High level of HIV false positives using EIA-based algorithm in survey: Importance of confirmatory testing

• Published in: PloS one Vol. 15; no. 10; p. e0239782
• Main Authors: Augusto, Ângelo do Rosário, Iriemenam, Nnaemeka C., Kohatsu, Luciana, de Sousa, Leonardo, Maueia, Cremildo, Hara, Christine, Mula, Flora, Cuamba, Gercio, Chelene, Imelda, Langa, Zainabo, Lohman, Nathaniel, Faife, Flavio, Giles, Denise, Sabonete, Acacio Jose, Samo Gudo, Eduardo, Jani, Ilesh, Parekh, Bharat S.
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 22.10.2020; Public Library of Science (PLoS)
• Subjects: Accuracy; Acquired immune deficiency syndrome; AIDS; Algorithms; Antibodies; Biology and Life Sciences; Diagnosis; Disease control; Disease prevention; Enzyme immunoassay; Evaluation; Health surveillance; HIV; HIV tests; Households; Human immunodeficiency virus; Immunization; Immunoassay; Immunoenzyme techniques; Malaria; Medical diagnosis; Medical laboratories; Medical tests; Medicine and Health Sciences; Physical Sciences; Polls & surveys; Population; Research and Analysis Methods; Supervision; Vector-borne diseases; Mozambique; Atlanta Georgia; Georgia; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0239782

The Mozambique Indicators of Immunization, Malaria and HIV/AIDS (IMASIDA) survey was conducted in 2015 and used a two Enzyme Immunoassay (EIA) (Vironostika HIV-1/2 and Murex HIV-1/2) based algorithm to determine the HIV status of the consented participants. The Mozambique Ministry of Health, with support from the US Centers for Disease Control and Prevention (US CDC), added Bio-Rad Geenius[TM] HIV-1/2 Supplemental Assay to the IMASIDA HIV testing algorithm to confirm all specimens that were found to be reactive on one or both EIAs. In total 11690 specimens were collected to estimate the proportion of HIV positive samples. Results indicate that the proportion of HIV positive samples based on the concordant positive results of two EIA assays was 21.5% (2518/11690). The addition of the Geenius assay to the IMASIDA HIV testing algorithm demonstrated that 792 (31.5%) of 2518 specimens were false-positive and reduced the proportion of HIV positive samples to 14.7% (1722/11690), demonstrating the importance of including a highly specific HIV test to confirm HIV diagnosis. HIV surveys exclusively based on EIA testing algorithm may result in misleading high prevalence results. Our results demonstrate that more specific confirmatory testing should be added to the EIA-based algorithms to ensure accurate HIV diagnosis and correct HIV prevalence estimate in cross-sectional surveys.