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Progress in HIV Epidemic Control in Six Sub-Saharan African Countries: Findings from Sequential Population Surveys
17 Pages Posted: 15 May 2025
More...Abstract
Background: Progress in confronting the HIV epidemic has been noted in sub-Saharan Africa; however, measuring such progress is an important priority. We explored the use of various indicators to assess momentum in six high-burden countries in sub-Saharan Africa.
Methods: We analyzed two rounds of Population-based HIV Impact Assessment (PHIA) surveys (Round 1: 2016–17; Round 2: 2020–23) among adults ≥ 15 years in Eswatini, Lesotho, Malawi, Tanzania, Uganda, and Zimbabwe. Weighted estimates (95% CI) were generated for HIV prevalence, annual incidence, viral-load suppression (VLS < 1,000 copies/mL), advanced HIV disease (AHD; CD4 < 200 cells/µL), incidence-prevalence ratio (IPR), and incidence-to-low CD4+ ratio (ICR). Round-to-round differences were tested with Poisson regression (α = 0.05).
Findings: Population VLS improved substantially in every country, rising from 52–73% to 75–89%. HIV prevalence fell significantly in Eswatini, Lesotho, Malawi, and Tanzania, but not in Uganda or Zimbabwe. Annual incidence declined significantly only in Lesotho (1.10% → 0.50%; p = 0.03). IPR decreased in five settings and fell below the ≤ 3% epidemic-control benchmark in Lesotho (2.1%), Malawi (2.5%), and Eswatini (2.5%); Zimbabwe remained at 3.0%. AHD prevalence decreased universally (7–13% → 4–9%), yet ICR trends diverged: it fell in Lesotho (10.2 → 7.6) and Malawi (4.1 → 3.6), but rose in Eswatini (15.9 → 16.3), Tanzania (2.3 → 2.8), Uganda (4.5 → 5.5), and Zimbabwe (3.2 → 4.3).
Interpretation: Impressive gains were noted in diagnosis and treatment across all, but were not uniformly associated with transmission reductions. The scale-up of testing and therapy has resulted in improved VLS and a decrease in AHD, yet heterogeneous incidence and increasing ICRs expose gaps in primary prevention and early diagnosis. Monitoring IPR and ICR alongside diagnosis and treatment cascade metrics offers a comprehensive view of epidemic dynamics and can guide efforts towards accelerated HIV control progress.
Keywords: HIV, Epidemic Control, UNAIDS 95-95-95 Targets, HIV Incidence, Incidence-Prevalence Ratio (IPR), Incidence-Low CD4+ Ratio (ICR), Population Surveys, PHIA, Sub-Saharan Africa
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