Electronic Theses and Dissertations (Masters)

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A visual analytics approach to characterising disease progression among adults with chronic diseases in rural Agincourt northeast South Africa
(University of the Witwatersrand, Johannesburg, 2024) Nhlapho, Mapule Dorcus; Kabudula, Chodziwadziwa
Chronic diseases pose a significant challenge to the healthcare systems in South Africa, calling for innovative approaches for comprehensive understanding and management. This research study utilizes the Agincourt HDSS-Clinic dataset to design and implement a visual analytics system using the R Shiny web application framework. Focused on adults with chronic diseases, the tool employs dynamic visualizations to show patterns of healthcare utilization and disease progression. Through the R Shiny platform, the system provides a user-friendly interface for exploring and interpreting complex data, offering valuable insights into patient healthcare behaviours and the dynamics of chronic illnesses. The study used data from a total of 26 426 patients consisting of 19 265 (73%) females and 7 161 (27%) males. The study revealed previously unrecognized associations between specific chronic conditions including the existence of a substantial intersection between HIV, Hypertension, and Diabetes with 101 patients experiencing the coexistence of all the three conditions. Notably, the visual analytics system facilitated the identification of distinct healthcare utilization patterns across different demographic groups highlighting the most frequently visited health facility accounted for 5 912 patient visits overall while the least visited health facility accounted for 1 447 patient visits. The findings underscore the effectiveness of visual analytics in uncovering trends within complex datasets. The implications of these findings extend beyond the immediate research scope, influencing healthcare strategies and contributing to the ongoing discussions on innovative solutions for chronic disease management. This study contributes to the evolving field of visual analytics in healthcare, demonstrating the potential for such tools to inform decision-making and enhance patient outcomes
Association between serum zinc level and dynamics of Group B Streptococcus colonisation among pregnant women in South Africa
(University of the Witwatersrand, Johannesburg, 2024) Dhar, Nisha; Madhi, Shabir A
Background Maternal colonisation by Group B Streptococcus (GBS) is a major risk factor for early onset invasive GBS disease among newborns. Zinc micronutrient plays a critical role in several biological processes that are essential to prevent bacterial colonisation and/or invasion. The aim of this study was to investigate the association of serum zinc levels with GBS rectovaginal new acquisition and clearance from 20 to 37+ weeks gestation in pregnant women. Methods Vaginal and rectal GBS colonisation was determined at 20–25 weeks (visit-1), followed by 3 subsequent visits at 5–6 weeks intervals, until 37–40 weeks gestation (visit-4). Serum was collected at visit-1 and visit-4 and serum zinc was estimated by inductively coupled plasma mass spectrometry. “New acquisition” group was defined as participants for whom GBS culture was negative at visit-1 and acquired GBS in one of the subsequent visits. Participants not colonised with GBS at any visits were categorized as GBS “persistently uncolonised”. Participants who remained colonised throughout all study visits were defined as “persistently colonised” group. GBS “clearance group” included participants who were colonised at enrolment (visit-1) and in whom GBS colonisation cleared by last visit (visit-4). Results Participants in persistently un-colonised group had significantly higher zinc geometric mean concentration (GMC) at visit-1 compared with those who had new acquisition (20.18 µmol/L; 95%CI 17.99-22.64 vs 13.68 µmol/L; 95%CI 12.59-14.87, p=0.03). Higher zinc concentration in the persistently un-colonised group when compared with new acquisition group was significantly associated with lower odds of GBS rectovaginal acquisition [Odds ratio (OR) 0.15, p=0.001]. The lowest zinc threshold significantly associated with 45% lower odds of new acquisition was ≥15 umol/L (27.2% in new acquisition vs 40.5% in persistently un-colonised; OR 0.55; 95%CI 0.31- 0.96; p=0.03). Furthermore, zinc concentration was higher among women in clearance group compared with those in persistently colonised group (20.03 µmol/L; 95%CI 16.54-24.27 vs 16.45 µmol/L; 95%CI 13.32-20.31, p=0.04). Conclusion There was an inverse association between serum zinc levels in pregnant women and odds of GBS acquisition in those not initially colonised. Zinc supplementation in early pregnancy could reduce risk of invasive GBS disease in their newborns
Breast cancer survival to 5 years among young (<40 years) women in the sub-saharan African breast cancer-disparities in outcome (ABC-DO) cohort study
(2024) Abioye, Oyepeju F.
Introduction: Breast cancer remains a key global health challenge, accounting for most prevalent cause of cancer-related deaths worldwide. The impact of age at diagnosis on breast cancer survival has not been extensively investigated within the African context. Therefore, this study’s objectives were to estimate the breast cancer survival time among women 40 years) women in the ABC-DO Cohort Study in SSA. Methods: Secondary data analysis of breast cancer patients from the multi-country ABC-DO Prospective Cohort Study of 5 African countries was carried out. Baseline characteristics of study participants were summarized using descriptive statistics. Kaplan Meier curves were generated to evaluate breast cancer survival time by age group “<40 years, 40-64 years, 65+ years”. With the aid of Cox Multivariate Regression Modelling, factors correlated with a 5-year survival differential between younger and older women were investigated and Hazard Ratios were calculated adjusting for confounders. Results: This study had a total number of 2158 participants, 462 (21.41%) were <40 years at diagnosis, 1314 were between 40-64years (60.89%), while 382 patients were 65 years and above (17.70%). A total of 1211 deaths were recorded at 5 years. The total time at risk and incidence rate at 5 years was 6086.73 person years and 33 per 100 women respectively. The lowest overall survival at 5 years was found among women <40 years (33.46%; CI = 0.28-0.38), followed by women aged 65 years+ (37.63%; CI = 0.32-0.42), and highest overall survival was among women in the 40-64 years age group (42.66%; CI=0.39-0.45). For each country, the 5-year probability of survival was higher among women aged 40-64 compared to women under 40. On Cox multivariate analysis, a 20% rise in mortality was reported among women < 40 years (aHR 1.20; 95% CI= 1.03- 1.36) compared to women between 40-64 years in the final model, at p<0.05. The variables significantly associated with 5-year survival differential between younger and older women were: HIV status, Residence, and Stage at Diagnosis. Conclusion: This study reports that breast cancer survival among women in sub-Saharan Africa is age-specific, with lower 5-year overall and country-specific survival among women < 40 years in comparison to older women. Factors associated with lower survival include stage at diagnosis, HIV status, and area of residence. Young women (<40 years) in SSA remain at risk of increased mortality from breast cancer, hence there is an urgent need for targeted strategies to achieve a more favorable stage at diagnosis and improved survival in this populace.
Cost utility analysis of long acting muscarinic antagonists (LAMAs) as an alternative to long acting beta agonists (labas) for treatment of severe COPD in the South African public sector
(2024) Thompson, Peggy
Objective- The study purposed to estimate the cost-effectiveness of Tiotropium, compared with Salmeterol and Indacaterol for chronic obstructive pulmonary disease (COPD) patients within the South African public sector. Methods- A global Markov model was adapted for the local setting and developed in Microsoft Excel. Transition probabilities and data on costs, resource use and effectiveness were obtained from literature. Outcomes were calculated for 3-years in the base case, then extrapolated over a 10-year and lifetime time horizon. A 5% discounting rate was applied according to local guidelines. Cost-effectiveness was estimated as the incremental cost per quality adjusted life year (QALY). One-way and probabilistic sensitivity analyses were conducted to consider model uncertainty. Results- When compared with Indacaterol (300µg), Tiotropium was dominant (less costly and more effective) across all time horizons. Conversely, Tiotropium was not cost-effective when compared with Indacaterol (150µg) and dominated by Salmeterol over the 3- and 10-year time horizons. The resulting ICURs exceeded the estimated willingness to pay thresholds for all scenarios. The deterministic sensitivity analysis revealed the new intervention cost and utility for mild COPD impacted most on intervention cost effectiveness. Conclusion- Tiotropium was deemed not cost-effective at the proposed price, when compared to usual care for COPD. A price reduction should be considered, to determine the feasibility of displacing existing maintenance therapies. Indacaterol 150µg appeared more cost-effective at the current price and effectiveness demonstrated.
