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Nemungadi TG, Kleppa E, Galappaththi-Arachchige HN, Pillay P, Gundersen SG, Vennervald BJ, Ndhlovu PD, Taylor M, Naidoo S, Kjetland EF. Predictors for participation in mass-treatment and female genital schistosomiasis re-investigation, and the effect of praziquantel treatment in South African adolescents. PLoS Negl Trop Dis 2024; 18:e0011798. [PMID: 38536861 PMCID: PMC11020363 DOI: 10.1371/journal.pntd.0011798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/16/2024] [Accepted: 03/12/2024] [Indexed: 04/18/2024] Open
Abstract
OBJECTIVE Female Genital Schistosomiasis (FGS) causes intravaginal lesions and symptoms that could be mistaken for sexually transmitted diseases or cancer. In adults, FGS lesions [grainy sandy patches (GSP), homogenous yellow patches (HYP), abnormal blood vessels and rubbery papules] are refractory to treatment. The effect of treatment has never been explored in young women; it is unclear if gynaecological investigation will be possible in this young age group (16-23 years). We explored the predictors for accepting anti-schistosomal treatment and/or gynaecological reinvestigation in young women, and the effects of anti-schistosomal mass-treatment (praziquantel) on the clinical manifestations of FGS at an adolescent age. METHOD The study was conducted between 2011 and 2013 in randomly selected, rural, high schools in Ilembe, uThungulu and Ugu Districts, KwaZulu-Natal Province, East Coast of South Africa. At baseline, gynaecological investigations were conducted in female learners in grades 8 to 12, aged 16-23 years (n = 2293). Mass-treatment was offered in the low-transmission season between May and August (a few in September, n = 48), in accordance with WHO recommendations. Reinvestigation was offered after a median of 9 months (range 5-14 months). Univariate, multivariable and logistic regression analysis were used to measure the association between variables. RESULTS Prevalence: Of the 2293 learners who came for baseline gynaecological investigations, 1045 (46%) had FGS lesions and/or schistosomiasis, 209/1045 (20%) had GSP; 208/1045 (20%) HYP; 772/1045 (74%) had abnormal blood vessels; and 404/1045 (39%) were urine positive. Overall participation rate for mass treatment and gynaecological investigation: Only 26% (587/2293) learners participated in the mass treatment and 17% (401/2293) participated in the follow up gynaecological reinvestigations. Loss to follow-up among those with FGS: More than 70% of learners with FGS lesions at baseline were lost to follow-up for gynaecological investigations: 156/209 (75%) GSP; 154/208 (74%) HYP; 539/722 (75%) abnormal blood vessels; 238/404 (59%) urine positive. The grade 12 pupil had left school and did not participate in the reinvestigations (n = 375; 16%). Follow-up findings: Amongst those with lesions who came for both treatment and reinvestigation, 12/19 still had GSP, 8/28 had HYP, and 54/90 had abnormal blood vessels. Only 3/55 remained positive for S. haematobium ova. Factors influencing treatment and follow-up gynaecological investigation: HIV, current water contact, water contact as a toddler and urinary schistosomiasis influenced participation in mass treatment. Grainy sandy patches, abnormal blood vessels, HYP, previous pregnancy, current water contact, water contact as a toddler and father present in the family were strongly associated with coming back for follow-up gynaecological investigation. Challenges in sample size for follow-up analysis of the effect of treatment: The low mass treatment uptake and loss to follow up among those who had baseline FGS reduced the chances of a larger sample size at follow up investigation. However, multivariable analysis showed that treatment had effect on the abnormal blood vessels (adjusted odds ratio = 2.1, 95% CI 1.1-3.9 and p = 0.018). CONCLUSION Compliance to treatment and gynaecological reinvestigation was very low. There is need to embark on large scale awareness and advocacy in schools and communities before implementing mass-treatment and investigation studies. Despite challenges in sample size and significant loss to follow-up, limiting the ability to fully understand the treatment's effect, multivariable analysis demonstrated a significant treatment effect on abnormal blood vessels.
