SA-MRC/Wits Agincourt Unit (Research Outputs/Publications)

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    There are no equal opportunity infectors: Epidemiological modelers must rethink our approach to inequality in infection risk
    (2022-02-09) Jon Zelner; Nina B Masters; Ramya Naraharisetti; Sanyu A Mojola; Merlin Chowkwanyun; Ryan Malosh
    Mathematical models have come to play a key role in global pandemic preparedness and outbreak response: helping to plan for disease burden, hospital capacity, and inform nonpharmaceutical interventions. Such models have played a pivotal role in the COVID-19 pandemic, with transmission models-and, by consequence, modelers-guiding global, national, and local responses to SARS-CoV-2. However, these models have largely not accounted for the social and structural factors, which lead to socioeconomic, racial, and geographic health disparities. In this piece, we raise and attempt to clarify several questions relating to this important gap in the research and practice of infectious disease modeling: Why do epidemiologic models of emerging infections typically ignore known structural drivers of disparate health outcomes? What have been the consequences of a framework focused primarily on aggregate outcomes on infection equity? What should be done to develop a more holistic approach to modeling-based decision-making during pandemics? In this review, we evaluate potential historical and political explanations for the exclusion of drivers of disparity in infectious disease models for emerging infections, which have often been characterized as "equal opportunity infectors" despite ample evidence to the contrary. We look to examples from other disease systems (HIV, STIs) and successes in including social inequity in models of acute infection transmission as a blueprint for how social connections, environmental, and structural factors can be integrated into a coherent, rigorous, and interpretable modeling framework. We conclude by outlining principles to guide modeling of emerging infections in ways that represent the causes of inequity in infection as central rather than peripheral mechanisms.
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    Interventions addressing the adolescent HIV continuum of care in South Africa: a systematic review and modified Delphi analysis
    (2022-04-29) Brian Zanoni; Moherndran Archary; Thobekile Sibaya; Tatiana Ramos; Geri Donenberg; Maryam Shahmanesh; Connie Celum; Audrey Pettifor; Linda Gail Bekker; Jessica Haberer
    Introduction: Compared with adults, adolescents in South Africa have larger gaps at each step of the HIV continuum of care resulting in low levels of viral suppression. Methods: We conducted a systematic review and modified Delphi analysis of interventions addressing the HIV continuum of care for adolescents in South Africa. We searched PubMed, Science Direct, and Google Scholar and online conference proceedings from the International AIDS Society, the International AIDS Conference, and the Conference on Retrovirology and Opportunistic Infections from 1 January 2010 to 30 September 2020. We then conducted a modified Delphi analysis with 29 researchers involved in the National Institutes of Health's Fogarty International-supported Adolescent HIV Implementation Science Alliance-South Africa to evaluate interventions for efficacy, feasibility and potential for scale-up. Results: We identified nine initial published articles containing interventions addressing the adolescent HIV continuum of care in South Africa, including five interventions focused on HIV diagnosis, two on antiretroviral therapy adherence and two on retention in care. No studies addressed linkage to care or transition from paediatric to adult care. Two studies discussed intervention costs. In-home and HIV self-testing, community-based adherence support, and provision of adolescent-friendly services were the most impactful and scalable interventions addressing the adolescent HIV continuum of care. Conclusion: Future interventions should work comprehensively across the adolescent HIV continuum of care and be tailored to the specific needs of adolescents.
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    The double-edged role of accessed status on health and well-being among middle- and older-age adults in rural South Africa: The HAALSI study
    (2022-09) Shao-Tzu Yu; Brian Houle; Lenore Manderson; Elyse A Jennings; Stephen M Tollman; Lisa F Berkman; Guy Harling
    Background: Social capital theory conceptualizes accessed status (the socioeconomic status of social contacts) as interpersonal resources that generate positive health returns, while social cost theory suggests that accessed status can harm health due to the sociopsychological costs of generating and maintaining these relationships. Evidence for both hypotheses has been observed in higher-income countries, but not in more resource-constrained settings. We therefore investigated whether the dual functions of accessed status on health may be patterned by its interaction with network structure and functions among an older population in rural South Africa. Method: We used baseline survey data from the HAALSI study ("Health and Aging in Africa: a Longitudinal Study of an INDEPTH Community in South Africa") among 4,379 adults aged 40 and older. We examined the direct effect of accessed status (measured as network members' literacy), as well as its interaction with network size and instrumental support, on life satisfaction and self-rated health. Results: In models without interactions, accessed status was positively associated with life satisfaction but not self-rated health. Higher accessed status was positively associated with both outcomes for those with fewer personal contacts. Interaction effects were further patterned by gender, being most health-protective for women with a smaller network and most health-damaging for men with a larger network. Conclusions: Supporting social capital theory, we find that having higher accessed status is associated with better health and well-being for older adults in a setting with limited formal support resources. However, the explanatory power of both theories appears to depending on other key factors, such as gender and network size, highlighting the importance of contextualizing theories in practice.
