Murex hiv 1.2 o hiv enzyme immunoassay

At the central laboratory, the same validated HIV testing algorithm that was used in KAIS 2007 was applied to KAIS 2012 blood samples. All specimens were initially screened with Vironostika HIV-1/2 UNIF II Plus O Enzyme Linked Immunoassay (bioMérieux, Marcy l’Etoile, France). Specimens that were reactive were then tested with the Murex HIV.1.2.O HIV Enzyme Immunoassay (DiaSorin, SpA, Saluggia, Italy) to confirm reactivity. Specimens with discrepant results were retested using the same algorithm. Twice discrepant results were resolved using polymerase chain reaction (Cobas Amplicor HIV-1 Monitor Test, version 1.5, Roche Molecular Diagnostics, Pleasanton, CA). HIV-positive dried blood spot specimens were tested for HIV RNA concentration using the Abbott M2000 Real-Time HIV-1 Assay (Abbott Laboratories, Abbott Park, IL) and recent HIV infection using the Limiting Antigen Avidity Enzyme Immunoassay (LAg-Avidity EIA) (Maxim Biomedical, Inc., Rockville, MD). Specimens with a normalized optical density value of 1.5 or lower on the LAg-Avidity EIA and (1) not virally suppressed (defined as HIV RNA concentration <1000 copies/mL) or (2) did not report use of antiretroviral therapy (ART) for their HIV infection were classified as indicative of recent infection. The estimated mean duration of recent infection for the assay was 130 days (95% confidence interval [CI] 118 to 142).

Biologic testing was performed at the National HIV Reference Laboratory. HIV testing was done using Kenya’s validated testing algorithm, which included screening with Vironostika HIV-1/2 UNIF II Plus O Enzyme Immunoassay (bioMérieux, Marcy d’Etoile, France). Positive samples were confirmed with the Murex HIV.1.2.O HIV Enzyme Immunoassay (DiaSorin, SpA, Saluggia, Italy). Discordant results were retested with the 2 assays. Twice discordant results, if they occurred, were tested using a polymerase chain reaction assay (Cobas Amplicor HIV-1 Monitor Test, version 1.5; Roche Molecular Diagnostics, Pleasanton, CA). For quality control, all positive specimens and 5% of negative specimens were retested using the same testing algorithm at the Kenya Medical Research Institute laboratory. For persons with positive HIV tests, measurements of CD4 cell counts (BD FACSCalibur Flow Cytometer; Becton Dickinson Biosciences, San Jose, CA) were performed centrally as well as measurement of HIV viral load (Abbott M2000 Real-Time HIV-1 Assay; Abbott Laboratories, Abbott Park, IL).

We asked parents or guardians of eligible children for their verbal consent to collect a blood sample for biologic testing and extended storage for future unspecified testing at the National HIV Reference Laboratory (NHRL) in Nairobi. At NHRL dried blood spot specimens were tested for HIV antibody using the Vironostika HIV-1/2 UNIF II plus O Enzyme Immunoassay (bioMérieux SA, Marcy l’Etoile, France) and confirmed using the Murex HIV.1.2.O HIV Enzyme Immunoassay (DiaSorin SpA, Saluggia, Italy). Repeat testing was done for discordant results, and, if results remained discordant, a final determination was made using polymerase chain reaction for HIV antigen (Cobas Amplicor HIV-1 Monitor Test, version 1.5; Roche Molecular Diagnostics, Pleasanton, CA). We tested all confirmed HIV-positive blood specimens for HIV RNA concentration (Abbott M2000 Real-Time HIV-1 Assay; Abbott Laboratories, Abbott Park, IL). Test results from the NHRL were not returned to study participants. Home-based HIV testing and counseling, using rapid tests according to the national HIV testing algorithm, was offered to all persons participating in the survey, including parents and guardians of participating children.