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Affiliation(s)
- Takalani Girly Nemungadi
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Elisabeth Kleppa
- Norwegian Centre for Imported and Tropical Diseases, Oslo University Hospital, Oslo, Norway
| | | | - Pavitra Pillay
- Department of Biomedical and Clinical Technology, Durban University of Technology, KwaZulu-Natal, Durban, South Africa
| | - Svein Gunnar Gundersen
- Institute for Global Development and Planning, University of Agder, Kristiansand, Norway
| | - Birgitte Jyding Vennervald
- Section for Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Myra Taylor
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Saloshni Naidoo
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Eyrun Floerecke Kjetland
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
- Norwegian Centre for Imported and Tropical Diseases, Oslo University Hospital, Oslo, Norway
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Kiesolo FN, Sampa M, Moonga G, Michelo C, Jacobs C. Coverage and predictors of the uptake of the mass drug administration of praziquantel chemotherapy for schistosomiasis in a selected urban setting in Zambia. FRONTIERS IN EPIDEMIOLOGY 2023; 3:1168282. [PMID: 38455938 PMCID: PMC10910951 DOI: 10.3389/fepid.2023.1168282] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 03/27/2023] [Indexed: 03/09/2024]
Abstract
The burden of schistosomiasis in Zambia has remained high over the years. The World Health Assembly recommended adequate mass drug administration coverage for schistosomiasis using Praziquantel chemotherapy for school-aged children and all at-risks adults. We aimed at investigating the coverage and the factors associated to the uptake for MDA for schistosomiasis in Ng'ombe township of Lusaka, Zambia. A cross-sectional survey was conducted in May and June 2021 via phone calls to the residents of Ng'ombe township. Commcare software was used in the conduct of the survey. Pearson's Chi-square test and multiple logistic regression were conducted using the STATA version 15.0. 769 study participants were randomly selected using systematic sampling, of which 76.3% were younger than 40 years, 64.9% were female, 64.4% were married, 56.3% had reached the secondary educational level and 51.9% were employed. Coverage for MDA for schistosomiasis in Ng'ombe township in 2018 was found to be 49.8% (95% CI: 46.2%-53.4%). Positive predictors of the MDA were prior knowledge of the occurrence of the MDA in 2018 (aOR: 2.892, p < 0.001) and believing that the provision of incentives like snacks was important during the MDA with PZQ in Ng'ombe township (aOR: 1.926, p = 0.001), whereas age (aOR:0.979, p = 0.009), marital status (aOR:0.620, p = 0.006), employment status (aOR:0.587, p = 0.001) were negative predictors of the MDA. Elimination of the burden of schistosomiasis in endemic settings needs the attainment of an optimum coverage and uptake during MDA with PZQ. Therefore, prior knowledge about an impending intervention and the provision of incentives like snacks during the intervention should be prioritized by MDA implementers, while background characteristics such as age, marital status, and employment status need to be taken into consideration when planning and promoting uptake in future MDAs.
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Affiliation(s)
- Felix Nzonzi Kiesolo
- Department of Epidemiology and Biostatistics, School of Public Health, University of Zambia, Lusaka, Zambia
| | - Mutale Sampa
- Department of Epidemiology and Biostatistics, School of Public Health, University of Zambia, Lusaka, Zambia
| | - Given Moonga
- Department of Epidemiology and Biostatistics, School of Public Health, University of Zambia, Lusaka, Zambia
| | - Charles Michelo
- Strategic Centre for Health Systems Metrics & Evaluation, School of Public Health, University of Zambia, Lusaka, Zambia
- Harvest Research Institutes, Harvest University, Lusaka, Zambia
| | - Choolwe Jacobs
- Department of Epidemiology and Biostatistics, School of Public Health, University of Zambia, Lusaka, Zambia
- Women in Global Health, Lusaka, Zambia
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Nwoko OE, Manyangadze T, Chimbari MJ. Spatial distribution, abundance, and infection rates of human schistosome-transmitting snails and related physicochemical parameters in KwaZulu-Natal (KZN) province, South Africa. Heliyon 2022; 9:e12463. [PMID: 36793949 PMCID: PMC9922783 DOI: 10.1016/j.heliyon.2022.e12463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/08/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