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    CD4+ T-cell count at antiretroviral therapy initiation in the "Treat AII" era in South A: an interrupted time series analysis.
    (2012-11-05) Yapa HM; Kim H-y; Post FA; Jiamsakul A; de Neve J-W; Tanser F; Iwuji C; Baisley K; Shamanesh M; Pillay D; Siedner MJ; Barnighausen T; Bot J
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    The socioeconomic gradient of alcohol use: an analysis of nationally representative survey data from 55 low-income and middle-income countries
    (2022-10-22) Yuanwei Xu; Pascal Geldsetzer; Jen Manne-Goehler; Michaela Theilmann; Maja-E Marcus; Zhaxybay Zhumadilov; Sarah Quesnel-Crooks; Omar Mwalim; Sahar Saeedi Moghaddam; Sogol Koolaji; Khem B Karki; Farshad Farzadfar; Narges Ebrahimi; Albertino Damasceno; Krishna K Aryal; Kokou Agoudavi; Rifat Atun; Till Bärnighausen; Justine Davies; Lindsay M Jaacks; Sebastian Vollmer; Charlotte Probst
    Background: Alcohol is a leading risk factor for over 200 conditions and an important contributor to socioeconomic health inequalities. However, little is known about the associations between individuals' socioeconomic circumstances and alcohol consumption, especially heavy episodic drinking (HED; ≥5 drinks on one occasion) in low-income or middle-income countries. We investigated the association between individual and household level socioeconomic status, and alcohol drinking habits in these settings. Methods: In this pooled analysis of individual-level data, we used available nationally representative surveys-mainly WHO Stepwise Approach to Surveillance surveys-conducted in 55 low-income and middle-income countries between 2005 and 2017 reporting on alcohol use. Surveys from participants aged 15 years or older were included. Logistic regression models controlling for age, country, and survey year stratified by sex and country income groups were used to investigate associations between two indicators of socioeconomic status (individual educational attainment and household wealth) and alcohol use (current drinking and HED amongst current drinkers). Findings: Surveys from 336 287 participants were included in the analysis. Among males, the highest prevalence of both current drinking and HED was found in lower-middle-income countries (L-MICs; current drinking 49·9% [95% CI 48·7-51·2] and HED 63·3% [61·0-65·7]). Among females, the prevalence of current drinking was highest in upper-middle-income countries (U-MIC; 29·5% [26·1-33·2]), and the prevalence of HED was highest in low-income countries (LICs; 36·8% [33·6-40·2]). Clear gradients in the prevalence of current drinking were observed across all country income groups, with a higher prevalence among participants with high socioeconomic status. However, in U-MICs, current drinkers with low socioeconomic status were more likely to engage in HED than participants with high socioeconomic status; the opposite was observed in LICs, and no association between socioeconomic status and HED was found in L-MICs. Interpretation: The findings call for urgent alcohol control policies and interventions in LICs and L-MICs to reduce harmful HED. Moreover, alcohol control policies need to be targeted at socially disadvantaged groups in U-MICs. Funding: Deutsche Forschungsgemeinschaft and the National Center for Advancing Translational Sciences of the US National Institutes of Health.
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    Evaluating the Validity and Reliability of the Gender Equitable Men’s Scale Using a Longitudinal Cohort of Adolescent Girls and Young Women in South Africa
    (2022-03) Paul D Wesson; Sheri A Lippman; Torsten B Neilands; Jennifer Ahern; Kathleen Kahn; Audrey Pettifor
    Inequitable gender norms and beliefs contribute to increased sexual risk behavior, and, among adolescent girls and young women (AGYW), risk of HIV acquisition. We investigated the longitudinal measurement properties of the Gender Equitable Men's Scale (GEMS) when applied to a cohort of AGYW in rural South Africa (2011-2015). We used item response theory [Person-Item maps, Differential Item Functioning (DIF)] and measurement invariance confirmatory factor analysis models to assess the validity and reliability of the GEMS instrument. Item difficulty and endorsement of gender equitable beliefs both shifted over time. DIF analysis identified item bias for over half of the items; influenced by age, pregnancy, sexual debut, and intimate partner violence. Measurement invariance models revealed strong longitudinal invariance properties. GEMS is a reliable longitudinal measurement of gender equitable beliefs, with notable bias for specific items when administered to subgroups. Additional items specific to the adolescent experience are warranted for a more stable assessment of gender equitable beliefs in a population facing shifting norms as they mature.
