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Preventing HIV in women in Africa
Get PDFHIV incidence is declining globally, but around half of all new infections are in sub-Saharan Africa—where adolescent girls and young women bear a disproportionate burden of new infections. Those who sell sex are at particularly high risk. Despite declining incidence rates and availability of effective biomedical prevention tools, we are not on track, globally or in Africa, to achieve UNAIDS 2025 prevention targets. For those at risk, interventions that strengthen their motivation, capabilities and access to all available HIV prevention technologies are critical—for adolescent girls and women in particular, but also for epidemic control more broadly. Exciting possibilities for scaling up new and highly effective prevention technologies are close, but delivery, implementation and financing models need to be developed and urgently evaluated, in partnership with communities, or these opportunities may be lost. Here, we discuss the evolving landscape of biomedical prevention technologies for women in Africa, their implementation and financing, as well as priorities for HIV prevention research in this setting.</p
Elevating larval source management as a key strategy for controlling malaria and other vector-borne diseases in Africa
Get PDFLarval source management (LSM) has a long history of advocacy and successes but is rarely adopted where funds are limited. The World Health Organization (WHO) guidelines on malaria prevention recommend the use of LSM as a supplementary intervention to the core vector control methods (insecticide-treated nets and indoor residual spraying), arguing that its feasibility in many settings can be limited by larval habitats being numerous, transient, and difficult to find or treat. Another key argument is that there is insufficient high-quality evidence for its effectiveness to support wide-scale implementation. However, the stagnation of progress towards malaria elimination demands that we consider additional options to the current emphasis on insecticidal commodities targeting adult mosquitoes inside homes. This letter is the result of a global, crossdisciplinary collaboration comprising: (a) detailed online expert discussions, (b) a narrative review of countries that have eliminated local malaria transmission, and (c) a mathematical modeling exercise using two different approaches. Together, these efforts culminated in seven key recommendations for elevating larval source management as a strategy for controlling malaria and other mosquito-borne diseases in Africa (Box 1). LSM encompasses the use of larvicide (a commodity) as well as various environmental sanitation measures. Together, these efforts lead to the long-term reduction of mosquito populations, which benefits the entire community by controlling both disease vector and nuisance mosquitoes. In this paper, we argue that the heavy reliance on large-scale cluster-randomized controlled trials (CRTs) to generate evidence on epidemiological endpoints restricts the recommendation of approaches to only those interventions that can be measured by functional units and deliver relatively uniform impact and, therefore, are more likely to receive financial support for conducting these trials. The explicit impacts of LSM may be better captured by using alternative evaluation approaches, especially high-quality operational data and a recognition of locally distinct outcomes and tailored strategies. LSM contributions are also evidenced by the widespread use of LSM strategies in nearly all countries that have successfully achieved malaria elimination. Two modelling approaches demonstrate that a multifaceted strategy, which incorporates LSM as a central intervention alongside other vector control methods, can effectively mitigate key biological threats such as insecticide resistance and outdoor biting, leading to substantial reductions in malaria cases in representative African settings. This argument is extended to show that the available evidence is sufficient to establish the link between LSM approaches and reduced disease transmission of mosquito-borne illnesses. What is needed now is a significant boost in the financial resources and public health administration structures necessary to train, employ and deploy local-level workforces tasked with suppressing mosquito populations in scientifically driven and ecologically sensitive ways. In conclusion, having WHO guidelines that recognize LSM as a key intervention to be delivered in multiple contextualized forms would open the door to increased flexibility for funding and aid countries in implementing the strategies that they deem appropriate. Financially supporting the scale-up of LSM with high-quality operations monitoring for vector control in combination with other core tools can facilitate better health. The global health community should reconsider how evidence and funding are used to support LSM initiatives.</p
Causes of HIV-related CNS infection in Cameroon, Malawi, and Tanzania: epidemiological findings from the DREAMM HIV-related CNS implementation study.