This study investigated the spatial distribution, abundance, and infection rates of human schistosome-transmitting snails and related physicochemical parameters and environmental factors in 11 districts in KwaZulu-Natal (KZN) province, South Africa, from December 2020-February 2021. Snail sampling was carried out in 128 sites by two people for 15 min using scooping and handpicking methods. Geographical information system (GIS) was used to map surveyed sites. In situ measurements of physicochemical parameters were recorded, while remote sensing was used to obtain measurements for climatic factors required to achieve the study's objective. Cercarial shedding and snail-crushing methods were used to detect snail infections. Kruskal-Wallis test was used to test the differences in snail abundance among snail species, districts, and habitat types. A negative binomial generalized linear mixed model was used to identify the physicochemical parameters and environmental factors influencing the abundance of snail species. A total of 734 human schistosome-transmitting snails were collected. Bu. globosus were significantly more abundant (n = 488) and widely distributed (found in 27 sites) compared to B. pfeifferi (n = 246) found in 8 sites. Bu. globosus and B. pfeifferi had infection rates of 3.89% and 2.44%, respectively. Dissolved oxygen and normalized difference vegetation index showed a statistically positive relationship, while normalized difference wetness index showed a statistically negative relationship with the abundance of Bu. globosus. However, there was no statistically significant relationship between B. pfeifferi abundance, physicochemical parameters, and climatic factors. Our study described the current distribution, abundance, and infection status of human schistosome-transmitting snails in KZN province, which will contribute to informing control measure policies for schistosomiasis.
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Affiliation(s)
- Onyekachi Esther Nwoko
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa,Corresponding author.
| | - Tawanda Manyangadze
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa,Geography Department, Faculty of Science and Engineering, Bindura University of Science Education, Bag 1020, Bindura, Zimbabwe
| | - Moses John Chimbari
- Discipline of Public Health Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa,Department of Behavioural Science, Medical and Health Sciences, Great Zimbabwe University, P.O Box 1235, Masvingo, Zimbabwe
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Nemungadi TG, Furumele TE, Gugerty MK, Djirmay AG, Naidoo S, Kjetland EF. Establishing and Integrating a Female Genital Schistosomiasis Control Programme into the Existing Health Care System. Trop Med Infect Dis 2022; 7:tropicalmed7110382. [PMID: 36422933 PMCID: PMC9696272 DOI: 10.3390/tropicalmed7110382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/02/2022] [Accepted: 11/09/2022] [Indexed: 11/19/2022] Open
Abstract
Female genital schistosomiasis (FGS) is a complication of Schistosoma haematobium infection, and imposes a health burden whose magnitude is not fully explored. It is estimated that up to 56 million women in sub-Saharan Africa have FGS, and almost 20 million more cases will occur in the next decade unless infected girls are treated. Schistosomiasis is reported throughout the year in South Africa in areas known to be endemic, but there is no control programme. We analyze five actions for both a better understanding of the burden of FGS and reducing its prevalence in Africa, namely: (1) schistosomiasis prevention by establishing a formal control programme and increasing access to treatment, (2) introducing FGS screening, (3) providing knowledge to health care workers and communities, (4) vector control, and (5) water, sanitation, and hygiene. Schistosomiasis is focal in South Africa, with most localities moderately affected (prevalence between 10% and 50%), and some pockets that are high risk (more than 50% prevalence). However, in order to progress towards elimination, the five actions are yet to be implemented in addition to the current (and only) control strategy of case-by-case treatment. The main challenge that South Africa faces is a lack of access to WHO-accredited donated medication for mass drug administration. The establishment of a formal and funded programme would address these issues and begin the implementation of the recommended actions.