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    Health and economic benefits of secondary education in the context of poverty: Evidence from Burkina Faso
    (2022-07-06) Luisa K. Werner; Jan-Ole Ludwig; Ali Sie4; Cheik H. Bagagnan; Pascal Zabre; Alain Vandormael; Guy Harling; Jan-Walter De Neve; Gu¨nther Fink
    Even though formal education is considered a key determinant of individual well-being globally, enrollment in secondary schooling remains low in many low- and middle-income countries, suggesting that the perceived returns to such schooling may be low. We jointly estimate survival and monetary benefits of secondary schooling using detailed demographic and surveillance data from the Boucle du Mouhoun region, Burkina Faso, where national upper secondary schooling completion rates are among the lowest globally (<10%). We first explore surveillance data from the Nouna Health and Demographic Surveillance System from 1992 to 2016 to determine long-term differences in survival outcomes between secondary and higher and primary schooling using Cox proportional hazards models. To estimate average increases in asset holdings associated with secondary schooling, we use regionally representative data from the Burkina Faso Demographic Health Surveys (2003, 2010, 2014, 2017–18; N = 3,924). Survival was tracked for 14,892 individuals. Each year of schooling was associated with a mortality reduction of up to 16% (95% CI 0.75–0.94), implying an additional 1.9 years of life expectancy for men and 5.1 years for women for secondary schooling compared to individuals completing only primary school. Relative to individuals with primary education, individuals with secondary or higher education held 26% more assets (SE 0.02; CI 0.22–0.30). Economic returns for women were 3% points higher than male returns with 10% (SE 0.03; CI 0.04–0.16) vs. 7% (SE 0.02; CI 0.02–0.012) and in rural areas 20% points higher than in urban areas with 30% (SE 0.06; CI 0.19–0.41) vs. 4% (SE 0.01; CI 0.02–0.07). Our results suggest that secondary education is associated with substantial health and economic benefits in the study area and should therefore be considered by researchers, governments, and other major stakeholders to create for example school promotion programs.
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    Are cardiovascular health measures heritable across three generations of families in Soweto, South Africa? A cross-sectional analysis using the random family method
    (2022-09-23) Lisa J Ware; Innocent Maposa; Andrea Kolkenbeck-Ruh; Shane A Norris; Larske Soepnel; Simone Crouch; Juliana Kagura; Sanushka Naidoo; Wayne Smith; Justine Davies
    Objectives: Cardiovascular disease is increasing in many low and middle-income countries, including those in Africa. To inform strategies for the prevention of cardiovascular disease in South Africa, we sought to determine the broad heritability of phenotypic markers of cardiovascular risk across three generations. Design: A cross-sectional study conducted in a longitudinal family cohort. Setting: Research unit within a tertiary hospital in a historically disadvantaged, large urban township of South Africa. Participants: 195 individuals from 65 biological families with all three generations including third-generation children aged 4-10 years were recruited from the longest running intergenerational cohort study in Africa, the Birth to Twenty Plus cohort. All adults (grandparents and parents) were female while children were male or female. Primary and secondary outcome measures: The primary outcome was heritability of blood pressure (BP; brachial and central pressures). Secondary outcomes were heritability of arterial stiffness (pulse wave velocity), carotid intima media thickness (cIMT) and left ventricular mass indexed to body surface area (LVMI). Results: While no significant intergenerational relationships of BP or arterial stiffness were found, there were significant relationships in LVMI across all three generations (p<0.04), and in cIMT between grandparents and parents (p=0.0166). Heritability, the proportion of phenotypic trait variation attributable to genetics, was estimated from three common statistical methods and ranged from 23% to 44% for cIMT and from 21% to 39% for LVMI. Conclusions: Structural indicators of vascular health, which are strong markers of future clinical cardiovascular outcomes, transmit between generations within African families. Identification of these markers in parents may be useful to trigger assessments of preventable risk factors for cardiovascular disease in offspring.
