Screening for HIV, Syphilis, and HSV-2

Participants provided 7 ml venous blood after pre-test counselling to test for HIV, syphilis, and HSV-2. Enzyme-linked immunosorbent assay (ELISA) (Vironostika HIV-1 Microelisa System; bioMerieux, Durham, NC) was performed to screen for HIV-1 antibody, and Western Blot (HIV Blot 2.2 WBTM, Genelabs Diagnostics, Singapore) was used to confirm positive cases. Syphilis was screened using a Rapid plasma reagin (RPR) test (Shanghai Kehua Bio-engineering Co., Ltd, China), and positive cases were confirmed by Treponema pallidum particle assay (TPPA) (Hainan Huamei, China). Only samples with positive results on both screening and confirmation tests were deemed HIV/syphilis positive. ELISA (HerpeSelect-2, Focus Technologies, USA) was used to determine the presence of an HSV-2 antibody infection. Confirmed HIV-positive specimens were tested for BED HIV-1 capture enzyme immunoassay (BED-CEIA, Calypte Biomedical Corporation, Rockville, MD, USA) to determine recently infected (HIV infected ≤168 days) or chronically infected (HIV infected >168 days) status [21 (link)].