High level of HIV false positives using EIA-based algorithm in survey: Importance of confirmatory testing
Ângelo do Rosário Augusto1, Nnaemeka C Iriemenam2, Luciana Kohatsu2,3
1Instituto Nacional de Saúde (INS), EN1, Distrito de Marracuene, Maputo, Mozambique.
Plos One
|October 22, 2020
Summary
The Mozambique Indicators of Immunization, Malaria and HIV/AIDS (IMASIDA) survey found high HIV prevalence using Enzyme Immunoassay (EIA) tests alone. Adding a confirmatory Geenius assay significantly reduced false positives, improving accuracy.
Area of Science:
- Epidemiology
- Infectious Diseases
- Public Health
Background:
- The Mozambique Indicators of Immunization, Malaria and HIV/AIDS (IMASIDA) survey aimed to estimate HIV prevalence.
- Initial HIV testing relied on a two-Enzyme Immunoassay (EIA) algorithm.
Purpose of the Study:
- To evaluate the impact of adding a supplemental HIV test to the IMASIDA testing algorithm.
- To assess the accuracy of HIV prevalence estimates derived from EIA-only testing.
Main Methods:
- The study utilized data from the 2015 IMASIDA survey involving 11,690 participants.
- Two EIAs were used, followed by the Bio-Rad Geenius™ HIV-1/2 Supplemental Assay for confirmation.
- HIV status was determined based on EIA results and confirmatory testing.
Main Results:
- Initial EIA testing indicated an HIV prevalence of 21.5%.
- The Geenius assay identified 31.5% of initially reactive samples as false positives.
- Implementing confirmatory testing reduced the estimated HIV prevalence to 14.7%.
Conclusions:
- Exclusive reliance on EIA testing can lead to inflated HIV prevalence estimates.
- Incorporating specific confirmatory assays like Geenius is crucial for accurate HIV diagnosis in surveys.
- Accurate HIV prevalence data is essential for effective public health interventions and resource allocation.
