COMPARISON OF THE BED-IgG CAPTURED EIA HIV-1 INCIDENCE ASSAY WITH THE WHOCRITERIA FOR IDENTIFYING RECENTLY HIV INFECTED INDIVIDUALS FOR ENROLLMENT IN THE HIVDR-TS

Abstract

Background: With the advent of antiretroviral therapy (ART) in several developing countries, WHO has proposed that countries should monitor HIV drug resistance (HIVDR) based on a population-based threshold survey. The guideline uses agecriteria to identify newly infected individuals. The accuracy of such guideline has not been validated, however.
Objective: To compare the WHO criteria for identifying recently infected individuals with a biological marker HIV-1 BED incidence assay.
Methods: Individuals were enrolled from the VCT center, Addis Ababa, Ethiopia. Initial HIV screening was done based on
current national Rapid HIV screening algorithm. Based on the WHO criteria, HIV-positive was classified as recently infected if
less than 25years of age. Moreover the HIV-positive specimens were retested by two conventional EIA tests and discrepant
results were confirmed by Western blot test. Then using the bio-marker HIV-1 BED incidence assay to classify the recent infection for comparison with the WHO-criteria.
Results: A total of 4492 individuals underwent VCT and screened for HIV. Of these 360 (8.0 %) were found to be HIV-positive;
64 (1.4%) were identified as recently infected based on the WHO criteria. Forty-two (0.93%) were identified as recently infected by the HIV-1 BED incidence assay, giving an estimated incidence of 2.36 % per year [95% CI, 1.7-3.1]. However, the
strength of agreement between the WHO criteria and BED assay is considered to be poor to fair K=0.29 (95% CI, 0.11 – 0.47).
Conclusion: The concordance between WHO criteria and BED assay is low. This shows that whether the WHO criteria over
estimate or the BED assay under estimates recent infection (or vice versa) is difficult to identify. In the absence of current gold
-standard to decide which of the above criteria is more accurate, the need for identifying recent HIV infection for the purpose
of population based studies is urgent