Determinants of mortality in children younger than five years admitted with severe acute malnutrition to three hospitals in Vhembe district, Limpopo
(2024) Fakudze, Dakalo
Background: In 2014, one-third of child deaths occurring in South African hospitals were attributed to severe acute malnutrition. This study sought to determine demographic, family, socio-economic, clinical, and case-management factors contributing to mortality in severely malnourished children younger than 5 years admitted to three hospitals in Vhembe district, Limpopo, South Africa. Methods: A retrospective record review of children aged 6 to 59 months admitted with severe acute malnutrition over 30 months was conducted. Bivariable and multivariable regression analyses of determinants of mortality were undertaken. Results: Two hundred and forty-five children with severe acute malnutrition were identified. Their median (interquartile [IQR]) age was 14 (10, 18) months. The overall mortality was 26.9% (66/245). Determinants of mortality, based on the multivariable analysis, included diarrhoea on presentation (odds ratio [OR]=3.34, 95% CI 1.38, 8.10); anaemia (OR=3.30, 95% CI 1.28, 8.50]); a raised CRP (OR=9.29, 95% CI 2.81, 30.76]); and hyponatraemia (OR=6.64, 95% CI 2.70, 16.31). HIV status and a diagnosis of shock were not significant determinants of mortality. Conclusion: Severe acute malnutrition mortality was high, particularly for a high middle-income country setting. Factors that may be amenable to intervention include better management of the presenting illness, particularly diarrhea, a focus on electrolyte imbalance correction, and treatment of anemia.
Determinants of sub-optimal glycaemic control among patients enrolled in a medicine dispensing programme in Kwazulu-Natal: A cohort study, 2018 – 2021
(University of the Witwatersrand, Johannesburg, 2023) Johnston, Leigh Clare
Background: In South Africa, type 2 diabetes mellitus (T2DM) is a growing public health problem, thus, by 2030, 50% of T2DM patients, receiving treatment, must achieve optimal glycaemic control (haemoglobin A1c (HbA1c) ≤7%). The CCMDD (Central Chronic Medicines Dispensing and Distribution) programme allows glycaemically-stable patients to collect their medication from community-based pick-up points. While the CCMDD is a large public health programme, there is a paucity in stakeholder’s knowledge of T2DM patients glycaemic control over time. We determined glycaemic control for CCMDD-enrolled T2DM patients in eThekwini, South Africa from 2018-2021, as well as the rate and predictors of becoming sub-optimally controlled. Methods: We performed a cohort study, linking HbA1c data from the National Health Laboratory Service to CCMDD-enrolled patients in eThekwini, South Africa from 2018–2021. We included patients optimally controlled at their baseline HbA1c, and having ≥1 repeat test available. We used Kaplan Meier analysis to assess survival rates and Cox regression to determine associations between time to sub-optimal control (HbA1c > 7%) and several factors. Adjusted hazard ratios (aHR), 95% confidence interval (95% CI), and p-values are reported. Results: Of 41145 T2DM patients enrolled in the CCMDD, 7960 (19%) had an available HbA1c result over the study period. A quarter of patients (2147/7960; 27%) were optimally controlled at their baseline HbA1c. Of those controlled at baseline, 695 (32%) patients had a repeat test available, with 35% (242/695) changing their status to sub-optimal control. Patients prescribed dual-therapy had a higher risk of sub-optimal glycaemic control (aHR: 1.503; 95% CI: 1.16–1.95; p-value=0.002) compared to those on monotherapy. HbA1c testing frequency per national guidelines (aHR: 0.46; 95% CI: 0.24–0.91; p-value=0.024) was associated with a lower hazard of sub-optimal glycaemic control. Conclusions: HbA1c monitoring, in line with testing frequency guidelines, is needed to flag sub- optimally controlled patients who become ineligible for CCMDD enrolment. Patients receiving dual-therapy may require special consideration. Addressing these shortfalls can assist planning and implementation to achieve 2030 targets.
Early life factors associated with childhood trajectories of violence among the birth to twenty- plus cohort in Soweto, South Africa
(University of the Witwatersrand, Johannesburg, 2024) Muchai, Lilian Njeri; Kagura, Juliana; Naicker, Sara
Introduction Violence against children has devastating and long-term negative consequences on individuals' and society's health, social and economic well-being. There is limited research on the life course experience of violence especially in Africa. This study aimed to identify sub-groups of physical & sexual violence victimization patterns separately in childhood, and evaluate early life factors predicting these violence trajectories. Methods This study used data from age 5 to 18 years from the ongoing prospective Birth to Twenty Plus cohort (Bt20+). Children within the Bt20+ cohort with data on physical and sexual violence in at least 2-time points between 5 and 18 years were included in the analyses. Group-based trajectory modelling was employed to identify groups of children with similar patterns of violence over time. Descriptive statistics was used to summarize study variables by violence trajectory group membership, while multivariable logistic regression was used to identify early life factors measured between birth and 5 years, associated with violence trajectory group membership. Results Two trajectory groups were identified for both physical and sexual violence victimization. For physical violence victimization, the majority of participants fell into the adolescent limited group (65.1%) and just over a third (34.9%) of the children were in the chronic increasing group. For sexual violence victimization, most participants fell into the adolescent limited group (74.1%, with a quarter in the late increasing (25.9%) group. Early life factors associated with a higher risk of chronic increasing physical violence victimization trajectory group membership, after adjusting for covariates, were being male (aOR 1.67, 95% CI 1.31; 2.10) and having a mother with at least secondary education compared to higher education (aOR 1.73, 95% CI 1.08; 2.76). In addition, residing in middle, compared to low, socioeconomic households (aOR 0.68, 95% CI 0.50; 0.92) was protective against membership in this group. Residing in high compared to low socioeconomic households, was the only early life factor with marginally significant (aOR 0.63, 95% CI 0.42; 0.95) association with membership in the late-increasing sexual violence victimization trajectory group, with those in better-off households less likely to experience sexual violence victimization with this pattern. Conclusion Children within the same community can follow different patterns of both physical and sexual violence victimization across childhood. Identification of early factors that predict membership to sub-groups of violence trajectories provides key violence prevention intervention points that can preempt or mitigate children’s exposure or experience of violence. Future research should explore a larger variety of early life factors proximal to the child as well as those more distal at the community and school levels
Efficacy of water suppression method for controlling the emissions of submicron particles at a quarry, Boksburg, South Africa
(2024) Mkwanazi, D. D.
Background: Respiratory diseases has contributed 70% to worldwide occupational disease mortality in all industrial sectors since over a decade ago. Pneumoconioses occur as a result of accumulation of dust in the lungs. Silicosis, one of the most common forms of pneumoconioses, presents in three different forms namely acute, accelerated, and chronic silicosis. Quarrying and open cast mining are responsible for different workplace hazards including noise, trauma, vibration, ultraviolet radiation, and dust exposure, which may cause silicosis. Lung deposition of particulate matter depend on the particulate matter surface characteristics, aerodynamic size, and weight. Quarrying and stone crushing activities are associated with high levels of crystalline silica release. Water suppression has been proven to effectively control dust in mining and construction industries, but not enough attention has been paid on effects of water suppression on fine particulate matter. Purpose: To evaluate efficacy of water suppression as a dust control measure for submicron particles for the primary, secondary and tertiary treatment processes during the production of stone aggregates in a quarry. Methods: In this cross-sectional study data was collected using a Nanozen dust sampling device to monitor dust emissions in 0.300µm to 10.658µm bin sizes across 4 different sampling points namely primary, secondary, tertiary treatment area, and office complex at a quarry in Boksburg, South Africa. In the primary treatment area big rocks are crushed into 150mm smaller rock without dust suppression, the secondary area breaks them further into 57mm stones with water supperssion applied, and tertiary breaks them into 19mm and smaller stone products under further water suppression conditions. Primary treatment area and office complex were sampled as dry areas, while secondary and tertiary treatment areas were sampled as water suppression areas. Data was analysed based on mass and number concentrations for different bin sizes, and comparisons were made between dry and wet areas. The effect of water treatment (suppression) on submicron bin ranges (0.300-0.915µm) in terms of mass concentration and number concentration was analysed to determine its efficacy in reducing dust emissions in this range. Results: The total average mass concentration of 460.2 µg/m3 (±486.3) was emitted from the primary area without dust suppression with average of 2.22E+08 (±136958.7) number concentration. This was reduced to 6.02µg/m3 and 60.9 million (±552879) mass and number concentration respectively in secondary treatment area with water suppression. In tertiary area emissions were 10.52µg/m3 and 54.8 million particles/cm3 (±828126) respectively for mass and number concentrations following further water suppression, while in office area (no water suppression) 6.07µg/m3 and 44.4 million/cm3 mass and number concentrations were recorded respectively. Conclusions & Recommendations: Data showed reduction of emissions between primary and secondary area by 98.7% (mass concentration) and 72.5% (number concentration). Further treatment in tertiary treatment showed a further decrease in total average number concentration compared to secondary treatment. Emissions at the office block as a control site were consistent with emissions from secondary and tertiary treatment areas, demonstrating possible dispersion by wind. Water suppression was demonstrated to be effective against particle bin sizes larger than 1 micron, with progressively less effect on submicron particles as they became smaller. More research is recommended on suppression of submicron dust particulate matter emission and consideration of number concentration as a key dose matrix to determine exposure.
