Research Publications (Health Sciences)
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Item Molecular surveillance of tuberculosis-causing mycobacteria in wastewater(Elsevier BV, 2022-02) Mtetwa, Hlengiwe N.; Amoah, Isaac Dennis; Kumari, Sheena; Bux, Faizal; Reddy, PoovendhreeThe surveillance of tuberculosis infections has largely depended on clinical diagnostics and hospitalization data. The advancement in molecular methods creates an opportunity for the adoption of alternative surveillance systems, such as wastewater-based epidemiology. This study presents the use of conventional and advanced polymerase chain reaction techniques (droplet digital PCR) to determine the occurrence and concentration of total mycobacteria and members of the Mycobacterium tuberculosis complex (MTBC) in treated and untreated wastewater. Wastewater samples were taken from three wastewater treatment plants (WWTPs) in the city of Durban, South Africa, known for a high burden of TB/MDR-TB due to HIV infections. All untreated wastewater samples contained total mycobacteria and MTBC at varying percentages per WWTP studied. Other members of the MTBC related to tuberculosis infection in animals, M. bovis and M. caprae were also detected. The highest median concentration detected in untreated wastewater was up to 4.9 (±0.2) Log10 copies/ml for total mycobacteria, 4.0 (±0.85) Log10 copies/ml for MTBC, 3.9 (±0.54) Log10 copies/ml for M. tuberculosis, 2.7 (±0.42) Log10 copies/ml for M. africanum, 4.0 (±0.29) Log10 copies/ml for M. bovis and 4.5 (±0.52) Log10 copies/ml for M. caprae. Lower concentrations were detected in the treated wastewater, with a statistically significant difference (P-value ≤ 0.05) in concentrations observed. The log reduction achieved for these bacteria in the respective WWTPs was not statistically different, indicating that the treatment configuration did not have an impact on their removal. The detection of M. africanum in wastewater from South Africa shows that it is possible that some of the TB infections in the community could be caused by this mycobacterium. This study, therefore, highlights the potential of wastewater-based epidemiology for monitoring tuberculosis infections.Item Wastewater-based surveillance of antibiotic resistance genes associated with tuberculosis treatment regimen in KwaZulu Natal, South Africa(MDPI AG, 2021-11) Mtetwa, Hlengiwe N.; Amoah, Isaac Dennis; Kumari, Sheena; Bux, Faizal; Reddy, PoovendhreeEssential components of public health include strengthening the surveillance of infectious diseases and developing early detection and prevention policies. This is particularly important for drug-resistant tuberculosis (DR-TB), which can be explored by using wastewater-based surveillance. This study aimed to use molecular techniques to determine the occurrence and concentration of antibiotic-resistance genes (ARGs) associated with tuberculosis (TB) resistance in untreated and treated wastewater. Raw/untreated and treated (post-chlorination) wastewater samples were taken from three wastewater treatment plants (WWTPs) in South Africa. The ARGs were selected to target drugs used for first- and second-line TB treatment. Both conventional polymerase chain reaction (PCR) and the more advanced droplet digital PCR (ddPCR) were evaluated as surveillance strategies to determine the distribution and concentration of the selected ARGs. The most abundant ARG in the untreated wastewater was the rrs gene, associated with resistance to the aminoglycosides, specifically streptomycin, with median concentration ranges of 4.69-5.19 log copies/mL. In contrast, pncA gene, associated with resistance to the TB drug pyrazinamide, was the least detected (1.59 to 2.27 log copies/mL). Resistance genes associated with bedaquiline was detected, which is a significant finding because this is a new drug introduced in South Africa for the treatment of multi-drug resistant TB. This study, therefore, establishes the potential of molecular surveillance of wastewater for monitoring antibiotic resistance to TB treatment in communities.Item Stakeholder knowledge and attitudes toward the use of predictive genetic testing in South Africa(Springer Science and Business Media LLC, 2022-12) Naidoo, Levani; Reddy, PoovendhreeThe use of predictive genetic testing, particularly for risk profiling in non-communicable diseases (NCDs), has the potential to benefit public health by decreasing the disease burden and alleviating the pressure on healthcare. It is thus important to assess knowledge and uptake among stakeholders. This study aimed to assess end users' (community, medical practitioners and medical students) knowledge and attitudes regarding the use and support of genomic medicine. A descriptive cross-sectional survey was conducted in Kwazulu-Natal (KZN) among 3 groups of stakeholders (n = 170): medical practitioners from both private and public healthcare, medical