A study published in Dec 2015 by Priyadarshini A. Padaki et al. from CMC Vellore, India, evaluated Cavidi’s viral load ExaVir Load for use in resource limited settings and compared it with two PCR assays. Compared with the routine molecular viral load assays, Cavidi version 3.0 is inexpensive, user-friendly, the expenditure on infrastructure is minimal, and it can be used for monitoring of both HIV types.
The RT-based viral load assay performed well compared to the PCR assays from Abbott and Qiagen when measuring HIV-1 samples, did not show positives for HIV when measuring samples positive for HBV and HCV, and could also measure the viral load for HIV-2 samples. The authors of the study summarized some of their findings as follows:
“The advantage of the Cavidi version 3.0 assay over molecular techniques is that it could be performed in any secondary level laboratory with the routinely available equipment such as ELISA washer, ELISA plate reader, vortex machine,and an incubator.Compared with viral load estimations by molecular assays it is inexpensive and simple to perform. The expenditure on infrastructure is minimal for Cavidi version 3.0. Also it has good sensitivity and correlation with the molecular assays, as also demonstrated in the present study. The cost per test is also much lower when compared with the molecular assays (US $20 vs US $67). Another major advantage of the assay is that a single assay can be used for both HIV-1 and HIV-2 samples.
These characteristics with comparable performance with molecular assays make the Cavidi version 3.0 RT assay suitable for use in settings with limited infrastructure for monitoring the viral load in individuals with HIV as an alternative to PCR. Based on the sensitivity (lower detection of 1000 copies/ml) and specificity of this assay, resource-poor countries can establish this kind of viral load monitoring assay in all secondary level reference laboratories with good quality control measures, including EQAS from apex and national reference laboratories.”
This study was published in Infectious Diseases 11 December 2015. The study was carried out by Priyadarshini A. Padaki, Jaiprasath Sachithanandham, Rita Isaac, Veena V. Ramalingam, Ooriapadickal C. Abraham, Susanne A. Pulimood & Rajesh Kannangai