Evaluation of implementation fidelity to national guidelines on management of tuberculosis in paediatric patients in Homa-Bay County, Kenya
(2022) Kiptoon, Sharon Cherono
Background: Tuberculosis (TB) has been a major public health concern for a long time. Infection in children has not been given a lot of focus as in adults despite children being a vulnerable population with weaker immunity. Prognosis is worse when there is HIV/TB coinfection. The WHO rolled out guidelines for the management of TB in pediatric patients which were adopted by the Kenya Government. Health care workers then implement the guidelines. The Objectives of this study were to measure adherence to national guidelines on the management of Tuberculosis in Pediatric patients (up to 14 years) and to identify moderators affecting implementation fidelity. Methods: A convergent parallel mixed method design was used to collect information from TB treatment sites in Homa bay County. The study was conducted during the months of August, September and October 2018.Quantitative data collected focused on Pediatric patients between ages zero and 14. A checklist based on the guidelines was designed to review 442 records in the clinics for a four-year period (2014 to 2018). Qualitative data was collected through in-depth interviews with eight Sub-County TB coordinators. Interview moderators were based on Carrol et al Implementation Fidelity framework. Summation of "yes" and "No" responses were tallied to get an adherence score for the County as a whole and for the sub-counties individually. The qualitative analysis used the thematic method in excel spreadsheets. Results: Results showed high adherence for the County with a median of 80% (IQR 66.66-93.33%). Four of the sub-counties with normally distributed scored had a mean score of 79% and while the other four had a median score of 80% (66.66 – 93.33). Guidelines which had low implementation fidelity scores were those involving follow up tests i.e., sputum, gene X-pert and X-ray during duration of treatment. In the qualitative aspect good facilitation strategies were found to be in place from both the County and national TB programs. An attitude of fear, lack of knowledge on infection prevention, lack of skills to produce specimens for TB testing and staff shortages affected quality of treatment delivery. The health care workers reported ease in following the guidelines especially with the roll out of new guidelines which simplified diagnosis of TB in children, drugs which are dispersible and in fixed dose combination. Participant’s response to the intervention was poor with both health care workers and patients expressing difficulties with direct observed therapy schedule which required frequent visits and frequent follow up tests. Conclusion and recommendations: In conclusion, implementation fidelity to guidelines on management of tuberculosis is high. Good facilitation strategies is a positive moderator towards achieving high implementation fidelity. The national TB program in Kenya is doing well so far in monitoring the process of guideline implementation once rolled out, however, to be able to achieve the sustainable development goal eradicating TB, further follow up is needed in the facilities to improve the levels of adherence from 80% to 100%. Use of the conceptual framework by Carroll has proved to be a good guide in evaluating healthcare worker’s performance in implementing treatment guidelines It is recommended that health workers should undergo more sensitization on why certain guidelines have been put in place e.g., repeating sputum samples at different phases of treatment in order to improve quality of care. More training on vital procedures e.g., gastric aspirate should also be done to improve health workers' confidence and ease diagnosis of TB at younger age. Further research on implementation fidelity on other evidence based interventions would go a long way to improve service delivery and ensure other program goals are met.
Exposure and risk assessment of benzene, toluene, ethyl benzene and xylene (btex) in a petrochemical depot at Heidelberg, South Africa
(2022) Mdlalose, Richard John
Background: The International Labour Organization estimated 2.2 million workers are dying yearly from work-related accidents and occupational diseases, whilst about 270 million suffer serious injuries, and 160 million become ill due to their work. It is further estimated that work-related accidents and diseases cause 4% of annual Global Gross Domestic Product or US $1.25 trillion due to lost working time, workers’ compensation, the interruption of production, and medical expenses. In 2005, the ILO estimated that 440 000 people died throughout the world because of exposure to hazardous chemicals. In 2018 chemicals production was the second largest production sector in the world. Chemicals are indispensable and critical part of life. Their visible positive outcomes are quite palpable. They are well recognized for instance pesticides improve the quality of food production, pharmaceuticals cure illness, cleaning products help to establish hygienic living conditions. Chemicals are key development of final products that make life little easy for human beings, etc. Controlling employees ‘exposure to chemicals and preventing or minimizing emissions remains a significant challenge in workplaces throughout the world. The production, storage, and handling of petrochemical products particularly BTEX emissions are known and associated with potential harm to human and aquatic organisms. Some of the health effects associated with exposure to BTEX are the health effects on hematopoietic system, including pancytopenia. The benzene exposure leads to an acute myelogenous leukemia. The exposure to toluene, ethylbenzene, and xylene have been linked to the damaging the central nervous system and irritation of the respiratory system. Benzene and ethylbenzene are confirmed carcinogens (Benzene is classified as a Group 1 and ethylbenzene is a Group 2 B carcinogens). Purpose: To characterize, assess exposure and health risk assessment to benzene, toluene, ethylbenzene, and xylene (BTEX) at the petrochemical depot at Heidelberg in Gauteng, South Africa. Methods: Exposure sampling was done using a MiniRAE 3000 Photoionization detector (PID). The PID (equipment) was calibrated before the commencement of the monitoring program following the manufacturer’s operating manual. The PID equipment was used to collect the BTEX samples. The PID was mounted on a marked tripod stand at 1.5 m above ground and approximately 0.2 m to 0.5 m in the microenvironment (Exposure scenario) of the depot workers (Controllers and/or laboratory assistant) with the probe extended or placed within 30cm of the breathing zone of the depot workers. Sampling was conducted at three different exposure scenarios (workstations) i.e., density huts, laboratory, and during plant equipment cleaning in the plant (strainer removal) over three days period. The sampling started from 08h00 to 17h00. One workstation was sampled per day. The sampling of BTEX per workstation took 30 minutes per hour over ten hours, every hour BTEX was sampled for a duration of 30 minutes and in totality ten samples were collected per 12- hour shift, a total of 30 BTEX samples were collected over the 3 days period. Additionally, the measured BTEX concentrations were used to obtain dose estimates. Data from the equipment was exported to a Microsoft Excel spreadsheet. All outliners were removed from the data and a correction factor was applied to derive the final concentration. Thereafter, statistical tests using student F-test and Test were performed to evaluate for significant differences amongst paired comparisons. Results : The highest average BTEX concentrations were measured in the laboratory, followed by density huts and the least was measured during the removal of the strainer (plant equipment cleaning). The activity areas (exposure scenarios) served as direct sources for the BTEX vapours. The average benzene concentrations measured in three activity areas ranged from 469 ppm to 542 ppm. The highest benzene concentration was found to be 542 times higher than the current South African Occupational Exposure Limits of 1ppm. The average toluene concentrations measured ranged from 1335 pm to 1542 pm; the highest toluene concentration was found to be more than 30 times above the South African Occupational Exposure Limits of 50 ppm. The average ethylbenzene concentrations measured ranged from 433 ppm to 500 ppm; the highest concentration was found to be 5 times above the South African Occupational Exposure Limits of 100 ppm. The average xylene concentrations measured ranged from 1372 ppm to 1584 ppm, the highest concentration was found to be more than 15 times above the South African Occupational Exposure Limits of 100 ppm. All the measured BTEX compounds were found to be above their respective South African Occupational Exposure Limits. The cancer risk was determined to be 13 x 10-2 (male) and 10 x 10-2 (female), 14 x 10-2 (male) and 11x 10-2 (female), 16 x 10-2 (male) and 13 x 10-2 (female), 12 x 10-3 (male) and 10 x 10-3 (female) for the workers in the density huts, laboratory, strain remover (plant equipment cleaning), respectively. In all exposure scenarios (male and female) the cancer risk was found to be higher than the acceptable risk levels of 1E-4 . There were 13 males and 10 females in the population of 100 controllers who were likely to develop cancer when working density huts environment. In the laboratory work environment, 14 males and 11 females in a population of 100 controllers were likely to develop cancer, whereas 16 males and 13 female laboratory workers were likely to develop cancer in a population of 100 laboratory workers, and during plant equipment cleaning 12 males and 10 female controllers were likely to develop cancer in a population of 1000. Therefore, the potential of developing cancer was heightened by working in the laboratory and density huts. The risk of the number of employees who were likely to develop cancer was reduced when doing plant equipment cleaning. In all three activity