Get PDFBackgroundCNS infections cause approximately a third of HIV-related deaths. The Driving Reduced AIDS-Associated Meningo-encephalitis Mortality DREAMM study aimed to prospectively diagnose the aetiology of HIV-related CNS infection in five public hospitals in Cameroon, Malawi, and Tanzania.MethodsDREAMM was a multicentre, hybrid type-2 implementation science project. Adults (aged ≥18 years) presenting with a first episode of suspected CNS infection, who were HIV seropositive or willing to have an HIV test, were eligible for recruitment. Following implementation of the DREAMM model of care, we measured the prevalence of cryptococcal meningitis, tuberculous meningitis, bacterial meningitis, and cerebral toxoplasmosis and did a χ2 test to assess whether prevalence differed between countries. We also reported disease-specific mortality and Toxoplasma gondii seroprevalence.FindingsOf 356 participants with suspected CNS infection analysed at baseline, 269 (76%) were diagnosed as having a CNS infection. Of these, 202 (75%) had a confirmed diagnosis. Between Cameroon, Malawi, and Tanzania, the prevalence of the four main types of CNS infection differed (cryptococcal meningitis p=0·0014, bacterial meningitis p=0·0043, CNS tuberculosis p<0·0001, and toxoplasmosis p<0·0001). Cryptococcal meningitis (148 [55%] of 269) was the leading cause overall. The next most common causes were CNS tuberculosis in Tanzania (29 [29%] of 99) and bacterial meningitis in Malawi (15 [19%] of 80). In Cameroon, cerebral toxoplasmosis (39 [43%] of 90) was the leading cause followed by cryptococcal meningitis (36 [40%] of 90). For cryptococcal meningitis, all-cause 2-week mortality was 23% (34 of 147) and all-cause 10-week mortality was 45% (66 of 146).InterpretationWithin the study population, the aetiology of HIV-related CNS infection varied substantially between Malawi, Cameroon, and Tanzania. Additional prospective epidemiological data are needed to inform HIV programmes. 2-week cryptococcal meningitis mortality outcomes were similar to those of clinical trials. However, new interventions are urgently needed to sustain mortality reductions following hospital discharge.</p
Quantifying intra-urban socio-economic and environmental vulnerability to extreme heat events in Johannesburg, South Africa
No full textUrban populations face increasing vulnerability to extreme heat events, particularly in rapidly urbanising Global South cities where environmental exposure intersects with socioeconomic inequality and limited healthcare access. This study quantifies heat vulnerability across Johannesburg, South Africa, by integrating high-resolution environmental data with socio-economic and health metrics across 135 urban wards. We examine how historical urban development patterns influence contemporary vulnerability distributions using principal component analysis and spatial statistics. Environmental indicators (Land Surface Temperature (LST), vegetation indices, and thermal field variance) were combined with socioeconomic and health variables (including indicators on crowded dwellings and healthcare access, self-reporting of chronic diseases) in a comprehensive vulnerability assessment. Principal Component Analysis revealed three primary dimensions explaining 56.6% (95% CI: 52.4–60.8%) of the total variance: urban heat exposure (31.5%), health status (12.8%), and socio-economic conditions (12.3%). Built-up areas showed weak but significant correlations with heat indices (ρ = 0.28, p < 0.01), while higher poverty levels demonstrated moderate positive correlations with LST (ρ = 0.41, p < 0.001). The spatial analysis identified significant clustering of vulnerability (Global Moran's I = 0.42, p < 0.001), with distinct high-vulnerability clusters in historically disadvantaged areas. Alexandra Township showed the highest vulnerability(HVI score: 0.87, LST: 29.8 °C ± 0.4 °C, NDVI: 0.08 ± 0.02), with factors characterising the high vulnerability in that area including limited healthcare access and extreme heat exposure. Northern suburbs formed a significant low-vulnerability cluster (Mean HVI = 0.23 ± 0.07, p < 0.001), benefiting from greater vegetation coverage and better healthcare access. These findings demonstrate how historical planning decisions continue to shape contemporary environmental health risks, with vulnerability concentrated in areas of limited healthcare access and high extreme heat exposure. Results suggest the need for targeted interventions that address both environmental and social dimensions of heat vulnerability, particularly focusing on expanding healthcare access in identified hotspots and implementing community-scale green infrastructure in high-risk areas. This study provides an evidence-based framework for prioritising heat-resilience initiatives in rapidly urbanising Global South cities while highlighting the importance of addressing historical inequities in urban adaptation planning.</p
How maternal morbidities impact women’s quality of life during pregnancy and postpartum in sub-Saharan Africa and South Asia: A qualitative study