students from UKZN and community members represented by teachers. Three structured questionnaires using a Likert scale were administered. Responses were stratified by practice type, and a scoring scale was developed. Principal component analysis (PCA) was used to reduce data on all constructs that made up each variable. All three groups showed adequate knowledge and a positive attitude towards use, apart from medical students who were not as keen to support future use in their own practice. Although medical practitioners supported the use of this technology, with necessary guidelines, expertise and affordability, only 18% from private practice reported having used it. PCA reduced data to fewer parsimonious constructs for all 3 groups: common threads included an awareness that genetic testing may improve health and disease outcomes; guidelines for use; and the provision of education to increase awareness, training to bolster expertise and confidence to use these services. Participants in this study attributed a lack of uptake to limited expertise and professional support, and a lack of legislative guidelines. We recommend updating continuing professional development for medical practitioners and promoting community education concomitantly. Provision of guidelines and increased accessibility to resources are important.Item Teachers’ choices of teaching methods for environmental education : a case study of life skills teachers at a primary school in South Africa(African Journals Online (AJOL), 2021) Ruthanam, Melishnee; Reddy, Poovendhree; Pillay, DaisyThe success of environmental education has been attributed to several factors including teachers’ competencies and attitudes, teaching methodologies, availability of resources, and curriculum design. Many researchers in environmental education suggest that innovative and resourceful teaching approaches may translate into meaningful environmental education. This study provides an insight into the influence of this on environmental education in a South African classroom through a qualitative approach. Interviews were conducted to understand the teaching approaches used in the subject of Life Skills. The findings of the study suggest that the pedagogical content knowledge and identity of the teacher are determining factors for teachers’ pedagogical choices. This paper suggests that it is not the resources that are crucial to learning, rather the presence of a resourceful teacher. A resourceful teacher is able to introduce innovation regardless of the availability of teaching resources. This information could inform pre-service teacher training programmesin focusing on the development of a resourceful environmental education teacher. Keywords: environmental education, Life Skills, teaching approaches, Pedagogical Content Knowledge (PCK), educational resourcesItem Interaction between ambient pollutant exposure, CD14 (-159) polymorphism and respiratory outcomes among children in Kwazulu-Natal, Durban(Sage Publishing, 2016) Makamure, Michelle T.; Reddy, Poovendhree; Chuturgoon, Anil A.; Naidoo, Rajen N.; Mentz, Graciela; Batterman, Stuart; Robins, Thomas G.The objective of this study was to determine if the association between exposure to ambient air pollutants such as sulfur dioxide, nitrogen dioxde (NO2), nitrous oxide (NO), and PM10, and variation in lung function measures was modified by genotype. A validated questionnaire was administered to 71 African children to evaluate prevalence of respiratory symptoms. Atopy was evaluated by skin-prick testing and bihourly measures of lung function (spirometry) were collected. Gaseous air pollutant concentrations were monitored continuously. CD14 polymorphism was genotyped and plasma CD14 levels were measured. There was no statistically significant association between the CD14 (159) CTþTT polymorphism with any asthma-related phenotype. There was a significant association between lung function (forced expiratory volume in 1 second intraday variability) and NO2 and NO among participants carrying the CD14 CT/TT genotype for lags 1, 2, and the 5-day average. Similarly, statistically significant gene–pollutant interactions (p < 0.05) were found with NO and CD14 CT/TT at lag 2 and for the 5-day average. While there was no association with any respiratory phenotype (as determined by symptoms), the CD14 CT/TT genotype appeared to be protective to increased exposure to NO2 and NO.Item Prenatal exposures and DNA methylation in newborns: A pilot study in Durban, South Africa(Royal Society of Chemistry, 2016) Goodrich, Jaclyn M.; Reddy, Poovendhree; Naidoo, Rajen N.; Asharam, Kareshma; Batterman, Stuart; Dolinoy, Dana C.The in utero environment has the potential to influence epigenetic programming and subsequently the health of offspring. Even though pregnant women living in urban Africa are exposed to multiple chemicals and infectious agents that may impact their developing