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Affiliation(s)
- Takalani Girly Nemungadi
- Discipline of Public Health Medicine, School of Nursing and Public Health, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
- Communicable Disease Control Directorate, National Department of Health, Pretoria 0001, South Africa
- Correspondence:
| | - Tsakani Ernica Furumele
- Communicable Disease Control Directorate, National Department of Health, Pretoria 0001, South Africa
| | - Mary Kay Gugerty
- Evans School of Public Policy & Governance, University of Washington, Seattle, WA 98195-3055, USA
| | - Amadou Garba Djirmay
- Department of the Control of Neglected Tropical Diseases, World Health Organization, 1211 Geneva, Switzerland
| | - Saloshni Naidoo
- Discipline of Public Health Medicine, School of Nursing and Public Health, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Eyrun Flörecke Kjetland
- Discipline of Public Health Medicine, School of Nursing and Public Health, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
- Norwegian Centre for Imported and Tropical Diseases, Department of Infectious Diseases Ullevaal, Oslo University Hospital, 0424 Oslo, Norway
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Fine-scale mapping of Schistosoma mansoni infections and infection intensities in sub-districts of Makenene in the Centre region of Cameroon. PLoS Negl Trop Dis 2022; 16:e0010852. [PMID: 36227962 PMCID: PMC9595529 DOI: 10.1371/journal.pntd.0010852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 10/25/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022] Open
Abstract
Background Schistosomiasis control relies mainly on mass drug administration of Praziquantel (PZQ) to school aged children (SAC). Although precision mapping has recently guided decision making, the sub-districts and the epidemiological differences existing between bio-ecological settings in which infected children come from were not taken into consideration. This study was designed to fill this gap by using POC-CCA and KK to comparatively determine the prevalence and infection intensities of Schistosoma mansoni (S. mansoni) and to perform fine-scale mapping of S. mansoni infections and its infection intensities with the overarching goal of identifying sub-districts presenting high transmission risk where control operations must be boosted to achieve schistosomiasis elimination. Methodology During a cross- sectional study conducted in Makenene, 1773 stool and 2253 urine samples were collected from SAC of ten primary schools. S. mansoni infections were identified using the point of care circulating cathodic antigen (POC-CCA) and Kato-Katz (KK) test respectively on urine and stool samples. Geographical coordinates of houses of infected SAC were recorded using a global position system device. Schistosome infections and infection intensities were map using QGIS software. Results The prevalence of S. mansoni inferred from POC-CCA and KK were 51.3% and 7.3% respectively. Most infected SAC and those bearing heavy infections intensities were clustered in sub-districts of Baloua, Mock-sud and Carrière. Houses with heavily-infected SAC were close to risky biotopes. Conclusion This study confirms the low sensitivity of KK test compared to POC-CCA to accurately identify children with schistosome infection and bearing different schistosome burden. Fine-scale mapping of schistosome infections and infection intensities enabled to identify high transmission sub-districts where control measures must be boosted to reach schistosomiasis elimination. Although some disparities in terms of prevalence and infection intensities have been acknowledged within and between schistosomiasis endemic areas, the current control measures did not take into consideration the disparities within endemic areas. To improve the control of schistosomiasis, a fine-scale mapping of schistosome infections and their intensities were undertaken using KK in comparison to POC-CCA to identify sub-districts with potential high transmission risk and where control operations must be boosted to achieve elimination. After the identification of schistosome infections by the point of care circulating cathodic antigen (POC-CCA) and Kato-Katz (KK) test, the geographical coordinates of each infected child’s house were recorded using a global position system device (GPS). QGIS software was used to create a map showing schistosome infections and their infection intensities. Our results showed that the majority of infected children and those bearing heavy infection intensities were clustering mostly in Baloua, Carrière and Mock-Sud sub-districts of Makenene while children with light and moderate infection intensity were widely distributed and far away from risky biotopes. The fine-scale mapping of schistosome infections and their infection intensities enable to identify hotspot transmission sites where control strategy must be boosted to achieve the elimination of intestinal schistosomiasis in Makenene.
