Dataset Information

Viral load monitoring of antiretroviral therapy, cohort viral load and HIV transmission in Southern Africa: a mathematical modelling analysis.

ABSTRACT:

Objectives

In low-income settings, treatment failure is often identified using CD4 cell count monitoring. Consequently, patients remain on a failing regimen, resulting in a higher risk of transmission. We investigated the benefit of routine viral load monitoring for reducing HIV transmission.

Design

Mathematical model.

Methods

We developed a stochastic mathematical model representing the course of individual viral load, immunological response and survival in a cohort of 1000 HIV-infected patients receiving antiretroviral therapy (ART) in southern Africa. We calculated cohort viral load (CVL; sum of individual viral loads) and used a mathematical relationship between individual viral load values and transmission probability to estimate the number of new HIV infections. Our model was parameterized with data from the International epidemiologic Databases to Evaluate AIDS Southern African collaboration. Sensitivity analyses were performed to assess the validity of the results in a universal 'test and treat' scenario, wherein patients start ART earlier after HIV infection.

Results

If CD4 cell count alone was regularly monitored, the CVL was 2.6 × 10 copies/ml and the treated patients transmitted on average 6.3 infections each year. With routine viral load monitoring, both CVL and transmissions were reduced by 31% to 1.7 × 10 copies/ml and 4.3 transmissions, respectively. The relative reduction of 31% between monitoring strategies remained similar for different scenarios.

Conclusion

Although routine viral load monitoring enhances the preventive effect of ART, the provision of ART to everyone in need should remain the highest priority.

SUBMITTER: Estill J

PROVIDER: S-EPMC3750130 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Publications

Viral load monitoring of antiretroviral therapy, cohort viral load and HIV transmission in Southern Africa: a mathematical modelling analysis.

Estill Janne J Aubrière Cindy C Egger Matthias M Johnson Leigh L Wood Robin R Garone Daniela D Gsponer Thomas T Wandeler Gilles G Boulle Andrew A Davies Mary-Ann MA Hallett Timothy B TB Keiser Olivia O

AIDS (London, England) 20120701 11

<h4>Objectives</h4>In low-income settings, treatment failure is often identified using CD4 cell count monitoring. Consequently, patients remain on a failing regimen, resulting in a higher risk of transmission. We investigated the benefit of routine viral load monitoring for reducing HIV transmission.<h4>Design</h4>Mathematical model.<h4>Methods</h4>We developed a stochastic mathematical model representing the course of individual viral load, immunological response and survival in a cohort of 100 ...[more]

PMID: 22421243

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Project description:BackgroundThe United Nations' 95-95-95 (95% of people with HIV being aware of their diagnosis, 95% of those aware of their diagnosis being on treatment and 95% achieving viral suppression) target aims to reduce morbidity and mortality of HIV. However, with 60% of new HIV infections occurring in sub-Saharan Africa (SSA), achieving this target in the region is challenging. Viral load (VL) monitoring is the gold-standard approach of assessing treatment efficacy, and its implementation into national health systems is a global health priority if elimination of HIV as a public health threat is to be achieved by 2030. This systematic review aims to investigate VL monitoring outcomes in SSA, and to identify gaps and possible interventions to help nations meet their 2030 targets.MethodsA literature search of three electronic platforms (MEDLINE, EMBASE and Global Health) was undertaken from 1 January to 9 August 2024 to identify studies published in English and conducted in SSA. The primary outcome was the proportion of people living with HIV (PLHIV) on antiretroviral therapy (ART) with routine VL monitoring at the recommended time points (initially, 6 months, 12 months and annually). Secondary outcomes reported proportions of PLHIV who received routine VL monitoring who went on to complete the cascade of care after identified virological failure [enhanced adherence counselling (EAC), switch to second-line ART, and finally viral suppression].ResultsThe initial search identified 342 papers, of which 35 studies were included for narrative synthesis. Included studies reported on findings from 14 African countries and demonstrated extensive variation in rates of VL monitoring (range: 24.3-99.7%, mean: 63.8%). Results were more unfavourable in the latter steps of the viral load monitoring cascade, with a range of 0-88%, and a switch to second-line ART mean of 42% (range: 4.4-93%). Studies with additional support, and those with community-based models of care, had higher rates of VL testing and viral suppression.ConclusionsVL monitoring and management of virological failure are suboptimal in many SSA countries due to individual and health system-related challenges. Health system strengthening is vital to ensure the sustainability of HIV treatment programmes and the achievement of 95-95-95 targets by 2030.

Dataset Information

Viral load monitoring of antiretroviral therapy, cohort viral load and HIV transmission in Southern Africa: a mathematical modelling analysis.

Objectives

Design

Methods

Results

Conclusion

Publications

Viral load monitoring of antiretroviral therapy, cohort viral load and HIV transmission in Southern Africa: a mathematical modelling analysis.

Similar Datasets

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