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    Open Access
    Oral PrEP use among pregnant or parenting young women in South Africa: evidence from a large community-based implementation study
    (2026) Chen-Charles, Jenny Davey, Dvora J. Rousseau, Elzette Little, Francesca Toska, Elona Mathola, Ntombovuyo Macdonald, Pippa Vanto, Onesimo Wallace, Melissa Bekker, Linda-Gail; Davey, Dvora J; Rousseau, Elzette; Little, Francesca; Toska, Elona; Mathola, Ntombovuyo; Macdonald, Pippa; Vanto, Onesimo; Wallace, Melissa; Bekker, Linda-Gail, Melissa
    Abstract Background The risk of HIV acquisition is heightened during pregnancy and early parenthood with the additional risk of vertical HIV transmission. While recent studies have improved our understanding of PrEP use among pregnant and breastfeeding women, further evidence is needed to inform the design of interventions that support sustained use, especially among young women who are pregnant or parenting. Methods We analysed data from young women aged 15–29 years who initiated PrEP in an implementation study (FastPrEP) in Cape Town, South Africa. Logistic regression was used to examine the association between pregnancy or parenting status (≥ 1 living child) and PrEP discontinuation at 1- and 4-months post-initiation, based on pharmacy refill data. The primary exposure was currently pregnant or having a child (vs. not); secondary analyses stratified by age (15–24 vs. 25–29 years) among women who were pregnant/parenting. Models were adjusted for age and hypothesised explanatory factors were included in sensitivity analysis: service delivery location, contraceptive use, HIV risk perception, and relationship status. Results Between August 2022 and June 2024 n = 4,876 young women initiated PrEP; 44% were pregnant/parenting (of which 10% were pregnant), and the median age was 21.6 years (IQR:18–25). At 1-month, women who were pregnant/parenting had higher odds of PrEP discontinuation (aOR:1.30, 95% CI:1.14–1.49). At 4-months this relationship persisted (aOR:1.41, 95% CI:1.12–1.78) compared with non-pregnant/parenting women. Among those pregnant/parenting, younger women (15–24 years) had higher odds of discontinuation at 1-month (aOR:1.31, 95% CI:1.08–1.58) and 4-months (aOR:1.41, 95%CI:1.02–1.96) compared to women aged 25–29. In the fully adjusted multivariable model, receiving PrEP in mobile clinics (aOR:0.71, 95% CI:0.61–0.82) vs. government clinics was associated with lower odds of early discontinuation. Conclusion Young women who are pregnant/parenting face elevated risk of early PrEP discontinuation. Differentiated, life-stage and youth-responsive interventions, such as counselling, partner involvement, and integration with maternal and child health, or sexual and reproductive health services, are critical to improving PrEP persistence among this priority population. This population should be prioritised in the rollout of long-acting PrEP formulations, which may better align with their needs and reduce the burden of daily adherence.
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    Open Access
    The tumor microenvironment in tumorigenesis and therapy resistance revisited
    (2023) Dzobo, Kevin; Senthebane, Dimakatso A; Dandara, Collet
    Tumorigenesis is a complex and dynamic process involving cell-cell and cell-extracellular matrix (ECM) interactions that allow tumor cell growth, drug resistance and metastasis. This review provides an updated summary of the role played by the tumor microenvironment (TME) components and hypoxia in tumorigenesis, and highlight various ways through which tumor cells reprogram normal cells into phenotypes that are pro-tumorigenic, including cancer associated- fibroblasts, -macrophages and -endothelial cells. Tumor cells secrete numerous factors leading to the transformation of a previously anti-tumorigenic environment into a pro-tumorigenic environment. Once formed, solid tumors continue to interact with various stromal cells, including local and infiltrating fibroblasts, macrophages, mesenchymal stem cells, endothelial cells, pericytes, and secreted factors and the ECM within the tumor microenvironment (TME). The TME is key to tumorigenesis, drug response and treatment outcome. Importantly, stromal cells and secreted factors can initially be anti-tumorigenic, but over time promote tumorigenesis and induce therapy resistance. To counter hypoxia, increased angiogenesis leads to the formation of new vascular networks in order to actively promote and sustain tumor growth via the supply of oxygen and nutrients, whilst removing metabolic waste. Angiogenic vascular network formation aid in tumor cell metastatic dissemination. Successful tumor treatment and novel drug development require the identification and therapeutic targeting of pro-tumorigenic components of the TME including cancer-associated- fibroblasts (CAFs) and -macrophages (CAMs), hypoxia, blocking ECM-receptor interactions, in addition to the targeting of tumor cells. The reprogramming of stromal cells and the immune response to be anti-tumorigenic is key to therapeutic success. Lastly, this review highlights potential TME- and hypoxia-centered therapies under investigation.