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Gender-related differences in prevalence, intensity and associated risk factors of Schistosoma infections in Africa: A systematic review and meta-analysis. PLoS Negl Trop Dis 2021; 15:e0009083. [PMID: 34788280 PMCID: PMC8635327 DOI: 10.1371/journal.pntd.0009083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 12/01/2021] [Accepted: 09/29/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Schistosomiasis remains a global-health problem with over 90% of its burden concentrated in Africa. Field studies reflect the complex ways in which socio-cultural and socio-economic variables, affect the distribution of Schistosoma infections across different populations. This review set out to systematically investigate and quantify the differences in Schistosoma infection burdens between males and females in Africa for two of the most prevalent Schistosoma species-Schistosoma mansoni and Schistosoma haematobium. METHODOLOGY We searched (from inception to 11th March 2020) Embase, MEDLINE, PubMed, and Web of Science for relevant studies on schistosomiasis. We included studies that report S. mansoni and/or S. haematobium prevalence and/or intensity data distributed between males and females. We conducted meta-analyses on the male to female (M:F) prevalence of infection ratios. Subgroup analyses were performed according to study baseline prevalence, sample size and the lower and upper age limit of study participants. We also present a descriptive analysis of differential risk and intensity of infection across males and females. Evidence for differences in the prevalence of schistosomiasis infection between males and females is presented, stratified by Schistosoma species. RESULT We identified 128 relevant studies, with over 200,000 participants across 23 countries. Of all the reported differences in the prevalence of infection between males and females, only 41% and 34% were statistically significant for S. mansoni and S. haematobium, respectively. Similar proportions of studies (27% and 34% for for S. haematobium and S. mansoni, respectively) of the reported differences in intensity of infection between males and females were statistically significant. The meta-analyses summarized a higher prevalence of infection in males; pooled random-effects weighted M:F prevalence of infection ratios were 1.20 (95% CI 1.11-1.29) for S. haematobium and 1.15 (95% CI 1.08-1.22) for S. mansoni. However, females are underrespresented in some of the studies. Additionally, there was significant heterogeneity across studies (Higgins I2 statistic (p-values < 0.001, I2values>95%)). Results of the subgroup analysis showed that the baseline prevalence influenced the M:F prevalence ratios for S. haematobium and S. mansoni, with higher M:F prevalence of infection ratios in settings with a lower baseline prevalence of infection. Across the studies, we identified four major risk factors associated with infection rates: occupational and recreational water contact, knowledge, socio-economic factors and demographic factors. The effect of these risk factors on the burden of infection in males and females varied across studies. CONCLUSIONS We find evidence of differences in prevalence of infection between males and females which may reflect differences in gender norms and water contact activities, suggesting that policy changes at the regional level may help ameliorate gender-related disparities in schistosomiasis infection burden. Collecting, robustly analysing, and reporting, sex-disaggregated epidemiological data, is currently lacking, but would be highly informative for planning effective treatment programmes and establishing those most at risk of schistosomiasis infections.
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Profiro de Oliveira JH, Arruda IES, Izak Ribeiro de Araújo J, Chaves LL, de La Rocca Soares MF, Soares-Sobrinho JL. Why do few drug delivery systems to combat neglected tropical diseases reach the market? An analysis from the technology's stages. Expert Opin Ther Pat 2021; 32:89-114. [PMID: 34424127 DOI: 10.1080/13543776.2021.1970746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Many drugs used to combat schistosomiasis, Chagas disease, and leishmaniasis (SCL) have clinical limitations such as: high toxicity to the liver, kidneys and spleen; reproductive, gastrointestinal, and heart disorders; teratogenicity. In this sense, drug delivery systems (DDSs) have been described in the literature as a viable option for overcoming the limitations of these drugs. An analysis of the level of development (TRL) of patents can help in determine the steps that must be taken for promising technologies to reach the market. AREAS COVERED This study aimed to analyze the stage of development of DDSs for the treatment of SCL described in patents. In addition, we try to understand the main reasons why many DDSs do not reach the market. In this study, we examined DDSs for drugs indicated by WHO and treatment of SCL, by performing a search for patents. EXPERT OPINION In this present work we provide arguments that support the hypothesis that there is a lack of integration between academia and industry to finance and continue research, especially the development of clinical studies. We cite the translational research consortia as the potential alternative for developing DDSs to combat NTDs.
