3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item The prevalence of talent tuberculosis infection and associated risk factors among young people in South Africa: a systematic review and meta-analysis(2018) Ngozi, Udeh JudithBackground: Latent tuberculosis infection (LTBI) is a condition whereby people harbour live Mycobacterium tuberculosis (M. tuberculosis) without any evidence of active tuberculosis (TB) infection. The World Health Organisation (WHO) agenda for eradicating TB revolves on screening and treating people with LTBI in high TB prevalent regions. Studies on LTBI claim that by the typical age of sexual debut, about 50% of the young people in South Africa harbour LTBI and roughly 75% by the age of 25 years. It is imperative to contribute to South Africa’s readiness towards WHO agenda for LTBI treatment. Using a Systematic Review and Meta-Analysis, we summed up study measures of effects on LTBI and made a conclusion on the purported prevalence and associated risk factors of LTBI among young people (0-19 years) in South Africa. Method and analysis: We used studies which estimated the prevalence and risk factors of LTBI among young people (0-19 years) in South Africa as diagnosed by Tuberculin skin test (TST) and InterFERON Gamma Release Assays (IGRAs). Studies were selected using predefined eligibility criteria and quality assessment tools to minimize bias. Random-effects model was used to weight the studies and Heterogeneities were determined using I-squared (I2) heterogeneity statistic. Effect measures were extracted at 95% confidence interval (CI) and the overall estimates pooled using Stata version 14 at 90% CI to accommodate minor variations in the selected studies. Result: Due to lack of data for all the Provinces, the results obtained in this review are for two Provinces (Western Cape and Gauteng) only. We found the pooled prevalence of LTBI among young people in the two Provinces to be 37% (90% CI: 34%, 41%) using TST and 40% (90% CI: 34%, 46%) using IGRAs. Pooled prevalence for Western Cape is 41% (90% CI: 37%, 44%) and Gauteng is 23% (90% CI: 19%, 26%). Conclusion: This Systematic review and meta-analysis did not establish the fact that the burden of LTBI among young people in South Africa is high as there were no studies in all the Provinces to back the claim. The available studies on the subject did not represent the national burden of LTBI among the study population given that they covered only two provinces of South Africa.Item The effect of multiple donning on respirator fit in national health laboratory service employees during 2016(2018) Vuma, Cynthia DansileIntroduction Healthcare providers, laboratories and other industries in South Africa use N95 filtering face-piece respirators to reduce or protect themselves against exposure to airborne diseases such as tuberculosis. This is despite the fact that the use of personal protective equipment such as respirators is the least preferred means of exposure control in the occupational hygiene hierarchy of controls. The National Health Laboratory Service (NHLS) provides diagnostic laboratory services to all national and provincial health departments in South Africa. Thus, NHLS employees are potentially exposed to infectious agents such as Mycobacterium tuberculosis and are provided with N95 respirators to protect themselves. NHLS employees in some laboratories tend to take one respirator and use it for the whole shift or multiple shifts. These practices raise some concerns of damage due to multiple respirator donnings that can result in poor fit. A study in the United States of America (USA) recommended that re-using of a respirator should be limited to not more than five times to ensure a continued good seal. Study aim The aim of this study was to determine if multiple donnings of the same respirator could influence the face seal resulting in poor fit of respirators worn by the National Institute for Occupational Health (NIOH) employees during 2016. Study objective To measure and describe the effect on respirator fit following multiple donning and doffing of the N95 respirator by NIOH employees using the same respirator. The Effect of Multiple Donning on Respirator Fit in NHLS Employees Materials and methods This was a cross-sectional qualitative experimental study with descriptive components. NHLS employees from one institute, namely the National Institute for Occupational Health (NIOH) were invited to participate in the study. Study participants involved both respirator users exposed to hazardous biological agents and non-respirator users. Non respirator users refer to non-exposed personnel to hazardous biological agents i.e. administration office, librarian. Data were collected on 25 employees who participated in this study. All participants underwent six consecutive