Dataset Information

Prevalence and incidence estimation of HSV-2 by two IgG ELISA methods among South African women at high risk of HIV.

ABSTRACT:

Introduction

Previous comparison studies of the Kalon and HerpeSelect 2 ELISA IgG assays on sub-Saharan samples have found differences in the sensitivity and specificity of these assays. Using longitudinal samples from an HIV prevention study, we compared both assays and determined the HSV-2 prevalence and incidence in a South African young female population at elevated risk of acquiring HIV.

Methods

Samples at baseline were tested in both assays using the manufacturers' guidelines (cut-off > 1.10). When non-reactive in one assay, the final visit samples were tested to determine the incidence rate. Using correlation and regression analyses, the intra- and inter-assay variabilities were assessed.

Results

The prevalence rate was 41.1% and 44.9% for Kalon and HerpeSelect using the manufacturer guidelines, respectively. Agreement between the two tests were high (kappa = 0.92). The original optical density values of both assays were highly correlated (R = 0.94), but the calibrator and correspondingly cut-off index values differed between the assays. Lowering the index value cut-off for the Kalon assay by 40% (to 0.66) resulted in a HSV-2 prevalence of 43.2%, and increased agreement between the assays (to kappa = 0.96). The incidence rate was 16.3/100 Person Years using the lower cut-off for the Kalon assay.

Discussion

In this longitudinal study, we showed that the performance of the two assays was very similar. After lowering the cut-off for the Kalon assay to 0.66 early infections were detected without impairing its specificity. The prevalence and incidence rates are in line with previously described rates for sub-Saharan African cohorts.

SUBMITTER: De Baetselier I

PROVIDER: S-EPMC4370866 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Prevalence and incidence estimation of HSV-2 by two IgG ELISA methods among South African women at high risk of HIV.

De Baetselier Irith I Menten Joris J Cuylaerts Vicky V Ahmed Khatija K Deese Jennifer J Van Damme Lut L Crucitti Tania T

PloS one 20150323 3

<h4>Introduction</h4>Previous comparison studies of the Kalon and HerpeSelect 2 ELISA IgG assays on sub-Saharan samples have found differences in the sensitivity and specificity of these assays. Using longitudinal samples from an HIV prevention study, we compared both assays and determined the HSV-2 prevalence and incidence in a South African young female population at elevated risk of acquiring HIV.<h4>Methods</h4>Samples at baseline were tested in both assays using the manufacturers' guideline ...[more]

PMID: 25799522

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Dataset Information

Prevalence and incidence estimation of HSV-2 by two IgG ELISA methods among South African women at high risk of HIV.

Introduction

Methods

Results

Discussion

Publications

Prevalence and incidence estimation of HSV-2 by two IgG ELISA methods among South African women at high risk of HIV.

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