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    Short-term local predictions of COVID-19 in the United Kingdom using dynamic supervised machine learning algorithms
    (2022-09-24) Xin Wang; Yijia Dong; William David Thompson; Harish Nair; You Li
    Background: Short-term prediction of COVID-19 epidemics is crucial to decision making. We aimed to develop supervised machine-learning algorithms on multiple digital metrics including symptom search trends, population mobility, and vaccination coverage to predict local-level COVID-19 growth rates in the UK. Methods: Using dynamic supervised machine-learning algorithms based on log-linear regression, we explored optimal models for 1-week, 2-week, and 3-week ahead prediction of COVID-19 growth rate at lower tier local authority level over time. Model performance was assessed by calculating mean squared error (MSE) of prospective prediction, and naïve model and fixed-predictors model were used as reference models. We assessed real-time model performance for eight five-weeks-apart checkpoints between 1st March and 14th November 2021. We developed an online application (COVIDPredLTLA) that visualised the real-time predictions for the present week, and the next one and two weeks. Results: Here we show that the median MSEs of the optimal models for 1-week, 2-week, and 3-week ahead prediction are 0.12 (IQR: 0.08-0.22), 0.29 (0.19-0.38), and 0.37 (0.25-0.47), respectively. Compared with naïve models, the optimal models maintain increased accuracy (reducing MSE by a range of 21-35%), including May-June 2021 when the delta variant spread across the UK. Compared with the fixed-predictors model, the advantage of dynamic models is observed after several iterations of update. Conclusions: With flexible data-driven predictors selection process, our dynamic modelling framework shows promises in predicting short-term changes in COVID-19 cases. The online application (COVIDPredLTLA) could assist decision-making for control measures and planning of healthcare capacity in future epidemic growths.
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    The relationship between depression symptoms and academic performance among first-year undergraduate students at a South African university: a cross-sectional study
    (2022-11-11) F Wagner; R G Wagner; U Kolanisi; L P Makuapane; M Masango; F X Gómez-Olivé
    Background: South African universities face a challenge of low throughput rates, with most students failing to complete their studies within the minimum regulatory time. Literature has begun to investigate the contribution of well-being, including mental health, with depression among students being one of the most common mental disorders explored. However, locally relevant research exploring associations between depression and academic performance has been limited. This research hypothesizes that the presence of depression symptoms, when controlling for key socio-demographic factors, has an adverse impact on student academic outcomes and contributes to the delay in the academic progression of students. Methods: The study used a cross-sectional design. Data were collected in 2019 from first-time, first-year undergraduate students using a self-administered online questionnaire. In total, 1,642 students completed the survey. The Patient Health Questionnaire-9 (PHQ-9) was used to screen for depression symptoms. Data on students' academic performance were obtained from institutional records. Bivariate and multivariate regression analyses were used to examine associations between depression symptoms and academic performance. Results: Most participants (76%) successfully progressed (meeting the requirements to proceed to the second year of university study). Of the participants, 10% displayed symptoms of severe depression. The likelihood of progression delay (not meeting the academic requirements to proceed to the second year of university study) increased with the severity of depression symptoms. Moderate depression symptoms nearly doubled the adjusted odds of progression delay (aOR = 1.98, 95% CI: 1.30-3.00, p = 0.001). The likelihood of progression delay was nearly tripled by moderate severe depression symptoms (aOR = 2.70, 95% CI:1.70-4.36, p < 0.001) and severe depression symptoms (aOR = 2.59, 95% CI:1.54-4.36, p < 0.001). The model controlled for field of study, financial aid support as well as sex and race. Conclusion: Higher levels of depression symptoms among first-year university students are associated with a greater likelihood of progression delay and may contribute to the low throughput rates currently seen in South African universities. It is important for students, universities and government departments to recognize student mental wellness needs and how these can be met.
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    Association between fetal abdominal growth trajectories, maternal metabolite signatures early in pregnancy, and childhood growth and adiposity: prospective observational multinational INTERBIO-21st fetal study
    (2022-08-20) Jose Villar; Roseline Ochieng; Robert B Gunier; Aris T Papageorghiou; Stephen Rauch; Rose McGready; Julia M Gauglitz; Fernando C Barros; Manu Vatish; Michelle Fernandes; Victor Zammit; Verena I Carrara; Shama Munim; Rachel Craik; Hellen C Barsosio; Maria Carvalho; James A Berkley; Leila I Cheikh Ismail; Shane A Norris; Chrystelle O O Tshivuila-Matala; Francois Nosten; Eric O Ohuma; Alan Stein; Ann Lambert; Adele Winsey; Ricardo Uauy; Brenda Eskenazi; Zulfiqar A Bhutta; Stephen H Kennedy