areas, cancer risk for males was higher than for their female counterparts. This finding denotes that male were more vulnerable than females even though the exposure concentration is the same. The higher number of males who were likely to develop cancer in all the activity areas were influenced by two factors i.e., males have a shorter average life expectancy and higher average body weight versus their females’ counterparts. A hazard quotient was used to determine the non-carcinogenic health effects, a hazard quotient of greater than 1 was used as a reference value. A value greater than 1 denoted a higher possibility that depot workers will get health effects from exposure to the Toluene, ethylbenzene, and xylene (TEX). The hazard quotient for males ranged from 4.6 to 577.5, the highest hazard quotient was more than 577 times above the HQ reference value. The lowest was at density huts for xylene and the highest was at the laboratory for a chemist for xylene. The hazard quotient for females ranged from 3.15 to 399.00, the highest hazard quotient was more than 399 times above the HQ reference value. The lowest was at density for xylene and the highest was at the laboratory for laboratory assistant. From the results, both males and females had a hazard quotient far above 1 which means health effects arising from TEX exposure were anticipated. Conclusion: The results showed highest constant BTEX concentrations in the three exposure scenarios over the 12 hours shift. The BTEX emissions were generated by activities that were performed by the depot workers. Highest BTEX concentrations were measured at laboratory, followed by density huts and the least was measured during the removal of the strainer (plant equipment cleaning). The lack of effective vapour recovery system and natural ventilation in the laboratory and in density huts also contributed to the high BTEX concentrations measured in these areas. Individual BTEX component results measured in the three activity areas indicated concentrations that were far above the South African Occupational Exposure Limits for individual BTEX. The cancer risk score was found to be far above the reference USEPA cancer risk value and denoting that depot workers were likely to develop cancer. The hazard quotient for the three exposure scenarios was also found to be greater than the reference value of 1 which indicates the potential to develop non-carcinogenic health effects due to exposure in three exposure scenarios. Recommendations: The following recommendations are made to assist management of the depot to control employees’ exposure to BTEX emissions per activity area: Density huts: The practicality of introducing a vapour recovery system on workbenches to extract the VOCs generated during sample collection and from density measuring jugs should be investigated or alternatively, the introduction of an online fuels and density analysis should be investigated or the practicality of introducing sample bombs to collect fuel samples should be investigated. Keep the windows opened to promote an ingress of fresh air and allow BTEX emissions to escape. A practicality of introducing a controlled mechanical ventilation to blow vapours away from the breathing zone of the depot workers should be investigated. Laboratory: The practicality of automating or modifying the GC equipment in the laboratory to be able to conduct an online petrochemical analysis to control employees’ exposure should be investigated. The tasks that require rinsing of testing tubes with fuels, refilling of the testing tubes, and discarding of superfluous samples should be performed under controlled conditions, the practicality of introducing a vapour recovering system to control vapours emissions should be investigated. The current practice of keeping the decanting drum open should be discontinued to prevent the accumulation of vapours in the laboratory or alternatively, it should be kept under a vapour recovery system. The practicality of keeping the retained fuel samples under the vapour recovery system in the laboratory storage should also be investigated. The fume hood and two extraction units should be serviced on a regular basis. Cleaning of plant equipment (strainer removal): The practicality of automating the removal and lifting the strainer to be cleaned to increase the distance between the strainer and receptors (controllers) should be investigated. The practicality of putting the clogged-up strainer in degreaser bath to remove and clean the strainer with the view of automating the task to prevent employees ‘exposure to VOC emissions. Recommendations applicable to all activity areas: Employees exposed to BTEX including the other petrochemicals should undergo a risk-based medical surveillance program including biological monitoring to evaluate the efficacy of the existing controls and as part of a preventative medical surveillance program. Provide information, instruction, and training at regular interval about: - petrochemicals (BTEX) that employees are potentially exposed to at workplace and duties of persons who are likely to be exposed to VOCs vapour. The names and potential harmfulness of the BTEX at the workplace and the employees who are likely to be exposed. Significant findings of the BTEX exposure assessment (an occupational health risk assessment survey). Information on how to access the relevant safety data sheets and information that each part of an SDS provides. The work practices and procedures that must be followed for the use, handling, storage, transportation, spillage, and disposal of samples, in emergency situations, as well as for good housekeeping and personal hygiene. The necessity of personal exposure air sampling, biological monitoring, and medical surveillance; The need for engineering controls and how to use and maintain them. The need for personal protective equipment, including respiratory protective equipment, and its use and maintenance. The precautions that must be taken by an employee to protect themselves against health risks associated with exposure, including wearing and using protective clothing and respiratory protective equipment. The necessity, correct use equipment, maintenance and potential of safety facilities and engineering control measures provided. Supervisor/Line Manager must give written instructions of the procedures to be followed in the event of spillages, leakages, or any similar emergency situations to employees. Once the aforementioned information, instruction and training have been provided, enforce the wearing of the prescribed PPE including ABEK respirator and no employee should be allowed to enter and remain in respiratory zone without the prescribed PPE and respiratory protection equipment (ABEK respirator).
Facilitators and barriers influencing implementation of interventions to eliminate silicosis in the South African mining industry
(2024) Patrick, Chinyelu Josephine
Background Silicosis is an occupational disease that affects workers, their life, livelihoods, families and communities. Poor workers’ health and wellness impact negatively on company efficiency, productivity and profits leading to major economic losses to the whole society. Silicosis is an added burden to the health service in South Africa. The disease is caused by exposure to respirable crystalline silica (RCS) dust. In the South African mining industry, there is an increased risk of tuberculosis among mineworkers exposed to RCS dust and those who develop silicosis. Silicosis is incurable but preventable and RCS dust control is the key. Extensive efforts have been deployed globally and nationally toward the elimination of silicosis. In South Africa, the mining industry set milestones for RCS dust reduction and silicosis elimination by 2013, now extended to 2024. The National Programme for the Elimination of Silicosis in South Africa has only been partially successful due to poor implementation of interventions, the complexity of interventions, and non-compliance with enacted policies. This may account for the fact that novice, current and former mineworkers are still being diagnosed with silicosis in the country. This study aimed to describe the existing implementation strategies and explore the facilitators and barriers to implementation of silicosis elimination interventions in the mining industry, South Africa. Methods A cross-sectional exploratory qualitative study was conducted using in-depth interviews among 18 participants selected purposively based on knowledge and experience in the mining industry. The Consolidated Framework for Implementation Research (CFIR) guided the development of the interview guides, data collection and analysis. Framework analysis was conducted and the transcribed data were coded using a hybrid of inductive and deductive coding to derive themes and sub-themes. Results 18 participants consisting of representatives from DMRE, Minerals Council South Africa, MHSC, MOSH, mining companies, unions and an academic researcher were interviewed. The five main themes identified in this study were intervention-related factors, implementation related factors, human-related factors, health-related factors and contextual factors. The strategies identified in the study were found to be part of the facilitators for implementation. The facilitators identified in the study were technological advancement, communication and dissemination of strategies, the Minerals Council’s role, industry milestones, legislation, enforcement of regulations, monitoring and evaluation, and compensation benefits. The major barriers were the lack of implementation practices and inadequate enforcement. Conclusion In the study, CFIR framework was used to guide a systematic process that looked at the strengths and weaknesses of silicosis elimination in the larger mines under the leadership of the Minerals Council South Africa. A lot of work has been done in terms of communication, legislation, enforcement, provision of interventions and efforts from all stakeholders. There a is need to improve communication and feedback with mineworkers on the message of silica dust reduction, enforcement of legislation and policies.
