HAALSI Baseline HIV Biomarker Data

For the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) baseline survey, HIV biomarkers were collected during the home survey through dried blood spots (DBS). DBS were tested for HIV, HIV viral load, and presence of antiretroviral drugs (emtricitabine and lamivudine, which are used in all standard first and second-line HIV regimens in South Africa). CD4 tests were performed on venous blood among the sub-sample of participants who visited the laboratory. * The HIV screening and confirmatory enzyme-linked immunosorbent assays used were the Vironostika HIV 1/2 Ag/Ab MicroELISA System (BioMérieux, Marcy-l’Étoile, France) and the Roche Cobas E411 Combi Ag, respectively. * The viral load platform was BioMérieux NucliSens with a lower limit of detection of 100 copies by DBS. * Testing for exposure to either emtricitabine (FTC) or lamivudine (3TC) was performed at the Pharmacokinetic Laboratory at the University of Cape Town in South Africa. A semiquantitative LC/MS/MS assay with a lower limit of detection of 0.02 mg/mL was validated for the determination of 3TC and FTC from DBS. The method consisted of a protein precipitation, followed by high-performance liquid chromatography with MS/MS detection using gradient elution.