This longitudinal, observational cohort study will be conducted at the Makerere University- Johns Hopkins University Research Collaboration, at the Mulago National Referral Hospital complex in Kampala Uganda. The study will consist of 2 groups. One group will consist of 25 healthy HIV uninfected adults and the other arm will consist of 35 HIV infected adults. Within the HIV infected arm there will be two groups, 25 HIV infected adults and 10 long term non-progressors. Vaccinees will receive a primary immunization at day 0, and blood samples will be obtained at days 0, 1, 3, 7, 14, 28 and 100 after immunization.