fit tests using the same respirator each time whilst performing dynamic movements. Quantitative respirator fit testing was conducted using the PortaCount fit testing equipment. A fit factor of ≥ 100 was considered satisfactory following OSHA protocol. STATA version 14 was used to perform data analysis. Results and discussion The 25 study participants all passed the fit test on the first donning. The fit test results on average gradually deteriorated after multiple consecutive donnings but the average fit factor remained above the cut off 100. A significant difference in mean fit factor was seen between the first and sixth donning but not between the second and sixth donnings suggesting that the donning method deteriorated after the first donning. The proportion of participants achieving a fit factor below 100 were eight percent for fit test two, 24% for fit test three, 32% for fit test four and five, then decreased to 28% for fit test six; although 13 (52%) achieved an overall fit factor of above 100 for all six consecutive fit tests. Four participants achieved a good overall fit factor of above 200 after six donnings. This experimental study results are in agreement with the findings of a National Institute for Occupational Safety and Health (NIOSH) study, which investigated the impact of multiple consecutive donnings on filtering face-piece respirator fit, and recommended five donnings of one respirator. The NIOSH study also established that the fit of the filtering face-piece respirator gradually decreased after multiple donnings and the best levels of fit were observed for donnings one to five. Some participants (6.25%) of this study showed an increased fit after six donnings. The Effect of Multiple Donning on Respirator Fit in NHLS Employees Respirator fit was demonstrated to vary over the consecutive donnings for most participants suggesting that the method used to don the respirator is very important to achieving a good fit. A third of participants failed a fit test and then passed in a subsequent fit test indicating the mask retained the ability to fit while the donning skill of the participant varied with each donning. The best overall fit factors were observed for donnings one and two (Table 3.5). Occurrences of two or more consecutive fit test scores of less than 100 were observed on eight participants. Persistent fit tests failures were observed on four participants. Head strap and nosepiece breaks were not witnessed in this study. Conclusion A satisfactory fit test score was found in the sixth fit test in 72% of the study participants. Variability in the donning technique was demonstrated by the 30% of participants who passed a fit test after failing a previous fit test. The consecutive multiple donnings of respirators carried out in this study demonstrated that while the respirator retains the ability to form a seal, not all respirator users will maintain acceptable levels of respirator fit following multiple donnings and doffings of the same respirator. Users and employers need to be aware of the increasing risk of unsatisfactory fit following multiple donnings and doffing of these devices and invest in regular training and other control measures.Item Investigation of the role of human parvovirus B19 in chronic anaemia of hiv infected TB patients(1994-09-30) van Niekerk, Albetus. Bernhardus. Willer.This study was undertaken to determine the role of human parvovirus B19 (B19) in chronic anaemia of HIV infected TB patients. Patients were selected from an existing databank of 307 patients included in a MRC HIV/TB study. Twenty-nine patients, 15 coinfected with HIV/TB and 14 infected with TB only, were identified for further evaluation. These patients’ sera were subjected to serological and DNA detection studies using IgG and IgM ELISA methods and a nested polymerase chain reaction (PCR) assay.Item Antibodies to mycobacterium tuberculosis mycolic acids in patients with pulmonary tuberculosis(2001-09-11) Schleicher., Gunter, Klaus.Introduction and Aim: The waxy outer cell wall of mycobacteria consists mainly of mycolic acids (MA). The unique immuno-stimulatory properties of MA via the CD 1-restricted antigen presentation pathway have been demonstrated in humans. Purification and isolation of M.tuberculosis (MTB) MA has allowed them to be applied as an antigen in an ELISA-based sero-diagnostic assay to detect specific antibodies in the sera of humans. The aim of the study was to measure the levels of antibody to MA in the sera of patients with culture proven pulmonary tuberculosis (PTB), and in control subjects without evidence of tuberculosis.Item A phytochemical and pharmacological investigation of South African Vitex species(2004-09-03) Nyiligira., Eric.As part of investigation of the biological activities of South African