    Background: Obesity predominantly affects populations in high-income countries and those countries facing epidemiological transition. The risk of childhood obesity is increased among infants who had overweight or obesity at birth, but in low-resource settings one in five infants are born small for gestational age. We aimed to study the relationships between: (1) maternal metabolite signatures; (2) fetal abdominal growth; and (3) postnatal growth, adiposity, and neurodevelopment. Methods: In the prospective, multinational, observational INTERBIO-21st fetal study, conducted in maternity units in Pelotas (Brazil), Nairobi (Kenya), Karachi (Pakistan), Soweto (South Africa), Mae Sot (Thailand), and Oxford (UK), we enrolled women (≥18 years, with a BMI of less than 35 kg/m2, natural conception, and a singleton pregnancy) who initiated antenatal care before 14 weeks' gestation. Ultrasound scans were performed every 5±1 weeks until delivery to measure fetal growth and feto-placental blood flow, and we used finite mixture models to derive growth trajectories of abdominal circumference. The infants' health, growth, and development were monitored from birth to age 2 years. Early pregnancy maternal blood and umbilical cord venous blood samples were collected for untargeted metabolomic analysis. Findings: From Feb 8, 2012, to Nov 30, 2019, we enrolled 3598 pregnant women and followed up their infants to 2 years of age. We identified four ultrasound-derived trajectories of fetal abdominal circumference growth that accelerated or decelerated within a crucial 20-25 week gestational age window: faltering growth, early accelerating growth, late accelerating growth, and median growth tracking. These distinct phenotypes had matching feto-placental blood flow patterns throughout pregnancy, and different growth, adiposity, vision, and neurodevelopment outcomes in early childhood. There were 709 maternal metabolites with positive effect for the faltering growth phenotype and 54 for the early accelerating growth phenotype; 31 maternal metabolites had a negative effect for the faltering growth phenotype and 76 for the early accelerating growth phenotype. Metabolites associated with the faltering growth phenotype had statistically significant odds ratios close to 1·5 (ie, suggesting upregulation of metabolic pathways of impaired fetal growth). The metabolites had a reciprocal relationship with the early accelerating growth phenotype, with statistically significant odds ratios close to 0.6 (ie, suggesting downregulation of fetal growth acceleration). The maternal metabolite signatures included 5-hydroxy-eicosatetraenoic acid, and 11 phosphatidylcholines linked to oxylipin or saturated fatty acid sidechains. The fungicide, chlorothalonil, was highly abundant in the early accelerating growth phenotype group. Interpretation: Early pregnancy lipid biology associated with fetal abdominal growth trajectories is an indicator of patterns of growth, adiposity, vision, and neurodevelopment up to the age of 2 years. Our findings could contribute to the earlier identification of infants at risk of obesity.
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    Effects of early-life poverty on health and human capital in children and adolescents: analyses of national surveys and birth cohort studies in LMICs
    (2022-04-30) Cesar G Victora; Fernando P Hartwig; Luis P Vidaletti; Reynaldo Martorell; Clive Osmond; Linda M Richter; Aryeh D Stein; Aluisio J D Barros; Linda S Adair; Fernando C Barros; Santosh K Bhargava; Bernardo L Horta; Maria F Kroker-Lobos; Nanette R Lee; Ana Maria B Menezes; Joseph Murray; Shane A Norris; Harshpal S Sachdev; Alan Stein; Jithin S Varghese; Zulfiqar A Bhutta; Robert E Black
    The survival and nutrition of children and, to a lesser extent, adolescents have improved substantially in the past two decades. Improvements have been linked to the delivery of effective biomedical, behavioural, and environmental interventions; however, large disparities exist between and within countries. Using data from 95 national surveys in low-income and middle-income countries (LMICs), we analyse how strongly the health, nutrition, and cognitive development of children and adolescents are related to early-life poverty. Additionally, using data from six large, long-running birth cohorts in LMICs, we show how early-life poverty can have a lasting effect on health and human capital throughout the life course. We emphasise the importance of implementing multisectoral anti-poverty policies and programmes to complement specific health and nutrition interventions delivered at an individual level, particularly at a time when COVID-19 continues to disrupt economic, health, and educational gains achieved in the recent past.
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    Understanding the factors that impact effective uptake and maintenance of HIV care programs in South African primary health care clinics
    (2022-09-09) Alastair van Heerden; Xolani Ntinga; Sheri A Lippman; Hannah H Leslie; Wayne T Steward
    Background: There is an increasingly urgent gap in knowledge regarding the translation of effective HIV prevention and care programming into scaled clinical policy and practice. Challenges limiting the translation of efficacious programming into national policy include the paucity of proven efficacious programs that are reasonable for clinics to implement and the difficulty in moving a successful program from research trial to scaled programming. This study aims to bridge the divide between science and practice by exploring health care providers' views on what is needed to implement new HIV programs within existing HIV care. Methods: We conducted 20 in-depth interviews with clinic managers and clinic program implementing staff and five key informant interviews with district health managers overseeing programming in the uMgungundlovu District of KwaZulu-Natal Province, South Africa. Qualitative data were analyzed using a template approach. A priori themes were used to construct templates of relevance, including current care context for HIV and past predictors of successful implementation. Data were coded and analyzed by these templates. Results: Heath care providers identified three main factors that impact the integration of HIV programming into general clinical care: perceived benefits, resource availability, and clear communication. The perceived benefits of HIV programs hinged on the social validation of the program by early adopters. Wide program availability and improved convenience for providers and patients increased perceived benefit. Limited staffing capacity and a shortage of space were noted as resource constraints. Programs that specifically tackled these constraints through clinic decongestion were reported as being the most successful. Clear communication with all entities involved in clinic-based programs, some of which include external partners, was noted as central to maximizing program function and provider uptake. Conclusions: Amid the COVID-19 pandemic, new programs are continuously being developed for implementation at the primary health care level. A better understanding of the factors that facilitate and prevent programmatic success will improve public health outcomes. Implementation is likely to be most successful when programs capitalize on endorsements from early adopters, tackle resource constraints, and foster greater communication among partners responsible for implementation.
