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Global, regional, and national burden of HIV/AIDS, 1990–2023, with the estimated burden attributable to intimate partner violence and forecasted impacts of funding cuts through 2030: results from the Global Burden of Disease Study 2023
(The Lancet HIV, 2026-08-18) GBD 2023 HIV Collaborators
Background
Despite a general improvement in the HIV burden over the past two decades, gendered social determinants including intimate partner violence (IPV) continue to affect women's vulnerability to HIV, which could be further exacerbated as resources dwindle over the coming years. Our study aimed to quantify recent trends in the HIV burden, the magnitude of the HIV burden associated with IPV, and the potential impact of declining financial support globally.
Methods
Using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023 framework, we estimated annual HIV incidence, prevalence, and mortality for 204 countries and territories from 1990 to 2023, disaggregated by age and sex. Input data included national HIV programme reports, population-based serosurveys, clinical and vital registration data, and systematically reviewed literature. Countries and territories were grouped according to the availability and completeness of HIV prevalence and mortality data, with tailored modelling approaches applied for each group. To characterise the potential contributions of IPV to the HIV burden, time series estimates of IPV prevalence by location and effect size estimates were combined to generate population attributable fractions of the HIV burden. To forecast future trends and assess the potential impact of reductions in development assistance for health, we used a non-parametric stochastic frontier approach to estimate how funding levels could affect antiretroviral therapy (ART) coverage. Adjustments in future ART coverage were integrated into our forecasts, altering projected rates of HIV-related incidence and mortality. We compared scenarios with and without funding cuts, quantifying the potential epidemiological effects of reduced ART availability by sex.
Findings
Between 2003 and 2023, the annual number of new HIV infections declined globally, from 2·85 million (95% uncertainty interval [UI] 2·76–2·96) to 2·06 million (1·88–2·29). Meanwhile, HIV-related deaths decreased from a peak of 1·71 million (1·61–1·83) in 2004 to 0·83 million (0·73–0·96) in 2023. The number of people living with HIV rose from 26·3 million (25·5–27·3) in 2003 to 42·4 million (40·3–44·4) in 2023, reflecting improved survival associated with ART expansion. Although females continued to have higher prevalence of HIV than males in 2023 (23·4 million [22·2–24·6] vs 19·1 million [17·6–20·5]), the gap in incidence between females and males has substantially declined. Regionally, sub-Saharan Africa had the greatest declines in both incidence (64·3%; 58·0–68·6) and mortality (74·6%; 70·4–78·5) between 2003 and 2023, while central Europe, eastern Europe, and central Asia recorded the highest increases in incidence rates (232·1%; 146·5–299·1) and mortality rates (37·8%; 31·2–45·5) during this period. IPV was associated with an estimated 10·7% (1·6–20·4) of HIV-related deaths among females aged 15 years and older globally in 2023, corresponding to 40 700 (6400–80 600) deaths, with the highest population attributable fractions observed in Oceania (17·4%; 2·8–33·1), central sub-Saharan Africa (14·2%; 2·1–29·4), and eastern sub-Saharan Africa (13·2%; 2·0–25·3). Forecasts indicate that funding reductions could decrease ART coverage by 8·1% globally between 2025 and 2030, resulting in approximately 1·6 million new HIV infections among females and 1·3 million new HIV infections among males, alongside 790 600 and 670 600 HIV-related deaths, respectively. These impacts are primarily concentrated in sub-Saharan Africa.
Interpretation
Despite two decades of substantial progress, the global HIV response remains highly sensitive to gendered social determinants and funding stability. The potential contribution of IPV to HIV-related mortality among women underscores the need for integrated interventions that address violence prevention and post-violence care alongside HIV treatment. The projected effects of funding cuts—millions of additional infections and deaths—highlight the fragility of the gains achieved and the urgent need to protect HIV financing. Achieving and sustaining the UNAIDS 2030 targets will require renewed investment, gender-responsive programming, and resilient health systems capable of providing equitable access to care.
Funding
Gates Foundation and the US National Institute of Allergy and Infectious Diseases.