plant, a phytochemical and pharmacological investigation was carried out on five indigenous Vitex species; V. obovata ssp. obovata, V.obovata ssp. wilmsii, V. pooara, V. rehmannii and V. zeyheri . The chemical composition of the essential oils was determined using gas chromatography and mass spectrometry, and 1.8-cineole, a- copaene , caryophyllene oxide and y-muurolene were found to be the most abundant constituents in the essential oils of both V. obovatassp. obovataand V. obovata sssp. wilmsii.Item The role of mononuclear cells in tuberculosis(1992-06-03) Sussman, GarthSonicates derived from Mycobacterium tuberculosis suppressed lymphocytes proliferation. Pulsing of monocytes with mycobacterial sonicates resulted in the release of high molecular weight lipids. Both these lipids and those prepared by column fractionation of mycobacterial sonicates suppressed lymphocyte blastogenesis.This effect was due to the activation and not the proliferation of CD8+ lymphocytes by the lipid containing mycobacterial fractions of Mr>200kDa that could be obtained in vitro by column fractions.Item Autoantibodies in pulmonary tuberculosis and leprosy in black South Africans(1988-12-01) Rapoport, B. L.Infections can cause autoantibody production. The purpose of this study was to determine the prevalence of autoantibodies in chronic mycobacterial infections in Johannesburg. Sera from 41 leprosy patients and from 49 untreated and 73 treated tuberculosis patients were tested for rheumatoid factor, antibodies against a panel of nuclear antigens, anticardiolipin antibodies and syphilis serology. The antinuclear antibody was positive in 7.3% of the leprosy group, 6.1% of the untreated TB group and 15% of the treated tuberculosis patients (p=0.0125). Antinuclear antibody positivity correlated with duration of treatment (p=0.025). The antinuclear antibody titres were low and there was no specific pattern.Item Factors influencing the collection of information by community health workers for tuberculosis contact tracing in Ekurhuleni, Johannesburg(2018) Maruma, Thabang WellingtonBackground: Surveillance structures for tuberculosis (TB) contact tracing are not well integrated into routine national reporting structures. The implementation of reingineering of primary health care through ward based outreach teams (WBOTs) is a step towards equitable primary health care. Data and information collected by WBOTs for household TB contact tracing is an integral part of the implementation model of primary health care reengineering. The quality of patient record documentation becomes even more vital in light of the increased focus on process and outcome measures in health programmes and as a result, careful consideration be given to the WBOT data collection system used by community health workers (CHWs). In order to contribute to efforts of developing an optimised model for household contact tracing, the acceptability of the current paper-based data collection system needs to be assessed in order to develop a comprehensive monitoring & evaluaiton (M&E) framework for an optimsed model for household tuberculosis contact tracing. Methods: The current cross sectional research project is nested within a project that aims to develop an optimised model for household TB contact tracing. In this nested mixed methods study; the exploratory sequential design was used to explore the facilitators and barriers to completing the current data collection tools used by CHWs. The study had two components, firstly three focus group discussions (FGDs) were conducted in the three Ekurhuleni health sub-districts (Northern, Eastern and Southern) in three purposively selected primary health clinics and secondary data analysis of the main study`s FGDs was also conducted. Manual coding and QDA Miner software was used for coding and all qualitative analysis. Emerging themes were identified through inductive thematic analysis using the constant comparison analysis framework. The results informed the quantitative data collection and analysis. Following qualitative analysis; a close ended questionnaire was refined and informed by the results of the qualitative inquiry. CHWs were recruited using targetted sampling techniques from 6 primary health care facilities located in the different sub-districts in order to administer the questionnaire. The four point Likert Scale questionnaire was developed using theoritical framework for acceptability (TFA) constructs to asses the level of acceptability of the current data collection tools used to document tuberculosis contact tracing activities. Univariate and multivariate linear regression models were fitted to examine significant relationships between the composite acceptability scores and several predictors. All quantitative analysis was perforned on STATA version 14 (StataCorp College Station, Texas 77845 USA). Results: A total of five FGDs were conducted; two that were conducted as part of the main study supplemented the data from the three that were conducted (one in each Ekurhuleni health Sub-district). The total of 54 CHWs participated in all the five FGDs with 89% being female. Average age of all CHWs was 34.41 years [mean (sd): 34.41(8.16)]. Five broad themes emerged including inadequate CHW training, WBOT programme integration with other health and social care service providers, challenges with the WBOT data collection system, community access issues and preference for a digital based data collection system. Data related barriers identified included limitations with the current paper based data collection system such as insufficient competency assessments about the different data collection tools, lack of a specific tool to capture TB contact tracing activities, incomplete referral forms due to clinic staff not completing them, patients providing wrong information, too many papers to complete. Those that were related to the WBOT actvities included lack of community acceptance, resource constraints, violent patients and community members, community members that are not welcoming . Facilitators included motivated CHWs. 94 CHWs were enrolled for the quantitative survey with 90 (95.74%) females. From the total, 35% of the CHWs were from the Ekurhuleni health southern subdistrict, 34% and 31% were from the eastern and northern sub-districts respectively. The overall median (IQR) composite acceptability scores from all sub-districts was 48 (45 51), with the highest scores observed in the Eastern sub-district 49 (45 46) . In the overall study population, the acceptability of the current WBOT data collection tools was low. Conclusions: Main findings pertaining to CHW training indicate that the different phases of the Primary Health Care (PHC) reingeering WBOT trainings were inconsistent. There is also a lack of acknowledgement of attendance as CHW expressed their dissatisfaction in not receiving certifications which resulted in low morale for conducting outreach activities. The sub-optimal integration of the WBOT programme into the primary health care system results in a patchy referral system characterised by incomplete back referrals resulted as referral forms remain incomplete. Communication between the primary health care facility staff and WBOT CHWs needs to be strengthened in order to strengthen the referral linkages with other health and social care service providers. Funding models for WBOT programme need to be reviewed to ensure that resources needed for optimal WBOT functioning are secured. Restricted access to some communities, patients providing wrong addresses, violent and unwelcoming household members and lack of WBOT safety were barriers to accessing TB patients during outreach activities; thus leading to incomplete and innacurate data. The limitations posed by the current paper-based data collection system have been acknowledged and the CHWs preference for a digital based system highlights the need for the evaluation of the current mobile data collection technologies in other regions in order to inform nationwide scale-up. Recommendations: The implementation of the WBOT programme is still in its infancy and in order to improve the data collection processes of the programme, more research on CHW post-training competence is needed to determine the effectiveness of the wide array of training programs. Moreover, the implementation of CHW program should be coordinated among the different training providers including government, civil society organizations and NGOs. To improve the quality of the CHW training delivery and content, CHW feedback should be sought through pre-and post-assessments. There is a need to focus efforts on coordinating and strengthening the different PHC reengineering streams and integrate them into the primary health care system. This will likely strengthen the referral system between the WBOT programme and PHC facilities. The current M&E policy needs to be reviewed and special consideration should be given to TB contact tracing related indicators. This should also be accompanied by an adjustment of the current WBOT data collection tools to better reflect the agreed upon TB contact tracing indicators. The study further recommends further research in the form of economic evaluations to determine the cost effectiveness of scaling up current digital based data collection methods to inform nationwide scale up. Key words: Ward Based Outreach Teams, data collection system, data collection tools, community health workers, TB contact tracing, Community Based Information System, acceptabiltity, mHealthItem Use and fit of filtering facepiece respirators in a department of