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    Reaching for the 'first 95': a cross-country analysis of HIV self-testing in nine countries in sub-Saharan Africa
    (2022-02) Eva van Empel; Rebecca A De Vlieg; Guy Harling; Maja E Marcus; Kathleen Kahn; Till W Bärnighausen; Livia Montana; Augustine T Choko; Jennifer Manne-Goehler
    Objectives: HIV self-testing (HIVST) offers a promising approach to increase HIV diagnosis and advance progress towards the UNAIDS 95-95-95 targets. We aimed to understand patterns of HIVST awareness and utilization in nine sub-Saharan African (SSA) countries, with the goal of identifying populations to target in disseminating this technology. Design: A cross-sectional study. Methods: We pooled individual-level population-based data from nine Demographic and Health Surveys (DHS) in SSA conducted 2015-2019 (Burundi, Cameroon, Guinea, Malawi, Senegal, Sierra Leone, South Africa, Zambia, Zimbabwe). Primary outcomes were HIVST awareness and utilization. We used logistic regression with survey fixed effects to explore the relationship between sociodemographic characteristics and these outcomes. Models were adjusted for sex, age, rural/urban residence, education, wealth, and marital status. We accounted for complex survey design. Results: The study sample included 177 572 people (66.0% women, mean age 29 ± 10 years), of whom 86.6% [95% confidence interval (95% CI) 86.4-86.7] were unaware of HIVST, 11.7% (95% CI 11.6-11.9) were aware of but never used HIVST, and 1.7% (95% CI 1.6-1.8) had used HIVST. In adjusted models, women were less likely to be aware of HIVST [odds ratio (OR) 0.75, 95% CI 0.71-0.79], but more likely to have used HIVST (OR 1.17, 95% CI 1.03-1.32) compared with men. Rural residents, those who were least educated, and poorest were less likely to have heard of or used HIVST. Conclusion: HIVST awareness and uptake were low. Rural, less educated, and lower income populations were least likely to have heard of or used HIVST. Efforts to scale-up HIVST in these settings should aim to reach these less advantaged groups.
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    Human respiratory syncytial virus diversity and epidemiology among patients hospitalized with severe respiratory illness in South Africa, 2012–2015
    (2015) Ziyaad Valley-Omar; Stefano Tempia; Orienka Hellferscee; Sibongile Walaza; Ebrahim Variava6; Halima Dawood; Kathleen Kahn; Meredith McMorrow; Marthi Pretorius; Senzo Mtshali; Ernest Mamorobela; Nicole Wolter; Marietjie Venter; Anne von Gottberg; Cheryl Cohen; Florette K. Treurnicht
    Background: We aimed to describe the prevalence of human respiratory syncytial virus (HRSV) and evaluate associations between HRSV subgroups and/or genotypes and epidemiologic characteristics and clinical outcomes in patients hospitalized with severe respiratory illness (SRI). Methods: Between January 2012 and December 2015, we enrolled patients of all ages admitted to two South African hospitals with SRI in prospective hospital-based syndromic surveillance. We collected respiratory specimens and clinical and epidemiological data. Unconditional random effect multivariable logistic regression was used to assess factors associated with HRSV infection. Results: HRSV was detected in 11.2% (772/6908) of enrolled patients of which 47.0% (363/772) were under the age of 6 months. There were no differences in clinical outcomes of HRSV subgroup A-infected patients compared with HRSV subgroup B-infected patients but among patients aged <5 years, children with HRSV subgroup A were more likely be coinfected with Streptococcus pneumoniae (23/208 11.0% vs. 2/90, 2.0%; adjusted odds ratio 5.7). No significant associations of HRSV A genotypes NA1 and ON1 with specific clinical outcomes were observed. Conclusions: While HRSV subgroup and genotype dominance shifted between seasons, we showed similar genotype diversity as noted worldwide. We found no association between clinical outcomes and HRSV subgroups or genotypes.