Get PDFMaternal morbidities present a major burden to the health and well-being of childbearing women. However, their impacts on women’s functional health are not well understood. This work aims to describe how maternal morbidities affect women’s quality of life (QoL) in pregnancy and the postpartum period . This qualitative study involved 118 pregnant and 135 postpartum women at six study sites in Kenya, Ghana, Zambia, Pakistan, and India. Data were collected between December 2023 and June 2024. Participants were selected via purposive sampling, with consideration of age, trimester, and time since delivery. A total of 23 focus group discussions with pregnant and late postpartum (≥6 months) participants and 48 in-depth interviews with early postpartum (≤6 weeks) participants were conducted using semi-structured guides. Data were analyzed using a collaborative, inductive, thematic approach. Four overarching themes were identified and were cross-cutting irrespective of continent or country: (1) physical and emotional challenges pose a barrier to daily activities; (2) lack of social support detracts from women’s QoL; (3) receipt of social support mitigates adverse impacts of maternal morbidities on QoL; and (4) economic challenges exacerbate declines in women’s QoL during pregnancy and postpartum. Physical and emotional morbidities related to childbearing severely limited women’s ability to complete daily tasks and adversely impacted their perceived QoL. Social and financial support from the baby’s father, family and/or in-laws, community members, and healthcare providers are important to mitigate the impacts of pregnancy and postpartum challenges on women’s health and well-being.</p
Establishing accountability and promoting rights: the WHO QualityRights contribution to mental health, recovery and community inclusion
Get PDFAttention to human rights as a central pillar of global mental health work has shifted from a focus on the right to healthcare to a deeper examination of the quality of care received, and to the way in which people with mental health conditions are treated in all aspects of life. The QualityRights programme is the World Health Organization’s flagship guidance for promotion of rights-based approaches to mental healthcare, and a means of holding service providers to account for quality of care provided. A recent evaluation of the QualityRights e-training package demonstrates promising impact on attitude change of participants, raising the prospect of an efficient scale-up of efforts to improve dignity in services and reduce stigma and discrimination.</p
Abstracts of the 26th International Workshop on Clinical Pharmacology of HIV, Hepatitis and other Antiviral Drugs 2025, 3-4 September 2025, Amsterdam, the Netherlands
No full textDiversity of Salmonella enterica isolates from urban river and sewage water in Blantyre, Malawi
Get PDFBACKGROUND: Salmonella enterica encompasses over 2,600 serovars, including several commonly associated with severe infection in humans. Salmonella is a major cause of sepsis in Africa; however, diagnosis requires clinical microbiology facilities. Environmental surveillance has the potential to play a role in Salmonella surveillance. METHODS: We undertook water-based environmental surveillance in Blantyre, Malawi, from 2018-2020, taking samples from rivers (87.9%), a sewage plant (8.85%) and other water sources (3.24%), isolating and storing 1,042 non-typhoidal Salmonella (NTS) isolates in this period. Of these, 341 NTS isolates were whole genome sequenced, genome quality was checked, duplicate genomes from any given sample were removed and core genome phylogeny was reconstructed. AMRFinder, PathogenWatch and SISTR were used to further investigate serovar, sequence type and antimicrobial resistance determinants. RESULTS: After quality checks, and removal of duplicate genomes, 270 NTS genomes remained for further analysis. Multiple Salmonella serovars associated with human infection were detected, of which S. Typhimurium (55/270 isolates) was the most common, including 44 of Sequence Type (ST) 313, a serovar commonly associated with severe invasive disease (iNTS). Six lineage 2 ST313 genomes possessed AMR genes predicting multidrug resistance (MDR), while 29 lineage 3 isolates contained no AMR predictive genes. PCR based detection of staG has been proposed as a diagnostic marker of S. Typhi; however, all eight genomes that contained staG identified as Salmonella enterica serovar Orion, raising concerns about the specificity of this marker as a monoplex for environmental surveillance of S. Typhi. DISCUSSION: The study identified diverse Salmonella serovars in the environment, including those reported to cause invasive disease, emphasizing the complex but potentially valuable contribution of implementing environmental surveillance for Salmonella in high burden areas lacking diagnostic microbiology capacity.</p
A Systematic Categorization of Performance Measures for Estimated Non-Linear Associations Between an Outcome and Continuous Predictors
Get PDFIn regression analysis, associations between continuous predictors and the outcome are often assumed to be linear. However, modeling the associations as non-linear can improve model fit. Many flexible modeling techniques, like (fractional) polynomials and spline-based approaches, are available. Such methods can be systematically compared in simulation studies, which require suitable performance measures to evaluate the accuracy of the estimated curves against the true data-generating functions. Although various measures have been proposed in the literature, no systematic overview exists so far. To fill this gap, we introduce a categorization of performance measures for evaluating estimated non-linear associations between an outcome and continuous predictors. This categorization includes many commonly used measures. The measures can not only be used in simulation studies, but also in application studies to compare different estimates to each other. We further illustrate and compare the behavior of different performance measures through some examples and a Shiny app. This article is categorized under: Statistical and Graphical Methods of Data Analysis > Modeling Methods and Algorithms.</p
