Inclusion Criteria

Patients must be:

• Normal, healthy, HIV-negative adults who fully comprehend the purpose and details of the study.
• Available for 1 year of follow-up.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

• History of positive PPD (tuberculin test).
• Positive syphilis serology (e.g., VDRL).
• Positive for circulating hepatitis B antigen.

Patients with the following are excluded:

• They or their sexual partners have identifiable high-risk behavior for HIV infection.
• History of immunodeficiency or chronic illness.
• Evidence of depression or under treatment for psychiatric problems during the past year.

Prior Medication:

Excluded:

• Immunosuppressive medications.

Prior Treatment:

Excluded:

• Blood transfusions or cryoprecipitates within the past 6 months.

Risk Behavior: Excluded:

• High-risk behavior for HIV infection.
• History of intravenous drug use.
• More than one sexual partner in the last 6 months.