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    CHAT SA: Modification of a Public Engagement Tool for Priority Setting for a South African Rural Context
    (2022-02-01) Aviva Tugendhaft; Marion Danis; Nicola Christofides; Kathleen Kahn; Agnes Erzse; Marthe Gold; Rhian Twine; Audrey Khosa; Karen Hofman1
    Background: Globally, as countries move towards universal health coverage (UHC), public participation in decision making is particularly valuable to inform difficult decisions about priority setting and resource allocation. In South Africa (SA), which is moving towards UHC, public participation in decision-making is entrenched in policy documents yet practical applications are lacking. Engagement methods that are deliberative could be useful in ensuring the public participates in the priority setting process that is evidence-based, ethical, legitimate, sustainable and inclusive. Methods modified for the country context may be more relevant and effective. To prepare for such a deliberative process in SA, we aimed to modify a specific deliberative engagement tool - the CHAT (Choosing All Together) tool for use in a rural setting. Methods: Desktop review of published literature and policy documents, as well as 3 focus groups and modified Delphi method were conducted to identify health topics/issues and related interventions appropriate for a rural setting in SA. Our approach involved a high degree of community and policy-maker/expert participation. Qualitative data were analysed thematically. Cost information was drawn from various national sources and an existing actuarial model used in previous CHAT exercises was employed to create the board. Results: Based on the outcomes, 7 health topics/issues and related interventions specific for a rural context were identified and costed for inclusion. These include maternal, new-born and reproductive health; child health; woman and child abuse; HIV/AIDS and tuberculosis (TB); lifestyle diseases; access; and malaria. There were variations in priorities between the 3 stakeholder groups, with community-based groups emphasizing issues of access. Violence against women and children and malaria were considered important in the rural context. Conclusion: The CHAT SA board reflects health topics/issues specific for a rural setting in SA and demonstrates some of the context-specific coverage decisions that will need to be made. Methodologies that include participatory principles are useful for the modification of engagement tools like CHAT and can be applied in different country contexts in order to ensure these tools are relevant and acceptable. This could in turn impact the success of the implementation, ultimately ensuring more effective priority setting approaches.
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    Understanding Sex Differences in Childhood Undernutrition: A Narrative Review
    (2022-02-23) Susan Thurstans; Charles Opondo; Andrew Seal; Jonathan C. Wells; Tanya Khara; Carmel Dolan; André Briend; Mark Myatt; Michel Garenne; Andrew Mertens; Rebecca Sear; Marko Kerac
    : Complementing a recent systematic review and meta-analysis which showed that boys are more likely to be wasted, stunted, and underweight than girls, we conducted a narrative review to explore which early life mechanisms might underlie these sex differences. We addressed different themes, including maternal and newborn characteristics, immunology and endocrinology, evolutionary biology, care practices, and anthropometric indices to explore potential sources of sex differences in child undernutrition. Our review found that the evidence on why sex differences occur is limited but that a complex interaction of social, environmental, and genetic factors likely underlies these differences throughout the life cycle. Despite their bigger size at birth and during infancy, in conditions of food deprivation, boys experience more undernutrition from as early as the foetal period. Differences appear to be more pronounced in more severe presentations of undernutrition and in more socioeconomically deprived contexts. Boys are more vulnerable to infectious disease, and differing immune and endocrine systems appear to explain some of this disadvantage. Limited evidence also suggests that different sociological factors and care practices might exert influence and have the potential to exacerbate or reverse observed differences. Further research is needed to better understand sex differences in undernutrition and the implications of these for child outcomes and prevention and treatment programming.
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    Patterns of tobacco use in low and middle income countries by tobacco product and sociodemographic characteristics: nationally representative survey data from 82 countries
    (2022-07-01) Michaela Theilmann; Julia M Lemp; Volker Winkler; Jennifer Manne-Goehler; Maja E Marcus; Charlotte Probst; William A Lopez-Arboleda; Cara Ebert; Christian Bommer; Maya Mathur; Glennis Andall-Brereton; Silver K Bahendeka; Pascal Bovet; Farshad Farzadfar; Erfan Ghasemi; Mary T Mayige; Sahar Saeedi Moghaddam; Kibachio J Mwangi; Shohreh Naderimagham; Lela Sturua; Rifat Atun; Justine I Davies; Till Bärnighausen; Sebastian Vollmer; Pascal Geldsetzer
    Objectives To determine the prevalence and frequency of using any tobacco product and each of a detailed set of tobacco products, how tobacco use and frequency of use vary across countries, world regions, and World Bank country income groups, and the socioeconomic and demographic gradients of tobacco use and use frequency within countries. Design Secondary analysis of nationally representative, crosssectional, household survey data from 82 low and middle income countries collected between 1 January 2015 and 31 December 2020. Setting Population based survey data. Participants 1231068 individuals aged 15 years and older. Main outcome measures Self-reported current smoking, current daily smoking, current smokeless tobacco use, current daily smokeless tobacco use, pack years, and current use and use frequencies of each tobacco product. Products were any type of cigarette, manufactured cigarette, hand rolled cigarette, water pipe, cigar, oral snuff, nasal snuff, chewing tobacco, and betel nut (with and without tobacco). Results The smoking prevalence in the study sample was 16.5% (95% confidence interval 16.1% to 16.9%) and ranged from 1.1% (0.9% to 1.3%) in Ghana to 50.6% (45.2% to 56.1%) in Kiribati. The user prevalence of smokeless tobacco was 7.7% (7.5% to 8.0%) and prevalence was highest in Papua New Guinea (daily user prevalence of 65.4% (63.3% to 67.5%)). Although variation was wide between countries and by tobacco product, for many low and middle income countries, the highest prevalence and cigarette smoking frequency was reported in men, those with lower education, less household wealth, living in rural areas, and higher age. Co nclusions Both smoked and smokeless tobacco use and frequency of use vary widely across tobacco products in low and middle income countries. This study can inform the design and targeting of efforts to reduce tobacco use in low and middle income countries and serve as a benchmark for monitoring progress towards national and international goals.