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    Open Access
    Parenting programs for adolescent parents: a mixed methods systematic review of global interventions and evidence gaps
    (2025) Morse, Katherine; Martin, Mackenzie; Kruger, Robyn; Tatham, Claire
    issue, particularly in low- and middle-income countries, and is associated with health, social, and economic challenges for both mothers and children. Although parenting programs improve outcomes globally, there is a critical gap in tailored interventions for adolescent parents. This mixed methods systematic review aimed to address these gaps by conducting a global search of parenting programs designed or adapted for adolescent parents and making recommendations for future intervention development and research. The review examined participant characteristics, program characteristics and components, intervention results, and study quality. Thirty-six studies published between 2010 and 2024 were included, representing 34 unique samples. Most studies were from high-income countries, limiting generalizability, and only nine were rated as high-quality. Existing programs were almost entirely face-to-face, highlighting a gap in hybrid or app-based delivery. Additionally, there was a substantial lack of qualitative research exploring adolescent parenting needs and experiences. Overall, the findings indicate an urgent need for further development and evaluation of parenting programs for adolescents, particularly those implementable in low-resource settings, and for improved research quality to build an evidence base for effective, scalable interventions for this vulnerable population.
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    The role of market-based instruments that use existing markets to promote energy efficiency in South African industry
    (2011) Cargill, Judith Greer; Paterson, Alexander
    South Africa faces significant environmental challenges in relation to greenhouse gas (GHG) emissions mainly caused by the use of fossil fuels to provide energy coupled with the relatively inefficient nature of the South African energy sector. In addition the country now faces electricity supply constraints as evidenced by the electricity crisis in 2008. Industrial energy consumption forms a large component of the energy sector in South Africa. Therefore, there is significant scope for improved energy efficiency in industry to reduce greenhouse gas emissions and electricity supply constraints. Market-based instruments (MBIs) are being increasingly used to drive environmental improvement globally and in South Africa and provide a potentially powerful tool to promote domestic industrial energy efficiency. This dissertation evaluates the current array of MBIs that use existing markets to promote industrial energy efficiency in South Africa. The MBIs identified in this regard are the additional investment and energy efficiency allowances available under s12I and s12L of the Income Tax Act 58 of 1962, the electricity levy implemented under the Customs and Excise Act 91 of 1964, Eskom’s Demand Side Management (DSM) programme and NERSA’s proposed Cogeneration Feed-in Tariff (COFIT) programme. The latter three MBIS are incorporated into the recent attempt to make electricity prices more ‘cost reflective’ along with Renewable Energy Feed-in Tariff (REFIT) costs and the cost of capital to fund the new build programme. The main shortcoming of this range of MBIs is the failure to cover energy products such as coal and fuel oil as the main focus has been on electricity pricing to date. Energy–carbon taxes have been used successfully in Europe to drive industrial energy efficiency and reduce GHG. Drawing on the experience of the European Council directive 2003/96/EC of 27 October 2003 Restructuring the Community Framework for the Taxation of Energy Products and Electricity and the carbon tax options described in the National Treasury Discussion Paper Reducing Greenhouse Gas Emissions: The Carbon Tax Option (2010) there may be an opportunity for South Africa to extend the current array of MBIs to include a similar energy-carbon tax.
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    Genetics of Waardenburg Syndrome in Africa: A Systematic Review
    (2025-12-22) Aboagye, Elvis Twumasi; Wonkam, Ramses Peigou; de Kock, Carmen; Dandara, Collet; Wonkam, Ambroise
    Waardenburg syndrome (WS) represents a group of genetic conditions characterized by auditory and pigmentation defects. Pathogenic variants in PAX3, MITF, SOX10, EDN3, EDNRB, SNAI2, and KITLG genes have been associated with WS across multiple populations; a comprehensive study of WS in Africa has not yet been reported. We conducted a systematic review of clinical expressions and genetics of WS across Africa. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed, and the study protocol was registered on PROSPERO, the International Prospective Register of Systematic Reviews (2025 CRD420250655744). A literature search was performed on Google Scholar, PubMed, Scopus, Directory of Open Access Journals (DOAJ), Global Index Medicus, African-Wide Information, ScienceDirect, Connecting Repositories (CORE), and the Web of Science databases. We reviewed a total of 15 articles describing 84 WS cases, which showed no gender bias and a mean age at reporting of 17.5 years. Congenital, sensorineural, and profound hearing loss was described in most cases (66.7%; n = 56/84). WS type 2 (WS2), with characteristically no dystopia canthorum, is the predominant subtype (36.9%; n = 31/84). Pathogenic variants in four WS known genes, i.e., PAX3 (13 families), SOX10 (7 families), EDNRB (4 families), and EDN3 (1 family), were reported in Morocco, Tunisia, and South Africa. One candidate gene (PAX8) was described in one family in Ghana. Two non-syndromic hearing loss (NSHL) genes (BDP1 and MYO6) were reported in two separate families in South Africa, suggesting a possible phenotypic expansion. The highest number of WS cases was described in South Africa (38.1%; n = 32/84) and Tunisia (26.2%; n = 22/84). Gene variants were missense (27/43), deletion (7/43), splicing (5/43), nonsense (2/43), indel (1/43), and duplication (1/43), chiefly segregating in an autosomal dominant inheritance mode. There was no functional data to support the pathogenicity of putative causative variants. This review showed that WS2 is the most common in Africa. Variants in PAX3 and SOX10 were the predominant genetic causes. This study emphasizes the need to further investigate in-depth clinical characterization, molecular landscape, and the pathobiology of WS in Africa.