Insecticide susceptibility and knockdown resistance (Kdr) mutations (F1534C and V1016I) in Aedes aegypti populations from Dar es Salaam, Tanzania
(Springer and Nature, 2026-08-02) Tenywa, Frank; Hälg, Silvan; Haji, Makame; Moore, Jason; Dogan, Osward; Haruna, Mapipi; Müller, Pie; Moore, Sarah
Background
Dengue, Zika and chikungunya are Aedes-borne arboviruses that pose a major global public health threat. In the absence of effective treatments or universally available vaccines, disease control in sub-Saharan Africa relies primarily on insecticidal vector control. However, sustained insecticide application imposes selection pressure for insecticide resistance that compromises intervention effectiveness. This study assessed the insecticide resistance profile and knockdown resistance of Aedes aegypti populations in Dar es Salaam, Tanzania.
Methods
Phenotypic resistance of Ae. aegypti was evaluated using WHO-recommended adulticide and larvicide susceptibility bioassays at discriminating concentrations. F1 progeny derived from wild Ae. aegypti larvae were used for the tests. In adulticide bioassays, groups of 25 female Ae. aegypti were exposed for 1 h to insecticide-treated WHO susceptibility test papers. Larvicide bioassays exposed 25 third- and fourth-instar larvae to a larvicide based on Bacillus thuringiensis israelensis (Bti) or temephos for 24 h in 200 ml of water. Mosquito mortality was recorded 24 h post-exposure. Genotypic resistance was assessed using DNA extracted from phenotyped mosquitoes. The extracted DNA was screened for knockdown resistance (Kdr) mutations using diagnostic quantitative polymerase chain reaction (qPCR) assays.
Results
Aedes aegypti populations from Ilala and Temeke districts of Dar es Salaam demonstrated phenotypic resistance to Pyrethroid: permethrin, deltamethrin, alpha-cypermethrin, lambda-cyhalothrin, and organochlorine, with adult mortality rates below 20% and 5%, respectively, while remaining susceptible to organophosphates and carbamates. In Kinondoni, resistance was observed across all classes except carbamates, and pre-exposure to piperonyl butoxide (PBO) increased pyrethroids mortality to an average of 40%. The LD50 and LD90 values for Bti and temephos showed resistance ratios (RR) below 5. The F1534C mutation was detected across all study districts; Ilala (77%, n = 77), Kinondoni (90%, n = 90) and Temeke (83%, n = 83), while low frequencies were observed for V1016I mutation.
Conclusions
Aedes aegypti populations from Dar es Salaam show widespread resistance to pyrethroids, and organochlorines. There was evidence of metabolic involvement suggested by partial restoration of susceptibility to pyrethroids through pre-exposure to PBO. A twofold increase in LD90 relative to the susceptible reference strain for Bti and temephos indicates no evidence of resistance, although continued monitoring is warranted to detect potential shifts in susceptibility.
Harnessing geospatial and machine learning technologies to simulate ecosystem services and greenhouse gas emissions in a dynamic watershed system of Haramaya Lake, Ethiopia
(Springer and Nature, 2026-08-14) Mosisa, Gemechis; Akuku, James; Mwembe, Abel; Mereba, Firaol; Ngazi, Veneranda; Negash, Birhanu; Kabuyene Kakundane; Feyisa, Gudina
The increased land use change, coupled with weak regulatory mechanisms, has increased the deterioration of Haramaya lake Watershed, thus contributing to ecosystem service value (ESV) decline and greenhouse gas (GHG) emissions. However, the information about the observed and predicted impacts of land use changes on the ESV changes and GHG emissions in the Haramaya Lake Watershed is limited. This study thus followed an interdisciplinary approach, integrating three pressing global change factors: land use/land cover (LULC) change, ESV changes, and GHG emissions to understand their historical and future impacts on Haramaya Lake Watershed using machine learning. Support Vector Machine (SVM) algorithm was used for historical LULC change analysis (1985–2024) and a machine learning-based Artificial Neural Network (ANN) was employed for simulation (2063). The ESVs changes were evaluated using the benefit transfer method based on the LULC data for the study periods and corresponding modified ESV coefficients derived from empirical studies. To estimate GHG emissions, the study followed the Inter-governmental Panel on Climate Change’s (IPPC) National GHG Inventories guideline. The results revealed a significant LULC shift between 1985 and 2024, characterized by a marked expansion of Khat (+ 9.98%) and built-up area (+ 5.03%) at the expense of cropland (-10.99%) and vegetation (-5.45%). Under a business-as-usual scenario simulated by the validated ANN model, these pressures are projected to continue, with cropland expanding to cover 45.22% and built-up area 20.22% of the watershed by 2063. The model predicts a decline in the wetland from 5.63% to 4.59%. The overall ESV was increased by 2.5% between 1985 and 2024, but projected to decline by 41.95% by 2063. The carbon sequestration capacity of Haramaya Lake Watershed exhibited a declining trend. Except for vegetation land use class, other land use types primarily contributed and projected to contribute to carbon emissions. The results suggest immediate implementation of integrated watershed management strategies, including land use zoning, sustainable agricultural practices, and alternative livelihood strategies.