Factors associated with burnout among healthcare workers in a rural context, South Africa: a cross-sectional study
(2024) Moses, Alexandra
Background. Healthcare providers (HCP) were at risk of burnout related to high levels of occupational stress in the workplace. However, there was little research in rural and primary care settings in subSaharan Africa. This study aimed to describe the individual and workplace factors of public sector HCP working in Mpumalanga province, their experience of burnout and to examine the factors associated with burnout.. Methods. A quantitative study design using a cross-sectional survey was employed. The research site was Nkomazi Local Municipality in Mpumalanga Province. All HCPs (n=1 139) working at the primary healthcare clinics, community health centres and district hospitals were invited to participate in the survey. Data were collected between April and September 2022 via a selfadministered, electronic questionnaire. A demographic and occupational questionnaire, the General Help Seeking Questionnaire and the Health and Safety Executive (HSE) indicator tool were used to assess individual and workplace factors. Burnout was assessed using the Maslach Burnout Inventory– Human Services Survey. Univariate and multivariate regression analyses were used to examine factors associated with burnout. Results. Just over a quarter (n=302; 26.5%) of HCP participated. Participants were aged between 23 and 61 years, mostly female (n=252; 83.44%) and nurses (n=235; 77.81%). Most participants (n=215; 71.19%) would seek help if they had an emotional problem, most likely from mental health professionals, and least likely from traditional healers. Increased work-related stress was present due to the demands and roles of HCP. High levels of burnout were observed for Emotional Exhaustion (Median score 26 (IQR: 18)) and Personal Accomplishment (median score 29 (IQR: 9)) but not for Depersonalisation (median score 7 (IQR: 9)). On univariate regression analysis, the individual factor of being married and the workplace factor of increased years of experience were statistically significant to all three subscales of burnout. HSE factors of demands, control, management support, peer support, relationships, role and change were highly statistically significant to Emotional Exhaustion, Depersonalisation and Personal Accomplishment. On multivariate regression analysis, no individual demographic, occupational or HSE factors were significantly associated with Emotional Exhaustion or Depersonalisation. Personal Accomplishment ii improved by 0.49 (95%CI: 0.10-0.89) for every one point increase towards improved work demands, by 0.84 (95%CI: 0.01-1.67) for every point score increase towards improved management support, and by 1.19 (95%CI: 0.48-1.90) for every point score increase towards having improved role. Conclusions. During 2022, HCPs working in a rural area in South Africa displayed high levels of burnout for Emotional Exhaustion and Personal Accomplishment but not for Depersonalisation. Improvements in work demands, managerial support and role were significantly associated with an increase in the experience of Personal Accomplishment. Further research is recommended to better understand the nuances of the work environment. Solutions should be explored and implemented to prevent burnout, with special consideration given to work demands, managerial support and role clarity as part of the effort to retain rural HCP in the public health system.
Factors associated with extreme nonadherence to tb treatment among adult defaulters attending Gqeberha clinic between 2018 and 2019
(University of the Witwatersrand, Johannesburg, 2024) Chipise, Elisha; Kagura, Juliana; Tshuma, Ndumiso
Background Tuberculosis remains a significant public health problem in sub-Saharan Africa leading to high morbidity, mortality, social and economic implications. Tuberculosis is a curable condition that can be eliminated. However, global efforts towards ending TB are under threat from patients’ nonadherence to effective TB treatment. This study aimed to determine the prevalence and factors associated with extreme nonadherence to TB treatment among adult defaulters attending Gqeberha clinic in South Africa. Methods The study is a secondary data analysis of a cross sectional study on TB defaulters attending Gqeberha clinic. The analysis included 144 participants with minimum age of 18 years who had defaulted treatment between April 2018 and September 2019. TB nonadherence and study characteristics were described using frequencies and percentages. Extreme nonadherence was defined by an aggregate score of at least 4 based on the Morisky Medication Adherence 8-item scale (MMA8). The prevalence of extreme nonadherence was estimated using percentage frequencies while univariable and multivariable logistic regression modelling were performed to identify the factors associated with extreme nonadherence. Results There were 18(12.9%) TB defaulters who had extreme nonadherence. The majority of TB defaulters 65.2% (n=90) were men. All participants involved had a minimum age of 18 years. 73.4% (n =102) of the study participants stayed in formal dwellings, 79.1% (n =110) were unemployed, 68.8% (n =95) had not attained matric level qualification and 78.4% (n =109) were either single, divorced or separated. A larger proportion of participants, 79.9% (n =111) stayed within 5km radius of Gqeberha clinic, 65.5% (n =91) experienced shorter waiting times and 84.2% (n =117) acknowledged constant availability of medicines at the health facility. However, 69.1% (n =96) did not have a family member who encouraged them to attend clinic visits, 64% (n =89) lacked adequate food whilst taking medication, and 80.6% (n=112) had inadequate income to cover their basic needs whilst on treatment. After adjusting for covariates, those who took other medication besides TB treatment had 0.33 times odds (95% CI: 0.11-0.97) of extreme nonadherence compared to their contrasting peers. All the other factors were not significant in the adjusted model. Conclusion The prevalence of extreme nonadherence to TB treatment among adult defaulters was low. The participants involved in the study were from low-income families with the majority being unemployed, having low educational attainment and lacking adequate food during treatment course. The use of multiple drugs was significantly associated with lower odds of extreme nonadherence. There is need to intensify programs aimed at improving adherence to treatment if the end TB by 2035 goal is to be realized.
