Browsing by Author "Mall, Sumaya"

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    Factors associated with vector control for onchocerciasis control in sub-Saharan Africa (2000 – 2023) : a systematic review
    (University of the Witwatersrand, Johannesburg, 2024) Ngbede, Daniel; Kagura, Juliana; Mall, Sumaya
    Background: Onchocerciasis is a neglected tropical disease and the second most common infectious cause of blindness worldwide, after trachoma. The vector which carries this parasite is a blackfly from the simulium genus, the parasite is transmitted to humans through the bite of an infected black fly during a blood meal. Alternative control strategies such as local vector control have been employed to complement the mass administration of ivermectin. There remains no synthesis of studies that have examined the use of vector control for onchocerciasis in the Sub- Saharan African (SSA) region. Objective: To examine the factors associated with vector control in the fight against onchocerciasis in Sub-Saharan Africa as through synthesis of the literature. Methods: A systematic search was conducted of the Cochrane Library, PubMed, Web of Science, and Scopus databases to identify relevant studies. Studies had to be published in peer-reviewed journals between January 2000 and March 2023. Data were extracted from the studies. Two independent reviewers conducted quality assessments using the Joanna Briggs Institute (JBI) critical appraisal checklist. Results: Our search identified 343 studies of which 19 were included in this review. Several factors were found to influence blackfly vector control programs. Programmatic factors include intervention duration and effectiveness, implementation challenges, resource availability, and larvicide application practices. Vector-related factors include blackfly susceptibility to larvicides, species variation, and genetic mechanisms of resistance. Environmental factors such as rainfall patterns, river size, and the presence of dams affect blackfly breeding sites. Human-related factors encompassed community knowledge and engagement, commitment to sustainability, and human activities that impacted breeding habitats. Overall, the quality of the included studies was found to be high as per the quality appraisal tool. Conclusion: This systematic review emphasizes the importance of considering multiple factors in the design and implementation of effective blackfly vector control programs for onchocerciasis in sub-Saharan Africa. Programmatic challenges, vector biology, environmental factors, and human factors should be considered. Policymakers and public health practitioners should optimize interventions based on these findings
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    The relationship between childhood adversity, recent stressors, and depression in college students attending a South African university
    (BMC, 2018-03) Mall, Sumaya; Mortier, Philippe; Taljaard, Lian; Roos, Janine; Stein, Dan J. Stein; Lochner, Christine
    Background: College students are at risk of depression. This risk may be increased by the experience of childhood adversity and/or recent stressors. This study examined the association between reported experiences of childhood adversity, recent stressors and depression during the last 12 months in a cohort of South African university students. Methods: Six hundred and eighty-six first year students at Stellenbosch University in South Africa completed a health focused e-survey that included items on childhood adversity, recent stressors and mood. Individual and population attributable risk proportions (PARP) between experiences of childhood adversity and 12-month stressful experiences and 12-month depression were estimated using multivariate binomial logistic regression analysis. Results: About one in six students reported depression during the last 12 months. Being a victim of bullying and emotional abuse or emotional neglect during childhood were the strongest predictors of depression in the past year at both individual and population level. With regard to recent stressors, a romantic partner being unfaithful, serious ongoing arguments or break-ups with some other close friend or family member and a sexual or gender identity crisis were the strongest predictors of depression. The predictor effect of recent stressors was significantly reduced in the final model that adjusted for the type and number of childhood traumatic experiences. At a population level, academic stress, serious ongoing arguments or break-ups with a close friend or family member, and serious betrayal by someone close were the variables that yielded the highest PARP. Conclusions: Our findings suggest a significant relationship between early adversity, recent stressors, and depression here and throughout, consistent with the broader literature on predictors of depression. This study contributes to the limited data on college students’ mental health in low and middle income countries including on the African continent. The findings provide information on the population level effect sizes of trauma as a risk factor for depression, as well as on the relationship between specific recent stressors and depression in college students.
