Implementation of pooled testing to increase access to routine viral load monitoring for people living with HIV on antiretroviral therapy

For the 30 million people living with HIV on antiretroviral therapy, routine viral load testing is recommended to monitor treatment effectiveness. However, only an estimated 77% of eligible people accessed viral load testing in 2022, due to barriers including the high costs of tests. Here we assessed implementation of pooled testing to increase viral load testing efficiency at a reference laboratory in Cameroon. Plasma specimens were tested in pools of three using the Abbott RealTime HIV-1 Viral Load assay. For pools with HIV-1 detected, each specimen was then tested and reported individually; for the negative pools, the pooled result was reported with no further testing. From July to December 2023, results for 12,396 specimens tested in pools were produced using 6,797 assays, or 0.55 assays per result, with 3.6% (449) reported as unsuppressed (> 1,000 copies/mL), enabling an additional 5,409 people (+ 80%) to have test results. When testing pools of three, the limit of detection per specimen increases from < 40 copies/mL to < 120 copies/mL, with only an estimated 0.01% of specimens with results of ≥ 1,001 copies/mL (unsuppressed) having results misclassified as suppressed. These results demonstrate that pooled testing can be an efficient and accurate approach to increase access to viral load monitoring.