Challenges and pragmatic solutions for assessing the reliability of HIV-1 viral load monitoring in resource-constrained settings

Introduction: HIV-1 RNA detection is the most reliable method for monitoring treatment response among people living with HIV (PLHIV). Effective quality control measures that include internal quality control (IQC) are challenging in resource-constrained settings. Methods: We ascertained the utility of the assay low positive control (LPC) as an effective internal quality control (IQC) to monitor the reliability of the HIV-1 viral load assay. Variations in LPC values were measured for 390 different runs over ten years (2011-2021) and compared to in-house IQC data using Levey-Jennings control chart. Results: Overall, the Levey-Jennings analysis showed minimal variation (+/- 0.5 log) for both the LPC and IQC data. The mean LPC value for first 20 runs (20 days) was 2.91. The mean LPC value for the 390 runs comprising of 35 different lots, was 3.01 +/- 0.1 log. Conclusion: Our decadal data reveals that Abbott real-time HIV-1 assay (Abbott Molecular Inc., IL, USA) LPC exhibited no significant biological variation over 390 runs distributed over ten years. Hence, assay LPC can supplant the IQC for monitoring assay trends as a stable and commutable material in resource-constrained settings.