Field Evaluation of Calypte’s AWARETM Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid Tests for Detecting Antibodies to HIV-1 and 2 in Plasma and Oral Fluid

Abstract

As programs to prevent and care for HIV-infected persons are scaled-up in Africa, there is the need for continuous evaluation of the performance of test kits that could best support these programs. The present study evaluated the sensitivity, specificity, ease of use, and cost of AWARE TM Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid HIV-1/2 test kits using real-time and archived samples of HIV-infected persons from Cameroon. Matched whole blood and OMT specimens were collected prospectively from HIV-positive and HIV-negative persons from different regions of Cameroon and tested using the AWARE TM BSP and OMT test kits, respectively. These results were compared to the gold standard that included a combination of Determine HIV-1/2 and Enzygnost HIV-1/2. The BSP Rapid test kit was further evaluated using well characterized panels of HIV-2 and HIV-1 group O samples. Cost and end-user analysis of the OMT test kit was done by comparing its actual cost, consumables, safety, bench time and manipulation with other test kits. Of the 732 matched samples, 412 (56.3%) and 320 (43.7%) were from females and males, respectively. Of these samples, 23 (3.1%) gave discordant results between Determine HIV-1/2 and Enzygnost HIV1/2 and were excluded from the analysis. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AWARETM BSP were 100%. The AWARETM OMT had 98.8% sensitivity, 98.9% specificity, 98.0% PPV and 99.4% NPV. The results of a well-characterized archived panel of HIV-2 (n=7) and HIV-1 group O (n=3) samples using the AWARETM BSP Rapid test kit gave 100% concordance. Total per patient cost of the AWARE OMT rapid test kit was US$4.72 compared to a mean cost of US $7.33 + 0.11 for the other test kits. Both the AWARETM BSP and OMT Rapid test kits demonstrated high sensitivities and specificities on all samples tested and were well adapted for use in resource-constrained settings with high HIV heterogeneity such as Cameroon. The AWARE TM HIV-1/2 OMT Rapid test kit appears to be the cheapest, safest and easiest to use compared with other available test kits.