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    Short- and long-read metagenomics of urban and rural South African gut microbiomes reveal a transitional composition and undescribed taxa
    (2022-02-22) Fiona B Tamburini; Dylan Maghini; Ovokeraye H Oduaran; Ryan Brewster; Michaella R Hulley; Venesa Sahibdeen; Shane A Norris; Stephen Tollman; Kathleen Kahn; Ryan G Wagner; Alisha N Wade; Floidy Wafawanaka; F Xavier Gómez-Olivé; Rhian Twine; Zané Lombard; H3Africa AWI-Gen Collaborative Centre; Scott Hazelhurst; Ami S Bhatt
    Human gut microbiome research focuses on populations living in high-income countries and to a lesser extent, non-urban agriculturalist and hunter-gatherer societies. The scarcity of research between these extremes limits our understanding of how the gut microbiota relates to health and disease in the majority of the world's population. Here, we evaluate gut microbiome composition in transitioning South African populations using short- and long-read sequencing. We analyze stool from adult females living in rural Bushbuckridge (n = 118) or urban Soweto (n = 51) and find that these microbiomes are taxonomically intermediate between those of individuals living in high-income countries and traditional communities. We demonstrate that reference collections are incomplete for characterizing microbiomes of individuals living outside high-income countries, yielding artificially low beta diversity measurements, and generate complete genomes of undescribed taxa, including Treponema, Lentisphaerae, and Succinatimonas. Our results suggest that the gut microbiome of South Africans does not conform to a simple "western-nonwestern" axis and contains undescribed microbial diversity.
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    Point-of-care ultrasound for tuberculosis management in Sub-Saharan Africa-a balanced SWOT analysis
    (2022-10) Véronique Suttels; Jacques Daniel Du Toit; Arnauld Attannon Fiogbé; Ablo Prudence Wachinou; Brice Guendehou; Frédéric Alovokpinhou; Péricles Toukoui; Aboudou Rassisou Hada; Fadyl Sefou; Prudence Vinasse; Ginette Makpemikpa; Diane Capo-Chichi; Elena Garcia; Thomas Brahier; Kristina Keitel; Khadidia Ouattara; Yacouba Cissoko; Seydina Alioune Beye; Pierre-André Mans; Gildas Agodokpessi; Noémie Boillat-Blanco; Mary Anne Hartley
    Point-of-care ultrasound (POCUS) is an increasingly accessible skill, allowing for the decentralization of its use to nonspecialist healthcare workers to guide routine clinical decision-making. The advent of ultrasound-on-a-chip has transformed the technology into a portable mobile health device. Because of its high sensitivity to detect small consolidations, pleural effusions, and subpleural nodules, POCUS has recently been proposed as a sputum-free likely triage tool for tuberculosis (TB). To make an objective assessment of the potential and limitations of POCUS in routine TB management, we present a Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis based on a review of the relevant literature and focusing on Sub-Saharan Africa (SSA). We identified numerous strengths and opportunities of POCUS for TB management, e.g., accessible, affordable, easy to use and maintain, expedited diagnosis, extrapulmonary TB detection, safer pleural/pericardial puncture, use in children/pregnant women/people living with HIV, targeted screening of TB contacts, monitoring TB sequelae, and creating artificial intelligence decision support. Weaknesses and external threats such as operator dependency, lack of visualization of central lung pathology, poor specificity, lack of impact assessments and data from SSA must be taken into consideration to ensure that the potential of the technology can be fully realized in research as in practice.