Temporal trends of population viral suppression in the context of Universal Test and Treat: the ANRS 12249 TasP trial in rural South Africa

Joseph Larmarange (1, 2) , Mamadou Diallo (3, 4) , Nuala Mcgrath (5) , Collins Iwuji (6) , Mélanie Plazy (7) , Rodolphe Thiébaut (7) , Frank Tanser (8) , Till Bärrnighausen (9) , Joanna Orne‐gliemann (7) , Deenan K Pillay (10) , Francois Dabis (7)

1 CEPED - UMR_D 196 - Centre population et développement
2 SAGESUD - ERL Inserm U1244 - Santé, vulnérabilités et relations de genre au sud
3 CEPED - UMR_D 196 - Centre population et développement
4 SAGESUD - ERL Inserm U1244 - Santé, vulnérabilités et relations de genre au sud
5 LSHTM - London School of Hygiene and Tropical Medicine
6 BSMS - Brighton and Sussex Medical School
7 ISPED - Institut de Santé Publique, d'Epidémiologie et de Développement
8 AHRI - Africa Health Research Institute [Durban/Mtubatuba]
9 Harvard School of Public Health
10 UCL - University College of London [London]

Introduction: The universal test-and-treat (UTT) strategy aims to maximize population viral suppression (PVS), that is, the proportion of all people living with HIV (PLHIV) on antiretroviral treatment (ART) and virally suppressed, with the goal of reducing HIV transmission at the population level. This article explores the extent to which temporal changes in PVS explain the observed lack of association between universal treatment and cumulative HIV incidence seen in the ANRS 12249 TasP trial conducted in rural South Africa. Methods: The TasP cluster-randomized trial (2012 to 2016) implemented six-monthly repeat home-based HIV counselling and testing (RHBCT) and referral of PLHIV to local HIV clinics in 2 9 11 clusters opened sequentially. ART was initiated according to national guidelines in control clusters and regardless of CD4 count in intervention clusters. We measured residency status, HIV status, and HIV care status for each participant on a daily basis. PVS was computed per cluster among all resident PLHIV (≥16, including those not in care) at cluster opening and daily thereafter. We used a mixed linear model to explore time patterns in PVS, adjusting for sociodemographic changes at the cluster level. Results: 8563 PLHIV were followed. During the course of the trial, PVS increased significantly in both arms (23.5% to 46.2% in intervention, +22.8, p < 0.001; 26.0% to 44.6% in control, +18.6, p < 0.001). That increase was similar in both arms (p = 0.514). In the final adjusted model, PVS increase was most associated with increased RHBCT and the implementation of local trial clinics (measured by time since cluster opening). Contextual changes (measured by calendar time) also contributed slightly. The effect of universal ART (trial arm) was positive but limited. Conclusions: PVS was improved significantly but similarly in both trial arms, explaining partly the null effect observed in terms of cumulative HIV incidence between arms. The PVS gains due to changes in ART-initiation guidelines alone are relatively small compared to gains obtained by strategies to maximize testing and linkage to care. The achievement of the 90-90-90 targets will not be met if the operational and implementational challenges limiting access to care and treatment, often context-specific, are not properly addressed. Clinical trial number: NCT01509508 (clinicalTrials.gov)/DOH-27-0512-3974 (South African National Clinical Trials Register).

Keywords: South Africa; population health; retention in care; sustained viral suppression; antiretroviral therapy; HIV

Domains: Life Sciences [q-bio]; Santé publique et épidémiologie

Joseph Larmarange, Mamadou Diallo, Nuala Mcgrath, Collins Iwuji, Mélanie Plazy, et al.. Temporal trends of population viral suppression in the context of Universal Test and Treat: the ANRS 12249 TasP trial in rural South Africa. Journal of the International AIDS Society, 2019, 22 (10), ⟨10.1002/jia2.25402⟩. ⟨hal-03161847v3⟩