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    The relationship between the combined effects of life-course trauma and HIV on cognition in rural South African adults: A secondary data analysis
    (University of the Witwatersrand, Johannesburg, 2024) Kupa, Nkgodi Obed; Matsena-zingoni, Zvifadzo; Mall, Sumaya
    Background: Lifecourse traumatic events (TE) refers to both childhood and adult trauma. Childhood TE refers to a spectrum and domains of adverse experiences occurring before the age of 18. Global and South African-based research suggests that life-course TE are associated with both physical and mental disorders including HIV and poor cognition (also referred to as neurocognitive impairment (NCI)). While data suggests that life-course TE, HIV and NCI are highly prevalent in South Africa and risk of NCI has been researched, little is known of the combined effect of life-course TE and HIV on NCI in adulthood. To fill the gap in the literature, I analysed data from the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), from rural Bushbuckridge (Mpumalanga province). Study Aim To examine the combined (interaction) effect of TE and HIV infection on the cognition of older adults in South Africa. Methods: I analysed (secondary) data from the HAALSI study. The main exposures analysed were: life-course TE and HIV-positive status. A pre-analysis phase consisted of several exploratory steps to define the exposure and outcome: First TE data which had been measured by the English Longitudinal Study of Aging (ELSA) life history questionnaire were examined. The main exposure variable was coded 1 if one experiences a TE and 0 otherwise from seven potential TE. NCI, the main outcome variable was defined based on measuring cognitive domains: orientation and memory. A score≥1.5 standard deviations (SD) below the mean of the baseline cognitive function distribution on the cognitive assessment (managing to know the date, day, month and president) will mean no NCI while a score below the means some degree of NCI). The main outcome variable was cognition measured by the Oxford Cognitive Screener (OCS-plus). Based on the validation of Tablet-Based OCS-plus in HAALSI, OCS-Plus included nine brief tests measuring cognitive ability in nine different domains, including language, memory (intentional and incidental), and executive functioning (task switching-alternating jobs between tasks), attention (auditory), and praxis (doing things). A stand-alone application called OCS- Plus was developed using Matlab and Psychophysics Toolbox for Windows Surface Pro tablets. Further preparatory steps for the analysis included: the exposure variables (HIV status and composite trauma-defined as the presence of at least one trauma item-) were created as follows: 1. HIV status was categorized into HIV positive and negative and coded 1 and 0 respectively. 2. Composite trauma was coded 1 if ever experienced any of the seven trauma items and 0 if none were experienced. Four groups of participants were created by exposure status. These were: 1. HIV positive and also experienced TE. 2. HIV negative but experienced TE. 3. HIV positive but TE negative. 4. HIV negative and trauma negative. Descriptive statistics were calculated for both exposures and outcomes as well as relevant sociodemographic variables. Both unadjusted and adjusted logistic regression techniques were employed to examine the combined effect of life course TE and HIV on NCI in older adults. The adjusted logistic regression models were done: 1) handling HIV and composite trauma separately and 2) considering the interaction term of HIV and composite trauma. Variables such as education, employment status, age, nationality, gender, hypertension, stroke, HIV status, marital status and composite trauma were considered confounders and adjusted accordingly. Results: Of the 5,059 study participants recruited and residing in the Agincourt study area in Bushbuckridge, 65% of the study participants had experienced at least 1 TE, and the most common trauma experienced were “ever experiencing severe financial hardship which was experienced by 58.74% of the participants, 39.73% whom “ever experienced a natural disaster” and 23.30% “ever experienced a death of a relative or friend” and the prevalence of NCI was 7% ( n=352).. The median age of participants was 64 (IQR: 55-74) years; 53.07% of the study participants were females; 44.42% had no formal education, and 72.63% of the study participants were not working. In the multiple logistic regression model with the