Dried blood spots versus plasma for the quantification of HIV-1 RNA using the manual (PCR-ELISA) amplicor monitor HIV-1 version 1.5 assay in Yaounde, Cameroon

Objectives: Considering the recent accrued need for viral load quantification in resource-limited settings, this study evaluated the use of dried blood spots (DBS) compared to plasma as a means of sample collection and storage for HIV-1 RNA quantification using a non-automated assay. Methods: Venous blood was collected from 60 consenting HIV-1-positive patients, plasma separated within 4 hours, and stored at -20°C. Venous blood, 50 μL, was blotted on 4 designated areas of Whatman filter paper and air-dried at room temperature for 2 hours. Results: There was a strong statistically significant correlation between HIV-1 RNA viral load using plasma and DBS (r =.955, P <.001). On average plasma viral loads were only slightly higher than DBS viral loads (mean difference: 0.06 log 10 copies/mL). Conclusion: Even when using an entirely manual HIV-quantification assay, DBS may provide a reliable, cost-effective method for sample collection and storage for HIV-1 RNA quantification in resource-limited settings. © 2009 The Author(s).