anaesthesiology(2018) Niemandt, MarthinetBackground: Reliable protection against nosocomial tuberculosis transmission in theatre depends on the appropriate use of filtering facepiece respirators (FFRs) with an N95 filter, as recommended by the Centers for Disease Control and Prevention. Aim: To describe anaesthetist compliance and comfort with the use of FFRs, followed by donning technique and fit tests outcomes. Design: Prospective, contextual, descriptive, two part study. Setting: Part 1 was done in a university affiliated department of anaesthesiology. Part 2 was a pilot study in the theatre complex of a 1200-bed tertiary-level academic hospital. Participants: Part 1 – anaesthetists in the department selected by convenience sampling (n=140). Part 2 – anaesthetists selected by stratified random sampling (10 male and 10 female). Methods: In Part 1 a self-administered questionnaire was distributed. In Part 2 the donning technique was directly observed, corrected, then followed by qualitative fit testing with the single model and size FFR available. Results: Part 1 -Compliance with the use of the FFR was inadequate with a compliance score of 14.5 (SD 5.0) out of 25. FFRs are deemed to be uncomfortable (discomfort score of 9.9 (SD 4.0) out of 21.) Part 2 - Of the 20 anaesthetists, six (30%), five males and one female, passed the fit test. Conclusions: Compliance with FFR use was poor and anaesthetists at the research institution found the FFRs uncomfortable. FFR donning technique was observed to be lacking. Research with a larger study group is required. Poor fit test results were most likely due to the availability of only one size and model of FFR.Item Comparison of coronal minimum intensity projection CT reconstructions with flexible bronchoscopy for airway compression in children with Lymphobronchial TB(2018) Krim, Ahmed Omar AliINTRODUCTION Tuberculosis (TB) remains one of the most important causes of morbidity and mortality in children in Africa, as well as the rest of the world. Lymphobronchial TB (LBTB) occurs when tuberculous adenopathy affects the airways, either by direct involvement (inflammation and erosion) or by indirect involvement (compression and stenosis). Endobronchial TB (EBTB) is the inflammation of the tracheobronchial tree, which is caused by tuberculosis, and is secondary to the rupture of lymph nodes into the bronchi, or the extension thereof to the peribronchial region, by lymphatic drainage. Identification of airway compromise due to any of these processes can be performed invasively using flexible bronchoscopy or non-invasively with CT scanning, including post processing techniques such as minimum intensity projections (MinIP). AIM This retrospective study aimed to generate standardised coronal minimum intensity projection (MinIP) CT reconstructions, and compare these with fibreoptic bronchoscopy in children with LBTB. METHOD Standardised coronal MinIP reconstructions were performed from CT scans in children with LBTB and the findings of three readers were compared with flexible bronchoscopy (FB), regarding airway abnormalities. Intraluminal lesions, the site of the stenosis, and the degree of stenosis were evaluated. The length of stenosis was evaluated by CT MinIP only, and no comparison to FB has been made. RESULTS 65 children with LBTB met the inclusion criteria (38 males; 58.5% and 27 females; 41.5%), with ages ranging from 2.5 to 144 months. Coronal CT MinIP demonstrated a sensitivity of 96% and specificity of 89% against FB. The most common site of stenosis was the bronchus intermedius (91%), followed by the left main bronchus (85%), the right upper lobe bronchus RUL (66%), and the trachea (60%). Agreement between coronal CT MinIP and FB ranged from 36.9% at the carina to 84.6% at the RLL in normal and abnormal airways. CONCLUSION This study has proven that a standardised coronal CT MinIP reconstruction is useful in demonstrating airway stenosis in children with lymphobronchial TB, with sensitivity of up to 96% and specificity up to 89%. The most common sites of stenosis found by the coronal MinIP CT reconstruction were the BI (91%), followed by the LMB (85%), the RUL (66%), and the trachea (60%). The coronal CT MinIP had additional advantages over FB in that it allowed objective measurement of the diameter of the stenosis, measurement of the length of the stenosis as well as visualisation of the post-stenotic segments of the airways. CT MinIP was also able to provide information about lung parenchymal abnormalities. Standardised coronal MinIP reconstructions are easily performed, as described in our paper, and should be provided with each set of cross sectional MDCT images in children with LBTB. This one single image can provide easily appreciable and useful airway information and additional information not available from FB.