Hmwe Hmwe Kyu’s research while affiliated with University of Washington and other places

Background: Eliminating HIV vertical transmission (VT) and is a global priority. Estimates of paediatric HIV infections are commonly derived through mathematical models relying on rates of VT stratified by maternal immunological and treatment status from literature, namely the UNAIDS-supported Spectrum AIDS Impact Module (Spectrum-AIM) to assess progress towards eliminating VT. Default VT probabilities were last updated in 2018, since then there have been substantial changes to service delivery and ART regimens. Methods: We aimed to (1) update the systematic review of VT probabilities by maternal status compatible with Spectrum-AIM, (2) conduct a meta-regression to systematically pool studies to estimate VT probabilities with statistical uncertainty, and (3) assess determinants of VT, including maternal viral load. We searched PubMed, Embase, Global Health Database, WHO Global Index Medicus, CINAHL Complete, and Cochrane CENTRAL for peer-reviewed articles in English from all geographic regions with data on VT from randomized controlled trials, cohort studies, or observational studies. We excluded sources that did not stratify VT by maternal treatment or immunological status. We fit four meta-regression models to produce VT probability estimates compatible with stratifications used in Spectrum-AIM and assessed how updated VT probabilities estimated new paediatric infections compared to default parameters in Spectrum-AIM. We conducted subgroup analyses to assess how study inclusion affected model estimates. Finally, we fit a meta-regression model to assess ART class and initiation timing on viral load suppression at delivery. Findings: The updated systematic review identified 24 new studies published between January 2018 and February 2024. Combined with previous review data, 110 studies were included in the meta-regression analysis. Estimates were broadly consistent with previous reviews. For women not receiving PMTCT, the odds of perinatal transmission decreased by 0.20 (0.16-0.25) for each 100 mm3 increase in median CD4 of the study population. Among women on ART during pregnancy, each additional week on ART before delivery reduced the odds of VT by 5.6% (4.3%-6.8%). ART regimen class affected VT probability; the odds ratio of perinatal VT among WLHIV who initiated an INSTI-based regimen versus a NNRTI-based regimen 20 weeks before delivery was 0.355 (0.140-0.898). However, this effect was confounded by study region. Viral load suppression at delivery was significantly lower among women who started ART late during pregnancy (p=0.02), but did not significantly differ by ART class (p>0.05). Interpretation: Vertical transmission rates vary substantially according to maternal immunological stage, prophylactic regimen, and timing of treatment initiation. Time of initiation on ART before delivery was strongly associated with viral load suppression at delivery. Our estimates and their uncertainty can be used in Spectrum-AIM to produce estimates of paediatric incidence to inform funding and monitor progress towards eliminating VT. Funding: National Institutes of Health, UNAIDS, and the Medical Research Council

Background As set out in Sustainable Development Goal 3.3, the target date for ending the HIV epidemic as a public health threat is 2030. Therefore, there is a crucial need to evaluate current epidemiological trends and monitor global progress towards HIV incidence and mortality reduction goals. In this analysis, we assess the current burden of HIV in 204 countries and territories and forecast HIV incidence, prevalence, and mortality up to 2050 to allow countries to plan for a sustained response with an increasing number of people living with HIV globally. Methods We used the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 analytical framework to compute age-sex-specific HIV mortality, incidence, and prevalence estimates for 204 countries and territories (1990–2021). We aimed to analyse all available data sources, including data on the provision of HIV programmes reported to UNAIDS, published literature on mortality among people on antiretroviral therapy (ART) identified by a systematic review, household surveys, sentinel surveillance antenatal care clinic data, vital registration data, and country-level case report data. We calibrated a mechanistic simulation of HIV infection and natural history to available data to estimate HIV burden from 1990 to 2021 and generated forecasts to 2050 through projection of all simulation inputs into the future. Historical outcomes (1990–2021) were simulated at the 1000-draw level to support propagation of uncertainty and reporting of uncertainty intervals (UIs). Our approach to forecasting utilised the transmission rate as the basis for projection, along with new rate-of-change projections of ART coverage. Additionally, we introduced two new metrics to our reporting: prevalence of unsuppressed viraemia (PUV), which represents the proportion of the population without a suppressed level of HIV (viral load <1000 copies per mL), and period lifetime probability of HIV acquisition, which quantifies the hypothetical probability of acquiring HIV for a synthetic cohort, a simulated population that is aged from birth to death through the set of age-specific incidence rates of a given time period. Findings Global new HIV infections decreased by 21·9% (95% UI 13·1–28·8) between 2010 and 2021, from 2·11 million (2·02–2·25) in 2010 to 1·65 million (1·48–1·82) in 2021. HIV-related deaths decreased by 39·7% (33·7–44·5), from 1·19 million (1·07–1·37) in 2010 to 718 000 (669 000–785 000) in 2021. The largest declines in both HIV incidence and mortality were in sub-Saharan Africa and south Asia. However, super-regions including central Europe, eastern Europe, and central Asia, and north Africa and the Middle East experienced increasing HIV incidence and mortality rates. The number of people living with HIV reached 40·0 million (38·0–42·4) in 2021, an increase from 29·5 million (28·1–31·0) in 2010. The lifetime probability of HIV acquisition remains highest in the sub-Saharan Africa super-region, where it declined from its 1995 peak of 21·8% (20·1–24·2) to 8·7% (7·5–10·7) in 2021. Four of the seven GBD super-regions had a lifetime probability of less than 1% in 2021. In 2021, sub-Saharan Africa had the highest PUV of 999·9 (857·4–1154·2) per 100 000 population, but this was a 64·5% (58·8–69·4) reduction in PUV from 2003 to 2021. In the same period, PUV increased in central Europe, eastern Europe, and central Asia by 116·1% (8·0–218·2). Our forecasts predict a continued global decline in HIV incidence and mortality, with the number of people living with HIV peaking at 44·4 million (40·7–49·8) by 2039, followed by a gradual decrease. In 2025, we projected 1·43 million (1·29–1·59) new HIV infections and 615 000 (567 000–680 000) HIV-related deaths, suggesting that the interim 2025 targets for reducing these figures are unlikely to be achieved. Furthermore, our forecasted results indicate that few countries will meet the 2030 target for reducing HIV incidence and HIV-related deaths by 90% from 2010 levels. Interpretation Our forecasts indicate that continuation of current levels of HIV control are not likely to attain ambitious incidence and mortality reduction targets by 2030, and more than 40 million people globally will continue to require lifelong ART for decades into the future. The global community will need to show sustained and substantive efforts to make the progress needed to reach and sustain the end of AIDS as a public threat. Funding The Bill & Melinda Gates Foundation and the National Institute of Allergy and Infectious Diseases.