse, including alcohol (e.g., greater than or equal to 4 six-packs of beer or equivalent per week regularly). - History of receiving blood or blood products in the previous three months, or anticipated over the six month study period. - Vaccination with a live vaccine within 30 days of study vaccination, or a non-replicating, inactivated or subunit vaccine within 14 days of study vaccination, or planned during the study. - Positive serology for human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B surface antigen (HbsAg). - Positive serology for severe acute respiratory disease (SARS) S protein if testing is done. - Use of any investigational or unregistered drug or vaccine within 30 days before the first study vaccination, or planned use during the study. - Autoimmune disease (e.g., lupus, rheumatoid arthritis), malignancy or tumor. - Bleeding disorder by history, or thrombocytopenia. - Diagnosis of schizophrenia, bipolar disease or other major psychiatric disorder. - Have been hospitalized for psychiatric illness, history of suicide attempt, or confinement for danger to self or others. - Are receiving psychiatric drugs (aripiprazole, clozapine, ziprasidone, haloperidol, loxapine, thioridazine, molindone, thiothixene, pimozide, fluphenazine, risperidone, mesoridazine, quetiapine, trifluoperazine, chlorprothixene, chlorpromazine, perphenazine, trifluopromazine, olanzapine, carbamazepine, divalproex sodium, lithium carbonate or lithium citrate). Subjects who are receiving a single antidepressant drug and are stable for at least 3 months prior to enrollment, without de-compensating symptoms will be allowed to be enrolled in the study. - Plans to enroll in another study before study completion (six months).