children, the neonatal epigenome has not been studied in these regions. We assessed whether prenatal exposures to air pollution and maternal human immunodeficiency virus (HIV) are associated with changes to DNA methylation throughout the epigenome using a pilot sample from the Mother and Child Environmental (MACE) birth cohort, of which 36% of the mothers are HIV positive. Families living in a high air pollution region (south Durban, n = 11) and a low air pollution region (north Durban, n = 11) with comparable socioeconomic characteristics were selected for analysis. DNA methylation was quantified in cord blood plasma DNA at >430 000 CpG sites using the Infinium HumanMethylation450 BeadChip. Sites associated with living in south Durban or maternal HIV infection (p < 0.001) were more likely to be hypomethylated and located in CpG islands. Top differentially methylated sites by region of Durban were enriched in pathways related to xenobiotic metabolism, oxygen and gas transport, and sensory perception of chemical stimuli when performing gene set enrichment testing with LRpath. Differentially methylated sites by maternal HIV status were enriched in cytochrome P450s, pathways involved in detection of chemical stimuli, metabolic processes, and viral regulation and processing. Given the small sample size of the study, future work examining the impact of prenatal exposures to air pollution, maternal infection, and antiviral treatment on the epigenome and downstream health implications is merited in Sub-Saharan African populations.Item Tumour necrosis factor α polymorphism (TNF-308α G/A) in association with asthma related phenotypes and air pollutants among children in KwaZulu-Natal(Thai Health Science Journals, 2016-09) Makamure, Michelle T.; Reddy, Poovendhree; Chuturgoon, Anil A.; Naidoo, Rajen N.; Mentz, Graciela; Batterman, Stuart; Robins, Thomas G.BACKGROUND: The study of gene-environment interactions enables us to further understand the pathogenesis of asthma and inflammation. The TNF-α gene has been associated with airway pathology in asthma but there is limited information in relation to pollutant exposure and the TNF-α 308G/A polymorphism. OBJECTIVE: To determine the risk conferred by the TNF-α 308(G/A) polymorphism on respiratory outcome and to evaluate whether the association between exposure to ambient air pollutants such as SO2, NO2, NO, and PM10 and variation in lung function measures is modified by genotype. METHODS: The sample comprised 129 African children (between 9-11 years old). A questionnaire based on guidelines from the British Medical Research Council and the American Thoracic Society was administered to all caregivers to evaluate the prevalence of respiratory symptoms. Atopy was evaluated by skin prick testing. Bihourly measures of lung function (spirometry) were collected at school five days per week over three week periods in each of four seasons (2004-2005) using digital hand-held devices. During each of the four intensive 3-week phases, gaseous air pollutant concentrations were monitored continuously. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-PFLP) analysis was used to detect the TNF-α 308 genotype and plasma TNF-α levels were measured using the human TNF-α Max Standard™ Enzyme-linked immuno-absorbent assay (ELISA) kit. RESULTS: The TNF-α variant A allele was common among this sample of African children (40% with an allelic frequency of 0.24). There was no significant association with the TNF-α G/A polymorphism and any respiratory linked phenotype, nor cytokine levels. However, when exposure to pollutants were analyzed with genotypic and phenotypic data, we found relatively modest interaction effects for the TNF-α 308 genotype. GEE models showed that children with the TNF-α 308 A allele had increased deterioration of lung function post pollution exposure to SO2 [β=2.62, CI:0.51-4.71, p=0.02 and pint=0.03] and NO [β=3.28, CI:0.68-5.89, p=0.01, pint=0.03]. CONCLUSION: The TNF-α 308 (G/A) polymorphism may be associated with increased pollutant-associated effects on FEV1 intraday variability for both SO2 and NO. The A allele may increase susceptibility to the adverse effects of air pollutants.Item The impact of hygiene and localised treatment on the quality of drinking water in Masaka, Rwanda(Taylor & Francis, 2013-12-17) Uwimpuhwe, Monique; Reddy, Poovendhree; Barratt, Graham James; Bux, FaizalThe worldwide prevalence of waterborne diseases has been attributed to the lack of safe water, inadequate sanitation and hygiene. This study evaluated socio-demographic factors, microbiological quality of water at source and point of use (POU) at households, water handling and sanitation practices in a rural Rwandan community. Thirty five water samples from the source, Nyabarongo River, and water at point of use (POU) treated with the Slow Sand Filter (SSF) and Sˆur’Eau methods, were analysed for total coliform and faecal coliform