Decentralization of viral load testing to improve HIV care and treatment cascade in rural Tanzania: observational study from the Kilombero and Ulanga Antiretroviral Cohort

Abstract

Introduction Monitoring HIV viral load (HVL) in people living with HIV (PLHIV) on antiretroviral therapy (ART) is recommended by the World Health Organization. Implementation of HVL testing programs have been affected by logistic and organizational challenges. Here we describe the HVL monitoring cascade in a rural setting in Tanzania and compare turnaround times (TAT) between an on-site and a referral laboratory. Methods In a nested study of the prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) we included PLHIV aged ≥ 15 years, on ART for ≥ 6 months after implementation of routine HVL monitoring in 2017. We assessed proportions of PLHIV with a blood sample taken for HVL, whose results came back, and who were virally suppressed (HVL < 1000 copies/mL) or unsuppressed (HVL ≥ 1000 copies/mL). We described the proportion of PLHIV with unsuppressed HVL and adequate measures taken as per national guidelines and outcomes among those with low-level viremia (LLV; 100–999 copies/mL). We compare TAT between on-site and referral laboratories by Wilcoxon rank sum tests. Results From 2017 to 2020, among 4,454 PLHIV, 4,238 (95%) had a blood sample taken and 4,177 (99%) of those had a result. Of those, 3,683 (88%) were virally suppressed. In the 494 (12%) unsuppressed PLHIV, 425 (86%) had a follow-up HVL (102 (24%) within 4 months and 158 (37%) had virologic failure. Of these, 103 (65%) were already on second-line ART and 32/55 (58%) switched from first- to second-line ART after a median of 7.7 months (IQR 4.7–12.7). In the 371 (9%) PLHIV with LLV, 327 (88%) had a follow-up HVL. Of these, 267 (82%) resuppressed to < 100 copies/ml, 41 (13%) had persistent LLV and 19 (6%) had unsuppressed HVL. The median TAT for return of HVL results was 21 days (IQR 13–39) at the on-site versus 59 days (IQR 27–99) at the referral laboratory (p < 0.001) with PLHIV receiving the HVL results after a median of 91 days (IQR 36–94; similar for both laboratories). Conclusion Robust HVL monitoring is achievable in remote resource-limited settings. More focus is needed on care models for PLHIV with high viral loads to timely address results from routine HVL monitoring.

Evaluation of HIV Viral Load Surveillance System, National Perspective in Tanzania

“…The high percentage of coverage could be attributed to country strategies of free HIV care and treatment services including consultation, testing, medications, and follow-up. We found a system sensitivity of 84.4%; this could be attributed to six multi-month dispensing (6MMD) in the country that delayed the eligible clients from taking HVL samples for testing, which started in 2022 (5). Regardless the challenge noted, it has been reported that giving stable customers multi-month dispensing (MMD) of ARV improves health outcomes in terms of immunosuppression, viral suppression, retention, mortality, and adherence (13–15).…”

“…HVL testing and monitoring has complex technical and logistic requirements requiring continuous expert guidance and a reliable quality management system. Some countries, including Tanzania, have adopted a hub-and-spoke model coupled with clustering clinics and efficient specimen collection, transportation and referral systems (5).…”

“…HVL testing for monitoring HIV care and treatment among people living with HIV was started in Tanzania in 2017, with the growth of the hub-and-spokes approach for sample processing and transportation and the scaling up of testing facilities. Tanzania has seen a notable rise in HVL testing since 2017 (5). The nation has concentrated on tracking the quantity of HIV clients who are tested and following up with them along the HVL cascade, especially in cases when the client has a high viral load.…”

Virological Non-Suppression among Newly Diagnosed HIV-Positive Individuals on Dolutegravir-Based Antiretroviral Treatment in Eastern Ethiopia: Follow-Up Study

“…As a result, taking the initiative for baseline VL testing for HIV-positive clients starting ART may be required to properly monitor ART adherence from the start and optimize the benefits of HIV care and treatment programs. Furthermore, cost-effective, affordable, rapid, and decentralized VL testing might increase the uptake of baseline VL and viral suppression in general [ 26 , 50 , 51 ]. Moreover, considering pretreatment HIV drug resistance genotypic testing at baseline could be helpful in identifying patients at a higher risk of virological failure and contribute to the long-term success of viral suppression [ 52 ].…”

“…It is available as a once-daily dosing for HIV patients, has a high genetic barrier to resistance, and is safer than non-DTG-based cART [ 25 ]. However, there were limited data on baseline VL testing before the initiation of ART in LMICs, including Ethiopia, because of its rigorous laboratory work, long turnaround times, and lack of adequate infrastructure and supplies [ 26 ]. Furthermore, since the rollout of DTG-based regimens as first-line ART in Ethiopia, no study has linked baseline factors, including the VL test, with virological non-suppression after six months of follow-up on ART.…”