Designing HIV testing algorithms based on 2015 WHO guidelines using data from six sites in sub-Saharan Africa

Cara S. Kosack, Leslie Shanks, Greet Beelaert, Tumwesigye Benson, Aboubacar Savane, Anne Ng'ang'a, Andre Bita, Jean-Paul B. N. Zahinda, Katrien Fransen, Anne-Laure Page

    Research output: Contribution to journalA1: Web of Science-article

    Abstract

    Our objective was to evaluate the performance of HIV testing algorithms based on WHO recommendations, using data from specimens collected at six HIV testing and counseling sites in sub-Saharan Africa (Conakry, Guinea; Kitgum and Arua, Uganda; Homa Bay, Kenya; Douala, Cameroon; Baraka, Democratic Republic of Congo). A total of 2,780 samples, including 1,306 HIV-positive samples, were included in the analysis. HIV testing algorithms were designed using Determine as a first test. Second and third rapid diagnostic tests (RDTs) were selected based on site-specific performance, adhering where possible to the WHO-recommended minimum requirements of >= 99% sensitivity and specificity. The threshold for specificity was reduced to 98% or 96% if necessary. We also simulated algorithms consisting of one RDT followed by a simple confirmatory assay. The positive predictive values (PPV) of the simulated algorithms ranged from 75.8% to 100% using strategies recommended for high-prevalence settings, 98.7% to 100% using strategies recommended for lowprevalence settings, and 98.1% to 100% using a rapid test followed by a simple confirmatory assay. Although we were able to design algorithms that met the recommended PPV of >= 99% in five of six sites using the applicable high-prevalence strategy, options were often very limited due to suboptimal performance of individual RDTs and to shared falsely reactive results. These results underscore the impact of the sequence of HIV tests and of shared false-reactivity data on algorithm performance. Where it is not possible to identify tests that meet WHO-recommended specifications, the low-prevalence strategy may be more suitable.

    Original languageEnglish
    JournalJournal of Clinical Microbiology
    Volume55
    Issue number10
    Pages (from-to)3006-3015
    Number of pages10
    ISSN0095-1137
    DOIs
    Publication statusPublished - 2017

    Keywords

    • WHO guidelines
    • diagnostic accuracy
    • diagnostic algorithms
    • human immunodeficiency virus
    • positive predictive value
    • rapid tests
    • CONFIRMATORY ASSAY
    • DIAGNOSTIC-TESTS
    • GEENIUS
    • UGANDA
    • RAKAI

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