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
Factors that promote and impede treatment adherence of out-patient mental health care users at a psychiatric hospital in Johannesburg
(University of the Witwatersrand, Johannesburg, 2024) Rowse, Savannah; Hlungwani, Tinstwalo Mercy
Background: Neuropsychiatric disorders are ranked third in the overall burden of disease in South Africa and are chronic disorders. Adherence (and nonadherence) to treatment for severe mental illness is a multifaceted phenomenon that influences and is influenced by multiple factors in one’s environment and context. However, due to the magnitude of this burden of disease and policy agendas promoting deinstitutionalization through community- based care, higher levels of services in South Africa are grappling with the revolving door phenomenon. Aim: To explore factors that promote and impede treatment adherence from the perspectives of mental health care users (MHCUs) in an outpatient department (OPD) Tara Hospital, Johannesburg in 2022/2023. Setting: Tara Hospital is a public specialized psychiatric hospital situated in Hurlingham, Johannesburg and is classified as tertiary and quaternary hospital due to the level of specialised services provided. MHCUs are referred from other tertiary hospitals in the Johannesburg metropolitan district or referred from the private sector for specialized services. Methods: An explorative, descriptive, and contextual qualitative research study was conducted over the 2022/2023 period at Tara Hospital’s OPD. Purposive convenience sampling was used to recruit 18 participants aged 18-65 and diagnosed with severe mental illness. In-depth interviews (IDIs) using a semi structured interview guide were conducted, transcribed, and then analysed using MAXQDA software. Results: A thematic analysis was used to highlight the five dominant themes and their sub themes that emerged from the research. The five dominant themes included: experience of mental illness and adherence, experience of Tara OPD, promoters of adherence, barriers to adherence and stigma. MHCU demonstrate rich insight into their experience of their mental illness, diagnosis, medication, and relapse. Tara OPD is protective factor and positive influence on adherence for its service users. MHCU’s engage dynamically with their adherence and use an array of practical strategies that support their adherence as well as emphasizing the positive influence of social and institutional support. The barriers to adherence included substance use, stigma, poor social support, poor routines, and coping strategies. This stresses the dynamic interplay and role of each level of the socio-ecological model. Conclusion: Adherence to treatment for severe mental illness does not occur in a vacuum of a MHCU simply taking their medication, but there are multiple factors and influences that are important to consider
Noise emissions and exposures among drill operators and assistants in an opencast mine in South Africa
(University of the Witwatersrand, Johannesburg, 2024) Zamisa, Thulile Senzekile; Nelson, G
Background: Noise is defined as ‘undesirable’ or unwanted sound and is one of the most common occupational hazards in the workplace. Millions of workers are exposed to workplace noise that is potentially damaging to hearing. Noise also creates psychological stress, interferes with communication, concentration and can reduce productivity. Objective: The objectives of this study were to compare noise exposures between drill operators and assistants, to compare the noise emitted by drilling machines with noise exposures, and to identify risk factors associated with noise exposure in these workers. Methods: A quantitative cross-sectional study was conducted at an opencast Platinum Group Metals (PGM) and chrome mine in South Africa. Personal noise measurements were recorded throughout the work shift, for 40 drill operators and 20 assistants, using a noise dosimeter. The noise emitted from 10 drilling machines was also measured, using a sound level meter. Information on age, years worked as a drilling operator/assistant, and specific drilling machines operated, was collected. Information about the drilling machines, such as the area where drilling was done, the type of drill and material being drilled, and machine hours was also collected. Noise exposures for drill assistants and drill operators were compared, using an independent two-sample Student t-test. The two-paired Student t-test was used to test for the differences between noise emissions and noise exposures for the drill operators and assistants. To identify risk factors associated with noise exposure, a multivariable linear regression model was used. The independent categorical variables were age, time in job, shift cycle, job title, machine hours, material drilled, machine type, and deployment area. The independent continuous variables were noise inside the machine cab, noise outside the machine cab window, and noise at 1 m from the drilling machine. The dependent variable wasnoise exposure for drill operators and assistants. Results: The majority (n=40, 67.7%) of the study participants were drill operators; there were 20 (33.3%) drill assistants. Most (n=14, 70.0%) of the drill assistants were 35 years or younger, while most of the drill operators (n=19, 47.5%) were 36 – 45 years of age. The drill assistants were exposed to significantly higher mean TWA noise levels than the drilling operators, viz. 92.0 and 81.7 dBA, respectively. All drill assistants (n = 20) and 32.5% (n = 13) of the drill operators were exposed to mean TWA noise levels ≥85 dBA. There were statistically significant differences between the drilling machine noise emissions (both inside and outside the drilling machine cab) and the noise levels to which both groups of workers were exposed. Noise exposure levels were significantly associated with job title, machine hours, noise emissions outside the cab window, and the deployment area. Conclusion: Drill assistants were exposed to higher noise levels than drilling operators. The integrity of the cab may reduce noise exposure for the drilling operators. The noise emissions measured outside the cab window of the drilling machine were higher than those inside the cab and 1 m from the drilling machine. This indicated the importance of ensuring that cabs are designed to ensure reduced noise exposure for the drill operators. Drill assistants need to understand that maintaining a distance away from the drilling machine is important to reduce noise exposure levels. Knowing what factors are associated with noise exposure allows the mine to implement control measures to reduce such exposures. Controlling noise at the source is important, and employing detection tools for noise, such as real time monitoring, is necessary to record accurate employee exposures to assess if controls are effective
Occupational noise exposure among groundskeepers at a public university in Gauteng, South Africa
(2024) Mokone, Moses
Background- There is sufficient scientific evidence indicating that excessive and prolonged exposure to noise causes noise-induced hearing loss (NIHL), also known as permanent hearing loss and other non-auditory effects such as sleep disturbance, hypertension, and interference with the nervous and cardiovascular systems. The World Health Organization (WHO) estimated that NIHL costs approximately 0.2% to 2% of the gross domestic product (GDP) of the developed nations in terms of compensation and economic burden on society. It also estimated that more than 16% of the NIHL in adults is attributable to occupational noise exposure. Although preventable, NIHL is one of the most widespread irreversible occupational disease worldwide and thus was declared as a serious occupational hazard. Worldwide, occupational noise exposure is widely regulated and most countries, including South Africa, use 85 dBA as the occupational exposure limit for noise exposure and has adopted the 3-dB exchange rate, with the exception of the US and Brazil, amongst others, which use the 5-dB exchange rate rule. Exchange Rate is the increase in noise level that corresponds to a doubling of the noise level. A few countries around the world such as the US, Japan and India use 90 dBA as a regulated limit for noise exposure. Acute hearing loss can also occur suddenly if a person is exposed to very high impact noise (above 140 dBC) for a short duration such as explosion and gun shots. Research shows that 8-hour average daily noise exposure levels between 75 dBA and 80 dBA are unlikely to cause hearing loss. The International Organization for Standardization (ISO 1999) “Acoustics - Determination of Occupational Noise Exposure and Estimation of Noise-Induced Hearing Impairment” provides damage risk criterion information that enable the prediction of NIHL at various audiometric frequencies and for varying exposure durations. Attempts to limit human exposure to noise are based on damage risk criterion. For example, the National Institute for Occupational Safety and Health (NIOSH) estimates a risk of NIHL after a 40-year working lifetime of 1% at 80 dBA, 8% at 85 dBA, and 25% at 90 dBA. This shows that the 85 dBA limit does not guarantee safety, since 85 dBA is already indication 8% excess risk. The WHO has indicated that workers employed in sectors such as manufacturing, transportation, construction, mining, utility, agriculture and military have the highest risk of 2 | P a g e NIHL. In the Services sector, which include Garden and Landscaping services, the extensive use of powered lawn maintenance machines results in widespread exposure to high levels of noise. The employees employed in the garden and landscaping sector such as groundskeepers, are in charge of maintaining general landscape of public and private areas such as sporting grounds, community parks and learning institutions grounds. Their main tasks involve a variety of outdoor activities such as clearing leaves, mowing lawns, cutting trees, trimming hedges, applying fertilizer, removing dead or unwanted plants and other general garden maintenance work. Noise exposure, which is one of the main health hazards that severely affect the health of these employees during operation of powered lawn maintenance machines such as leaf blowers, riding and push lawnmowers, brush-cutters and chainsaws can be a significant source of workplace noise exposure among groundskeepers. Although the literature on occupational noise exposure has concentrated on large industrial sectors (mining, construction, manufacturing and transportation), the problem extends to smaller operations such as lawn maintenance. Recent literature suggests that noise generating activities in small-scale operations, such as lawn maintenance, use high noise emitting machinery. Purpose- The purpose of this study was to evaluate occupational noise exposure levels of groundskeepers who operate different types of powered lawn maintenance machines at three campuses of a public university in Gauteng and estimate their risk of NIHL. Methods- A quantitative, cross-sectional study design conducted among groundskeepers following a nonprobability convenience sampling strategy was used. Personal and area noise exposure levels were evaluated in accordance with the South African National Standard (SANS) Code of Practice 10083:2013. The measurements for personal noise were conducted using a type 2 Casella dBbadges (personal noise dosimeters), which were placed on the groundskeepers’ shoulders, close to the ear adjudged as receiving the highest noise levels covering sufficient time representative of daily (task-based) exposure. Area noise measurements were performed using a type 1 Quest integrating sound level meter (SLM), which was mounted on a tripod stand and placed at approximately 1.5 meters above the floor and 1 m from the noise generating machine. In each measurement position, one-minute measurements were completed, and Aweighted equivalent noise levels (LAeq) were recorded. To ensure accuracy of measurements, the noise measuring instruments were calibrated before and after each series of measurements v using a calibrated