The HIV epidemic in China has reached a phase of exponential growth. Among the infected are FBDs in rural communities, who became infected through contaminated blood collection equipment. In Fuyang, Anhui Province, China, unregulated commercial blood collection occurred from 1992 to 1995; during the last decade or so, some HIV infected FBDs have progressed to AIDS, while others are long-term nonprogressors, not requiring antiretroviral therapy (ART). Since the HIV infected participants in this study are predicted to have been infected by the same or related HIV strain because of their location and how they were infected, this is a unique population to study. It is hypothesized that host factors, such as host immunity and genetic background, are better predictors of disease progression than viral factors in this population. This study will enroll HIV-1 infected FBDs and age-matched HIV uninfected adults in Fuyang, Anhui Province, China.

There are two stages in this study. Stage I is a cross-sectional study and will last 3 months. Participants will be HIV-1 infected FBDs and age-matched HIV uninfected controls. There are two study visits in Stage I; there will be a 2-day screening/enrollment visit and a follow-up visit. On the first day of screening/enrollment, participants will be briefed about the study and will be asked to complete demographic and risk factor questionnaires; medical and medication history will be reviewed and a physical examination will also occur. All participants will receive HIV prevention education and risk reduction counseling; additionally, HIV uninfected participants will receive HIV pretest counseling. On the second day of screening, participants will return to the clinic for blood collection, and females will undergo a pregnancy test. All participants will return to the clinic to receive their laboratory results and post-test counseling at a follow-up visit occurring approximately 2 weeks after their screening/enrollment visit. Any participant with a CD4 count less than 200 cells/mm3 or meeting other China Comprehensive AIDS Response (CARES) treatment criteria will be referred for further evaluation and care. HIV infected FBD participants with a CD4 count of 200 cells/mm3 or more will be invited to enroll in Stage II.

Stage II is a longitudinal, prospective study and will last 19.5 months. Stage II will enroll eligible HIV infected participants from Stage I and if necessary, other eligible patients referred from China CARES. There will be at least five study visits; they will occur at a 2-day study screening/enrollment visit, a follow-up visit 2 weeks after screening/enrollment, and Months 6, 12, and 18. Screening/enrollment and follow-up visit procedures will be identical to those conducted in Stage I. Visits at Months 6, 12, and 18 will occur over 2-day periods. Medical and medication history will be reviewed and a physical examination will occur on the first day; participants will need to return to the clinic for blood collection on the second day. Participants will receive laboratory results and post-test counseling at the next scheduled study visit. Additional study visits may be required if a participant experiences any clinically significant condition during the study.