counts. Turbidity was measured in household samples. A structured questionnaire regarding water collection, storage, usage and waterborne disease awareness was administered to 324 women. Despite the significant reduction in coliforms and faecal coliforms from the Nyabarongo River following treatment using either SSF or Sˆur’Eau, the water at point of use was found to be unsafe for human consumption. The frequency of diarrheal diseases were significantly higher among people who did not wash hands before food preparation (P = 0.002) and after using a toilet (P = 0.007) than among those who did. There was a statistically significant association between education levels and water treatment practices at the households (P < 0.05). Participants had limited knowledge regarding water storage practices for prevention of household water contamination. A combination of treatment methods with appropriate water handling should be considered. In addition, education is a fundamental precursor to advocating water treatment at POU.Item Challenges of Directly Observed Treatment Strategy implementation in eThekwini Municipality, South Africa(AFAHPER-SD, 2014-06) Rajagopaul, Althea; Reddy, Poovendhree; Kistnasamy, Emilie JoyEThekwini Municipality in Kwazulu-Natal, South Africa has a high prevalence of Tuberculosis (TB) and reported a defaulter rate of 18.9% in 2007, in spite of the Directly Observed Treatment Short Course (DOTS) which was adopted in 1996. While numerous quantitative studies have evaluated aspects of the DOTS programme in South Africa, there are limited qualitative data on this issue. The aim of this study was to determine the challenges associated with the implementation of the DOTS programme in the eThekwini Municipality. Five participants, who were all involved in TB management and control within the municipality, were interviewed. Textual data were content analysed. Three themes relating to healthcare personnels’ reports on the challenges associated with implementing DOTS in the municipality emerged from the inductive analysis of transcripts namely; inadequate follow up and tracing of patients, training of health care personnel and choice of DOTS supporters and DOTS sites. In spite of the eThekwini Municipality’s commitment to TB control and management, problems with implementation of DOTS persist. Communication, reporting and co-ordination between the different levels of the TB programme are essential to optimise patient benefit from both the TB programme and community or home based care.Item Predictors of tuberculosis treatment defaulting in informal dwellers within the eThekwini Municipality, KwaZulu-Natal(FIDSSA, 2014) Rajagopaul, Althea; Reddy, Poovendhree; Kistnasamy, Emilie JoyGlobally, tuberculosis causes more than 2-million deaths annually. Despite the implementation of the directly observed treatment strategy (DOTS) in South Africa, cure and defaulter rates have not reached World Health Organization (WHO) target rates. This causes concern as it may increase the risks of the development of multiple drug-resistant tuberculosis. Prior to commencement of this study, the eThekwini Municipality reported a defaulter rate of 18.9% in 2007 and 29% in 2009, which is higher than the WHO guideline of 5%. In 2011, eThekwini reported a defaulter rate of 24.3%. Given these statistics and the impact that these high rates may have on susceptible populations and an already overburdened health system, this study aimed to investigate predictors of defaulting in informal dwellers of eThekwini Municipality, KwaZulu-Natal. The study population comprised 102 defaulters and 102 non-defaulters from informal settlements within eThekwini. It was a cross-sectional descriptive study. The Prince Cyril Zulu Communicable Disease Centre electronic tuberculosis register was used to trace defaulters who were interviewed from informal settlements. Demographic data for non-defaulters were matched from the Prince Cyril Zulu Communicable Disease Centre electronic tuberculosis register, but were not physically traced. A questionnaire was administered to all defaulters and retrospective data were obtained from the Prince Cyril Zulu Communicable Disease Centre register for non-defaulters. Multivariate logistic analysis found smoking, alcohol use and having a family member with tuberculosis to be statistically significant predictors of defaulting. Smoking [odds ratio (OR): 2.79, 95% confidence interval (CI): 1.15, 6.77, p-value ≤ 0.005], alcohol consumption (OR: 7.04, 95% CI: 2.96, 16.71, p-value ≤ 0.005), and having a family history of tuberculosis (OR: 4.60, 95% CI: 2.34, 9.04, p-value = 0.01), were all significantly associated with defaulting in informal dwellers. Smoking, alcohol use and having a family member with tuberculosis were predictors that informal dwellers would default from their treatment. These factors should be included in tuberculosis management programmes.