portable acoustic calibrator as per the manufacturer’s instructions. The SLM and personal noise dosimeters (PNDs) were calibrated using a type 1 acoustic calibrator (Model QC-10, Quest Technologies, USA) and type 2 acoustic calibrator (Casella CEL 110/2, Regent House, Bedford, U.K) respectively. No significant shift in calibration was detected for any individual measurement. All the noise measuring instruments were externally calibrated by a South African National Accreditation System (SANAS) 17025 accredited laboratory. A questionnaire constructed by the primary researcher was utilized to record groundskeepers’ demographic information, work processes pertaining to tasks performed and noise exposure levels, including certain elements of hearing conservation practices such as information and training, audiometric testing, and use of hearing protective devices (HPDs). A total of 18 PND measurements and 17 area noise measurements were conducted at three university campuses i.e. Campus A, Campus B and Campus C. The noise measurements were conducted over a period of five (5) days (1-3 September 2021 and 3-4 November 2021). Data/ readings from the noise monitoring instruments were manually recorded on predesigned field sheets and manually entered onto Microsoft Excel spreadsheet. Thereafter, a statistical analysis using a one-way analysis of variance (ANOVA) was carried out to determine whether a significant difference existed between the mean personal and area noise exposure levels measured at three university campuses. Formulas from the SANS 10083 standard were used to calculate measured noise levels for comparison with the regulated noise rating limit of 85 dBA using Microsoft Excel spreadsheet Results- The results of this study showed that majority, 78% (14 out 18), of groundskeepers’ personal noise exposure levels (task-based) in the three campuses exceeded the legislated noise rating limit of 85 dBA, thus increasing groundskeepers’ risk to NIHL. Groundskeepers in campus A were exposed to the highest eight-hour equivalent continuous A-weighted sound pressure level (LAeq, 8h) with mean noise levels of 91.5 dBA ±4.7, followed by campus B and C with mean noise levels of 89.1 dBA ±4.0 and 86.9 dBA ±2.9 respectively. Peak noise exposure levels (LCpeak) measured as part of personal noise exposure in the three campuses ranged from 115.6 dB to 140.0 dB. These excessive peak noise exposures are attributed to the types of machines used during lawn maintenance activities. The overall statistical difference in the mean personal noise exposure levels (LAeq, 8h) and peak levels (LCpeak) between the three campuses were found to be not significant for both the LAeq, 8h (P = 0.304) and LCpeak (P = 0.607). vi Furthermore, majority, 71% (12 out 17), of area noise levels measured on specific lawn maintenance machines had equivalent continous A-weigted sound pressure level (LAeq) above the noise rating limit of 85 dBA. Machines measured in campus A had the highest area noise levels (LAeq) with mean noise levels of 98.8 dBA ±6.9, followed by campus B and C with mean noise levels of 92.9 dBA ±8.3 and 91.6 dBA ±5.1 respectively. The overall statistical difference in the mean area noise levels (LAeq) between the three campuses were found to be not significant (P = 0.135). The findings of this study demonstrated that the study participants comprised a total of 18 males across the 3 campuses, with mean working experience in the current job of five (5) years (ranging 2 – 11 years). Majority (9 out of 18 or 50%) of the participants were aged between 36–45, while only 16% (3 out of 18) were above the age of 56. The distribution of the participants according to their education was 100% secondary school. This may have positive implications for understanding of information and training material used for noise exposure awareness. The results of groundskeepers’ awareness to certain elements of hearing conservation program, with specific focus to information and training, audiometric testing, and use of hearing protection devices (HPDs) revealed that majority (95%) of groundskeepers were not trained about the noise rating limit and its meaning as required by Regulation 4 of the NIHL Regulations. Furthermore, it was found that, 50% of groundskeepers indicated that they never received information and training on the health effects of noise exposure while working at the university. In terms of audiometric testing, 78% of groundskeepers indicated that they were given audiometric testing while employed at the university. The study further indicated that majority (63%) of groundskeepers reported that, they use hearing protection devices (HPDs) while operating noisy machines. Notably, 90% of groundskeepers reported that, there is no one who is checking and supervising if they wore HPDs while operating lawn maintenance machines. The analysis further shows that, 47% of groundskeepers reported that, their HDPs were not comfortable when worn. Conclusion- The findings of this study have highlighted that, although the university had hearing conservation programs in place, there were shortcomings in the implementation of some elements of the program, in particular with regard to information and training, noise exposure monitoring and use of hearing protection devices. Most groundskeepers were exposed to noise vii levels exceeding the noise rating limit of 85 dBA and were at risk of acquiring NIHL. When considering the peak noise levels, the results of the study showed that there was only one groundskeeper from campus A who was exposed to noise levels exceeding the peak limit of 140 dBC. In all cases, employees should never be exposed to peak noise levels in excess of 140 dBC. Prevention, by reducing the noise exposure via engineering measures should be prioritized. The peak noise exposure limit of 140 dBC is regulated in the European Union Physical Agents (noise) Directive 2003/10/EC (2003) as an upper exposure action value. This EU noise directive is adopted by most European countries. Currently in the South African NIHL Regulations and SANS 10083 standard, peak noise exposure levels are not regulated. No significant differences were found in the mean area and personal noise levels measured in the three campuses. However, the use of certain machines such as backpack leaf blower and chainsaw were shown to be associated high noise exposure levels. Therefore, it is essential to ensure that noise levels on the lawn maintanance machines are significantly reduced by implementing good maintenance practices and buy quiet program. Information and training interventions should be aligned to target potentially exposed groundskeepers to modify their perceptions, noise control adherence approaches and continual motivation to sustain and improve an implemented hearing conservation program. This is the first study in South Africa to evalaute occupational noise exposure among groundskeepers in a public univeristy. Findings from this study may contribute to existing knowledge on occupational noise exposure among groundskeepers and may be investigated by other universities where lawn mainteance machines are used. However, the findings of this study may not be generalized to other universities because the study was only conducted in one university. Lessons drawn from this study are that there is a greater need to enhance hearing conservation measures in gardening and landscaping services within the universities.
Percentage positivity and determinants of cytomegalovirus infection and immunity in the public sector of south africa, 2007–2021: a time series analysis
(2024) Mhlabane, Nelisiwe Lynneth
Cytomegalovirus (CMV) infection is common in all age groups but is more prevalent in women of childbearing age and neonates. If left untreated, CMV can cause birth defects, recurrent infections, and death. Understanding the burden of CMV disease and its risk factors is important to instigate preventive measures. Despite global research conducted on CMV, there is still a paucity of studies conducted in South Africa that focus on CMV current infection and its determinants as well as immunity to CMV. The goal of this study was to determine the prevalence of CMV infection and immunity and the factors that influence them in South Africa’s public sector between 2007 and 2021. Methods: An analytical cross-sectional study was conducted using the results of CMV tests carried out on patient samples. The included test results were obtained from the National Health Laboratory Services and included results from all South African provinces from 2007 to 2021. The data were extracted from the National Health Laboratory Services Corporate Data Warehouse. Records of participants of all age groups whose data were available at the National Health Laboratory Services Corporate Data Warehouse were obtained. Patient demographic details and laboratory results were extracted into data collection tables. Data was cleaned and analysed using Stata 17. The CMV results considered in the analysis were serological (immunoglobulin M [IgM] and Immunoglobulin G [IgG] and molecular polymerase chain reaction tests carried out for routine CMV diagnosis. Immunoglobulin M, 2 polymerase chain reaction, and IgG seroconversion are markers of current CMV infection. A positive IgG antibody result is a marker of immunity (previous infection). A current CMV infection was defined as a positive CMV immunoglobulin M result, a CMV IgG seroconversion from negative to positive within three months of testing, or a positive CMV polymerase chain reaction result. Descriptive statistical analysis along with multivariable logistic regression analyses was used using age, sex, province, year and HIV. Results: A total of 432,170 records were analysed for CMV infection from 2007 to 2021. Among those with available CMV IgG test results, 97.84% (190,933/197,157) tested positive. For those with available CMV immunoglobulin M test results, 5.85% (16,850/288,267) tested positive. Overall, 4.40% (19,006/432,170) of records had evidence of a current CMV infection. Stratified analysis by sex showed similar proportions of current CMV infection for men (4.48%; 7,534/155,515) and women (4.08%; 10,649/261,310). Individuals aged 0–1 year had the highest proportion of current CMV infection at 7.35% (7,682/104,510), while those aged 2–15 years had the lowest proportion at 2.74% (979/35,686). Limpopo had the highest proportion of current CMV infections with 5.23%, (1,586/30,340), and the Western Cape had the lowest CMV current infection with 2.24% (788/35,114). In adjusted analysis, age and province were significantly associated with current CMV infection. Using individuals 0–1 year as the reference, all other age groups were less likely to test positive for CMV; the age group 2–15 years had the lowest CMV current infection (AOR = 0.34; 95% CI = 0.32–0.36). Limpopo (AOR = 1.91; 95%CI = 1.76–2.0; p = <0.0018) had the highest odds of current CMV infection while Western Cape had the lowest odds (AOR = 0.66; 95%CI = 0.60–0.73; p = <0.001). HIV infection, sex, and season were not associated with current CMV infection in the adjusted analysis. Regarding CMV immunity, the age group 26–35 years had the highest number of individuals who were IgG positive (99.18%; 45,845/46,223). The Northern Cape province had the highest concentration of IgG-positive individuals (98.81%; 407/4,460), and the year 2012 had the largest percentage of IgG-positive individuals (98.29%; 11,607/11,809). Conclusion: Age and place of residence (province) were associated with current CMV infection. Cytomegalovirus seroprevalence did not differ by gender. We found that a significant proportion of children are not susceptible to CMV infection. More recent 3 data would be useful to evaluate CMV infection in the South African populace and to give a clearer idea of the epidemiology of CMV infection. Meantime, without an effective CMV vaccine, the major preventive measure is educating people about CMV risk mitigation measures. Cytomegalovirus infection vaccines are still in the early phases of development, and our study contributes to identifying a potential target age for vaccination.