Influence of coffee-derived phenolic compounds, initial loading, and biochar on anaerobic digestion of coffee pulp
(Elsevier Ltd., 2026-07-26) Said, Seleman; Ghofrani-Isfahani, Parisa; Machunda, Revocatus; Mshandete, Anthony; Kivaisi, Amelia; Angelidaki, Irini
Coffee pulp (CP), a by-product of wet coffee-cherry processing, contains organic matter suitable for biogas production through anaerobic digestion (AD). However, its high phenolic content may influence methane production. Batch digestion assays using whole CP, individual phenolic compounds [5-O-caffeoylquinic acid (5-CQA) and caffeic acid (CFA)], and CP phenolic extract were conducted under mesophilic conditions. Co-digestion experiments with Avicel microcrystalline cellulose and ethanol were performed to evaluate phenolic interactions with degradable substrates. Increasing initial loading (2–12 g VS/L) reduced methane yields from CP by approximately 20%, due to substrate overloading and transient volatile fatty acid accumulation, whereas lower loadings (2–4 g VS/L) supported rapid and stable methane production at inoculum-to-substrate ratios ≥ 2.0:1. Both 5-CQA and CFA were anaerobically biodegradable and contributed to methane formation during co-digestion. Ethanol digestion exhibited high tolerance to phenolic compounds, showing additive or synergistic interactions, whereas cellulose digestion was more sensitive, with prolonged lag phases and increasing antagonistic effects, particularly in the presence of CFA. CP phenolic extract produced lower methane yields than comparable systems supplemented with pure 5-CQA, indicating that inhibition resulted from combined effects of multiple phenolic constituents rather than individual compounds. At the tested dosage of 5 g/L, woody green-waste biochar did not improve methane production across the evaluated CP loadings, suggesting that the dominant process constraints were not alleviated under the investigated conditions. Overall, methane production under batch conditions was governed primarily by initial loading, phenolic composition, and substrate type, whereas biochar addition at the tested dosage had no effect.
Spatiotemporal patterns of ambient NO2 and NO pollution in Kigali Rwanda
(Springer and Nature, 2026-08-05) Karekezi, Pacifique; Kyeremateng, Kate; Lange, Carissa; Umutoni, Chantal; Kubwimana, Jean; Nimo, James; Wang, Jiayuan; Mottey, Barbara; Gahungu, Paterne; Mirau, Silas; Nyinawumuntu, Claudette; Niyizirugero, Samson; Hakizimana, Pie-Celestin; Mbalawata, Isambi; Ezzati, Majid; Hughes, Allison; Arku, Raphael
Kigali, like many cities in sub-Saharan Africa, faces rapid urban growth alongside the need to manage air pollution and protect public health. Despite its policy efforts, systematic data on nitrogen oxides (NOx: NO2 and NO), key indicators of combustion-related pollution, have been limited. We applied a standardized protocol to characterize city-scale spatial and temporal patterns of NOx across Kigali. Between November 2022 and December 2023, we collected weekly integrated NO2 and NO samples (n = 630 each) at 130 sites representing diverse land-use types. NO2 concentrations ranged from 1.3 to 61.9 µg/m3 (mean 13.9 µg/m3), with annual-equivalent frequently exceeding the WHO annual guideline (10 µg/m3) in urban areas. Exceedances occurred in 39% of sparsely residential, 89% of commercial/industrial, and 99% of densely populated residential sites. NO2 concentrations were significantly higher in urban versus rural areas (18.2 vs. 6.3 µg/m3), near major roads (19.9 vs. 11.6 µg/m3), and at lower elevations (15.4 vs. 9.0 µg/m3). The highest levels were observed in the densely populated districts of Kicukiro and Nyarugenge. Overall, NO2 and NO exhibited strong spatial gradients related to land use, traffic, population density, and topography, highlighting the importance of targeted urban planning and air quality management in rapidly growing cities.