interaction term, the odds of having NCI decreased by 64% (AOR=0.36; 95%CI: 0.25-0.52) and 59% (AOR=0.41; 95%CI: 0.24-0.75) among those who had some primary school (1-7 years) and some secondary school (8+ years), respectively compared to those with no education. The odds of having NCI decreased by 98% (AOR=1.98; 95%CI: 1.05-3.72) among those who were not working compared to those employed. A one-year increase in age was associated with a 5% increase in the odds of having a cognitive impairment (OR=1.05; 95%CI: 1.04-1.07). Those who were married had 37% (OR=0.63, 95%CI: 0.47-0.84) reduced odds of having NCI compared to those who were married. Those without composite trauma had 90% (AOR=0.10; 95%CI: 0.07-0.15) reduced odds of having NCI compared to those who have composite trauma. Those who were HIV positive and had experienced composite trauma had an increased odds of 1.78 (95% CI: 1.04-3.04) of having NCI compared to those who are HIV negative and had not experienced composite trauma. In the interaction model, we found no association between HIV status, stroke, or hypertension and NCI. However, the results of the interactionmodel suggested a significant association between HIV and the composite trauma score on NCI. Conclusions: The results suggest that lifecourse TE and HIV infection influence NCI. The full HAALSI cohort could be employed to examine the effect of TE data collected at baseline and incident NCI at later waves
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    The relationship between traumatic events and quality of sleep in older adults in rural South Africa
    (University of the Witwatersrand, Johannesburg, 2024) Dzimbanhete, Tsitsi Cherry; Mall, Sumaya; Redman, Kirsten N.
    Introduction: A number of factors are associated with the quality of sleep, a broad measure that includes sleep duration and disturbance. There are many factors associated with quality of sleep including communicable and non-communicable diseases and life course traumatic events (TE). Older adults who have experienced life course TE and the onset of comorbidities may be at risk of fluctuations in their quality of sleep. However, there are limited data on the African continent examining these relationships. Therefore, this study aimed to bridge the aforementioned gap and 1. examine the prevalence of traumatic events (TE), 2. examined the prevalence of poor quality of sleep in adults in the Health and Aging in Africa: a longitudinal study (HAALSI) cohort 3. examine the relationship between the TEs and quality of sleep in the HAALSI cohort in the Mpumalanga Province of South Africa. Methods: A cross sectional analysis using data from the second of four waves of the HAALSI cohort was undertaken. The second wave which recruited 4176 participants was conducted between 2018 and 2019. Measures include the English Longitudinal Study of Aging life history data to estimate prevalence of TE, brief version of Pittsburgh Sleep Quality Index (B-PSQI) to estimate the prevalence of poor sleep quality and the relationship between TE and poor sleep quality. Descriptive analysis, bivariate and multivariate analysis of the data was conducted in Stata 17. Results: The mean age of the participants was 65 years (SD=13). The majority of the sample were of South African origin (70%). With regard to education status, less than half (43%) had not completed a formal education (i.e., primary school). Poor quality of sleep was reported by 27% of the participants. With regards to TEs 66% of the sample reported caregiving trauma, 58% accident and disaster TEs, 30% childhood trauma, 15% war related TEs and 22% community violence. The multivariate analysis suggested that participants with history of exposure to childhood TEs and war related TEs had higher risk of poor sleep quality (OR 1.5 (CI1.2-1.8)) and (OR 1.5(CI 1.2-2.0)) respectively. The other variables associated with higher risk of poor sleep quality were being married (OR=1.2 (CI 1.0-1.4)) history of smoking (OR=1.6 (CI 1.2-3.1)), mild to moderate (OR=1.7 (CI 1.3-2.1)) and major depression symptoms (OR=2.1 (CI 1.8- 2.7)), being obese (OR =1.3 (CI 1.0-1.6)) and being HIV negative (OR= 1.4 (1.0-1.6)). Conclusion: Exposure to war related and childhood TEs were found to be associated with poor sleep quality in the older adults in rural South Africa. While a cross-sectional analysis is valuable, an examination of the full cohort of the trauma at baseline and quality of sleep would inform trauma focused interventions that seek to improve quality of sleep in older adults