Inclusion Criteria:

Subjects must meet the following to be eligible for the study:

• adult males or females who provided informed consent for the study.
• adults 18 and 31 years (inclusive).
• good general health,
• female subjects must not be pregnant or lactating and be on appropriate contraception or be a female unable to bear children.
• subjects be available for participation during the entire study.

Exclusion Criteria:

Any of the following exclusion criteria are met, the subject is NOT eligible.

• military service prior to 1989 or after December 13th, 2002.
• history of previous smallpox vaccination
• known/suspected history of immunodeficiency, or with current radiation treatment or use of immunosuppressive or anti-neoplastic drugs.
• subjects with a household member or intimate contact with the same conditions listed above.
• known or suspected impairment of other immunologic function.
• malignancy, including squamous cell or basal cell skin cancer at vaccination site
• active autoimmune disease.
• subjects with known eye diseases or other conditions that require the use of corticosteroid eye drops.
• known/history of cardiac disease.
• subjects who have been diagnosed with 3 or more of the following risk factors for ischemic coronary disease: a) high blood pressure b) elevated blood cholesterol levels c) diabetes or high blood sugar d) first degree relative (for example, mother, father, brother, or sister) who had a heart condition before the age of 50 e) smoke cigarettes
• subjects with a history of palpitations or abnormalities of cardiac rhythm.
• subjects with odd ECG patterns
• subjects with a ten percent or greater risk of developing a myocardial infarction or coronary death within the next 10 years.
• positive or elevated creatinine kinase, CK-MB, or Troponin I laboratory test levels.
• abnormalities of clinical laboratory assessments.
• past history or current diagnosis of chronic renal disease, adverse reactions to drugs characterized by renal impairment, a serum creatinine > 1.5 mg/dL, or presence of 1+ protein in urinalysis at screening and a calculated creatinine clearance of not less than 80 mL/min.
• current diagnosis or past history of eczema.
• subjects with a household member or intimate contact with the same conditions listed above.
• presence of acute, chronic, or exfoliative skin conditions, open wounds, or burns.
• history of keloid formation.
• known allergies to MVA or to any known components (Neomycin, Gentamycin) of the vaccine.
• known allergy to eggs or egg products.
• known allergies to any component of the Dryvax® vaccine. Antibiotics in Dryvax® include neomycin, streptomycin, chlortetracycline, and polymixin B.
• known allergies to any known component of the Dryvax® diluent (i.e., glycerin and phenol).
• known allergies to any known component of VIG, (i.e., thimerosal or previous allergic reaction to immunoglobulins).
• known allergies to cidofovir or sulphur containing drugs, including probenecid, trimethoprim, and sulfonamide antibiotics.
• transfusion of blood or treatment with any blood product, including intramuscular or intravenous serum globulin within 6 months of the screening visit.
• positive serology result for HIV, hepatitis B surface antigen, or hepatitis C.
• current diagnosis or history within six months of the screening visit of drug or alcohol abuse disorders.
• significant acute or chronic psychiatric illness.
• female subjects with a positive serum pregnancy test result
• subjects with a household member or direct contact with someone who is pregnant or lactating.
• temperature or acute illness within 3 days prior to vaccination
• inoculation with an inactivated vaccine with 14 days of Day 0 or with a live attenuated vaccine within 30 days of Day 0.
• subjects who have participated in another investigational drug or vaccine trial within 30 days of Day 0.
• subjects who are planning on donating blood or organs within 30 days of vaccination.