The Effect of 90-90-90 on HIV-1 Incidence and Mortality in the Kingdom of Eswatini

Abstract

Background: The rapid scale-up of antiretroviral therapy (ART) over the last decade has sparked considerable debate as to whether universal test and treat (UTT) can end the HIV epidemic in sub-Saharan Africa (SSA). Methods: Using the Kingdom of Eswatini as a case study, we developed a network transmission model, calibrated to capture age and gender-specific gaps in the scale-up of ART, to estimate the impact of attaining and surpassing the 90-90-90 treatment targets on HIV incidence and mortality. We compared different ART coverage scenarios to estimate reductions in incidence and mortality over time and to evaluate the potential to drive annual incidence below an epidemic control threshold of 0.1%. Findings: ART scale-up reduced HIV incidence by 43.5% (95% credible interval, 39.7 - 46.4%) and HIV mortality by 56.2% (95% CI, 54.1 - 58.9%) among adults 15-49 years of age between 2010 and 2016, with larger reductions in incidence among men and mortality among women. Holding 2016 ART coverage levels by age and gender, adult HIV incidence would fall to 1.1% (95% CI: 0.87 - 1.3%), 2.0% (95% CI: 1.5 - 2.5%) among women, and 0.9% (95% CI: 0.7 - 1.2%) among men by 2030. Achieving the 90-90-90 targets by age and gender would further reduce incidence in individuals 15-24 years of age, 17.4% (95% CI, 7.3 - 26.1%) additional incidence reduction between 2016 and 2013, with only modest additional reductions in adults overall. Achieving 100% ART initiation, an upper bound of treatment effect, would reduce adult HIV incidence to 0.7% (95% CI: 0.6 - 0.9%) by 2030 and 0.5% (95% CI: 0.3 - 0.6%) by 2050. Interpretation: Scale-up of ART over the last decade has already contributed to substantial reductions in HIV incidence and mortality. Focused ART targeting would further reduce incidence, especially in younger individuals, but even the most aggressive treatment campaigns would be insufficient to end the epidemic in high-burden settings without a renewed focus on expanding preventive measures. Funding Statement: Support provided from the Global Good Fund and the Bill and Melinda Gates Foundation. Declaration of Interests: All authors declare no competing interests. Ethics Approval Statement: Not required.