Study of Safety and Immunogenicity of HIV Vaccines in Healthy Volunteers

Background: \- Vaccines create resistance to disease. This study tests experimental human immunodeficiency virus (HIV) vaccines that use an adenovirus as a transporter. Transporters may help vaccines stimulate an immune response against HIV. This means the body works to fight infection. Researchers want to see if different ways of giving the vaccines cause different immune responses. They also want to see if the vaccines adenovirus is contagious. Adenoviruses cause cold symptoms or mild eye infections. Participants cannot get HIV from these vaccines. But they can get the adenovirus, so their entire household and intimate contacts must participate. Objective: \- To test the safety of experimental HIV vaccines. Eligibility: \- Healthy adults 18-49 years old. Design: * Participants will be screened with medical history, physical exam, and blood and urine tests. * Participants will receive the vaccine 3 times over 6 months. Each time, they will have a physical exam and blood and urine tests. Samples will be taken from their nose, rectum, and cervix. * Some participants will receive the vaccine by swallowing 11 capsules with water. Clinic staff will observe them for 1 hour. * Some participants will receive the vaccine swabbed in their throat. They will get dose 1 at the hospital and stay there for 1 week. They will have medical tests and nose swabs. Doses 2 and 3 will not require a hospital stay. * Participants will have 7 follow-up visits over 6 months, with a physical exam and blood tests. Samples will be taken from their nose, throat, and rectum. * Household and intimate contacts will have 4 clinic visits over 8 months, with a physical exam and blood tests.