During the study period the HIV prevalence for adults tested was 48%. All adult patients (age ≥18 years) who had undergone HIV testing during weekday business hours in the out-patient department and had a negative or discordant

rapid HIV test were eligible for this study. We excluded patients who were too ill to understand the counselling session or to provide informed consent, and patients known to be pregnant. Pregnant women were excluded because they are HIV tested in a physically different location at the hospital. Eligible patients who consented to participate in the study underwent venipuncture for HIV ATR inhibitor RNA, enzyme immunoassay (EIA) and Western blot (WB) on the Selleckchem LBH589 same day as the rapid HIV test and were asked to return for their results in 10 days. Study personnel contacted subjects found to be HIV-infected with the venipuncture specimen

who did not return in 10 days by telephone and advised them to return for test results. The project was approved by the McCord Hospital Ethics Committee (Durban, South Africa) and the Partners Human Subjects Committee (Protocol # 2006-P-001379/8) (Boston, MA, USA). During the 9-month study period, testing kits and procedures changed in the out-patient department as a result of changes in hospital policy and provincial Department of Health manufacturer tenders which were beyond the control of the study. The test kits included: Determine HIV 1/2 Test (Abbott Laboratories, Abbott Park, IL, USA), SmartCheck HIV 1&2 (World Diagnostic Inc., Miami Lakes, FL, USA), Sensa Tri-line HIV 1/2/0 (Hitech Healthcare Ltd, Beijing, China), and SD Bioline (Standard Diagnostics Inc., Suwon City, Korea). Initially, there was a period of serial testing (March–August 2007), followed by a period of parallel testing

(September–November 2007). During Histamine H2 receptor the serial testing period, a positive rapid screening test was confirmed by a second rapid test using a kit made by a different manufacturer. A single negative rapid HIV test was reported as negative. During the parallel testing period, two rapid tests were performed simultaneously for each patient. A rapid HIV test was reported to be negative if a patient had two parallel negative tests and positive if a patient had two parallel positive tests. Patients with one positive and one negative rapid test were considered ‘discordant’ but were included in the study because of a previously described association of discordant rapid HIV tests with acute HIV infection [15,20]. To ensure no evolution of serological response between rapid testing and WB, venipuncture specimens were collected in edetic acid (EDTA) tubes on the same day on which the rapid HIV test was performed. Plasma was removed from the whole blood specimens and stored daily.