Limited access to HIV treatment is a major problem in many parts of the world. If a well tolerated anti-HIV regimen with convenient once-daily dosing is effective in reducing viral load in people with recent or early HIV infection, this regimen could be used globally for controlling HIV. This study will determine the effectiveness of a three-month antiretroviral regimen in reducing viral load in HIV infected adults who were recently infected or have recently seroconverted. This study will recruit participants from Alabama and Tennessee in the United States and in Lusaka, Zambia.

Participants in this study must also be enrolled in the AIEDRP CORE01 study. Participants in this study will be divided into Early and Acute groups. Participants in the Early group will be people who have recently seroconverted; participants in the Acute group will be people with primary HIV infection. All participants will choose to receive the once-daily dosing regimen of emtricitabine, nevirapine, and tenofovir disoproxil fumarate. Didanosine, efavirenz, and stavudine may be substituted for other drugs in the regimen at the investigator's discretion. Participants will take the three-drug regimen for 90 days. If a participant's CD4 count is higher than 350 cells/mm3 at Day 90, the participant will stop therapy. If a participant's CD4 count is 350 cells/mm3 or lower at Day 90, or if the participant's CD4 count drops to 350 cells/mm3 or lower while therapy is stopped, the participant will receive an additional 30 days of therapy. This therapy strategy may be repeated as necessary up to Day 180. All participants taking the three-drug regimen will be followed, regardless of whether or not they have taken the regimen beyond Day 90.

In addition to AIEDRP CORE01's study visits, 7 additional study visits will occur at pretreatment, on Day 3, and at Weeks 1, 3, 8, 16, and 20. Blood collection will occur at all study visits. Data from study participants will be compared with data from a historical cohort of previously identified HIV infected adults with acute or early infection who did not receive treatment but were followed prospectively.