Predictors of frailty and multimorbidity in adults aged 40 to 65 years in a rural population cohort in Burkina Faso
(University of the Witwatersrand, Johannesburg, 2024) Georges, Some; Kandala, Ngianga-Bakwin
Background: Frailty and multimorbidity are vulnerable geriatric syndromes that pose a disability problem among the elderly in Sub-Saharan Africa (SSA). Assessment of factors associated with frailty and multimorbidity in middle-aged adults has remained limited despite the prevalence established in previous studies. We determined factors associated with frailty and multimorbidity among middle-aged adults in rural areas from 2015 to 2022 in Burkina Faso. Methods: This study utilized data from the Africa Wits-INDEPTH Partnership for Genomic Research (AWI-Gen) sub-study, a retrospective cohort study of 1500 participants aged 40-65 residing in Nanoro and Yako in Burkina Faso between 2015-2022. Each participant was asked to complete a standardized and structured questionnaire on socio-demographic, lifestyle, and clinical information. In addition, measures of Fried's phenotypic frailty components, and twelve chronic diseases were assessed for derivation into frailty and multimorbidity score variants respectively. To determine the risk factors associated with frailty and multimorbidity, we performed an ordinal and multinomial logistic regression analysis respectively with a significance level of 5%. Results: The prevalence of pre-frailty and frailty was 59.3% and 8.5% respectively while that of multimorbidity was 38.3%, where the multimorbidity prevalence rate stratified by existing chronic diseases was 13.0%. Half of the participants who had multimorbidity were frail (47.2%) while 10.4% of frail participants had multimorbidity. Weight loss (23.9%) and self-reported exhaustion (23.1%) were the most frequent phenotypic components. Dyslipidemia (63.9%), hypertension (26.4%) and rheumatic arthritis (15.0%) were the most frequent chronic diseases. On the one hand, age (≥50 years, aOR 1.4[1.0-1.9]), being widowed (aOR 1.5[1.1-2.1]), being unemployed (aOR 2.5[1.1-5.8]), smokeless tobacco use (aOR 2.5[1.1-5.7]), being underweight (aOR 26.2[17.1-40.2]) and multimorbidity (aOR 1.4[1.0-2.1]) were independently associated with increased odds of frailty. However, fruits (aOR 0.9[0.8-1.0]) and vegetables consumption (aOR 0.9[0.8-1.0]), and being highly active in weekly activities (aOR 0.1[0.0-0.2]) significantly reduced the odds of frailty. On the other hand, age (≥60 years, RRR 1.8[1.1-2.8]), being a woman (RRR 2.6[1.7-3.9]), being widowed (RRR 1.6[1.0-2.7]), being unemployed (RRR 4.5[1.1-18.0]), overweight (RRR 5.0[2.8- 9.1]), obesity (RRR 3.4[1.1-11.0]), pre-frailty (RRR 1.8[1.2-2.6]) and frailty (RRR 2.1[1.0-4.2]) were strongly associated with an increased risk of multimorbidity. Nevertheless, the consumption of alcohol (RRR 0.4[0.3-0.6]) and fruit (RRR 0.9[0.8-1.0]) significantly reduced the risk of multimorbidity. There was no significant association with determinants such as gender, level of education, smoking status. Conclusion: These findings provide additional evidence on the determinants of frailty and multimorbidity in Burkina Faso. Community awareness initiatives should be strengthened to influence lifestyle on tobacco consumption, alcoholism, physical activity, and vitamin supplementation associated with the consumption of fruits and vegetables
Prevalence of Group B Streptococcus colonization and serotype distribution among pregnant women in South Asian and African countries
(University of the Witwatersrand, Johannesburg, 2024) Kwatra, Gaurav; Madhi, Shabir A.
Background: Recto-vaginal Group B Streptococcus (GBS) colonization in pregnant women at the time of labour is the major risk-factor for developing invasive GBS disease within 7 days of age (early onset disease; EOD). We investigated prevalence of GBS recto-vaginal colonization at the time of labour among pregnant women and vertical transmission to their newborns across six African and two south-Asian countries. Methods: This multi-country prospective, observational cross-sectional study was undertaken in six African [(Ethiopia (Adama city), Kenya (Kilifi), Mozambique (Manhica), Nigeria (Gwagwalada), Mali (Bamako) and South Africa (Johannesburg) and two Southeast Asian countries (Bangladesh (Mirzapur) and India (Vellore)]. Inclusion criteria included pregnant women 18 to 45 years of age, delivery at ≥37 weeks gestation and documented to be HIV-uninfected prior to study-enrolment. Lower vaginal swabs, rectal swabs and urine were collected from the mothers and separate skin surface swabs of the umbilicus, outer ear and axillary fold; and rectal and throat swabs were obtained from the newborn for GBS culture. Standardized sampling and culture using direct plating and selective broth media for detection of GBS colonization in the mother-newborn dyads was undertaken across the sites. Serotyping of GBS isolates was done in South Africa. Results: Overall, 6,922 pregnant women were enrolled from January 10th , 2016 to December 11th , 2018. Of 6922 women who were enrolled, 6514 (94.1%; 759 to 892 per site) were included in the analysis. Overall, the prevalence of maternal GBS colonization was 24.1% (95%CI 23.1- 25.2; 1572/6514) being highest in Mali (41.1%, 95%CI: 37.7-44.6; 314/764) and lowest in Ethiopia (11.6%, 95%CI:9.5-14.1; 88/759). The overall rate of vertical transmission of GBS was 72.3% (95%CI 70.0-74.4; 1132/1566); being highest in Mozambique (79.2%, 95%CI 73.3-84.2); 168/212) and lowest in Bangladesh (55.8%, 95%CI 47.5-63.8; 77/138). The five most common GBS colonizing serotypes were Ia (37.3%; 586/1572), V (28.5%; 448/1572), III (25.1%; 394/1572), II (9.2%; 144/1572) and Ib (6.5%; 102/1572). There was geographic variability in serotype proportion distribution. Serotype VII was the third most common serotype in India (8.5%, n=15/176) and serotype VI was mainly identified in Bangladesh (5.8%) and India (5.7%). Conclusion: Our study reported high prevalence of GBS colonization in most settings, with some geographic variability even within African countries. Our findings suggests that there is likely to be a significant burden of EOD across the study sites. Post-licensure vaccine effectiveness studies should also focus on maternal GBS serotype distribution as non-vaccine serotype replacement could occur due to vaccine immune pressure

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