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Affiliation(s)
| | | | | | - Luise Lopes Chaves
- Department of Pharmacy, Federal University of Pernambuco, Recife, Recife-Pernambuco
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Torres-Vitolas CA, Dhanani N, Fleming FM. Factors affecting the uptake of preventive chemotherapy treatment for schistosomiasis in Sub-Saharan Africa: A systematic review. PLoS Negl Trop Dis 2021; 15:e0009017. [PMID: 33465076 PMCID: PMC7846123 DOI: 10.1371/journal.pntd.0009017] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 01/29/2021] [Accepted: 11/30/2020] [Indexed: 11/29/2022] Open
Abstract
Background Schistosomiasis affects nearly 220 million people worldwide, mainly in Sub-Saharan Africa (SSA). Preventive chemotherapy (PC) treatment, through regular mass-drug administration (MDA) of Praziquantel tablets remains the control measure of choice by Ministries of Health. Current guidelines recommend that 75% of school-aged children receive treatment. Many programmes, however, struggle to achieve this target. Given the risk of high reinfection rates, attaining sustained high levels of treatment coverage is essential. This study provides a comprehensive review of the barriers and facilitators operating at different levels of analysis, from the individual to the policy level, conditioning the uptake of PC for schistosomiasis in SSA. Methodology/Principal findings A systematic literature search was conducted in several databases for publications released between January 2002 and 2019 that examined factors conditioning the uptake of Praziquantel in the context of MDA campaigns in SSA. A total of 2,258 unique abstracts were identified, of which 65 were selected for full text review and 30 met all eligibility criteria. Joanna Briggs Institute’s Critical Appraisal and the Mixed-Methods Assessment tools were used to assess the strength of the evidence. This review was registered with PROSPERO (CRD42017058525). A meta-synthesis approach was used. Results indicated publication bias, with the literature focusing on East African rural settings and evidence at the individual and programmatic levels. The main influencing factors identified included material wellbeing, drug properties, knowledge and attitudes towards schistosomiasis and MDAs, fears of side effects, gender values, community and health systems support, alongside programme design features, like training, sensitisation, and provision of incentives for drug-distributors. The effect of these factors on determining Praziquantel uptake were explored in detail. Conclusions/Significance Multiple determinants of treatment uptake were found in each level of analysis examined. Some of them interact with each other, thus affecting outcomes directly and indirectly. The promotion of context-based transdisciplinary research on the complex dynamics of treatment uptake is not only desirable, but essential, to design effective strategies to attain high levels of treatment coverage. Schistosomiasis is a parasitic infection that affects nearly 220 million people worldwide. Long-term effects include anaemia, growth stunting, bladder cancer and infertility. Currently, the main approach to schistosomiasis control involves mass preventive chemotherapy treatment. Current guidelines recommend treating 75% of school-aged children but many programmes struggle to achieve this target. This study conducted a comprehensive review of factors conditioning the uptake of treatment in Sub-Saharan Africa across different levels of analysis: individual, interpersonal, organisational, community and policy. This examination showed, first, that the literature suffers of publication bias, with most studies based in rural East African sites and focusing in discussing individual- and policy-level factors. It indicated as well that people’s livelihoods, food security, and school-enrolment, alongside knowledge and attitudinal factors influenced treatment uptake at the individual level. Various contextual factors concerning interpersonal relations, organisations’ resources, and prevalent socio-cultural features (e.g., gender) further shaped people’s responses to MDA campaigns. Finally, it was observed that the effectiveness of programme-level decisions on sensitisation, training, and drug-delivery strategies were constantly re-shaped by mediating factors operating at lower levels of analysis. We conclude that the promotion of context-based transdisciplinary research is essential to design effective strategies to promote sustainable high levels of treatment coverage.
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Affiliation(s)
- Carlos A. Torres-Vitolas
- SCI Foundation, London, United Kingdom
- School of Public Health, Imperial College, London, United Kingdom
- * E-mail:
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Mazani E, Taylor M, Kjetland EF, Ndhlovu PD. Knowledge and perceptions about schistosomiasis among primary school children and teachers in rural KwaZulu-Natal. S Afr J Infect Dis 2020; 35:126. [PMID: 34485472 PMCID: PMC8377800 DOI: 10.4102/sajid.v35i1.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 01/07/2020] [Indexed: 11/19/2022] Open
Abstract
Background Schistosomiasis is a disease caused by parasitic trematode worms of the genus Schistosoma. In 2014, over 258 million people worldwide required treatment for the disease. Schistosomiasis is known to be prevalent in the northern region of KwaZulu-Natal province of South Africa, especially among school-going children but less is known about their knowledge of the disease and their attitude towards being treated for the disease at school. Methods The study was a descriptive and analytical cross-sectional survey conducted through self-administered questionnaires among grades 5 and 7 learners from 10 randomly selected rural primary schools in iLembe and uThungulu, KwaZulu-Natal. Teachers from the same schools participated during the same period. Results A total of 730 learners and 78 teachers took part in the study. Among the learners, 73.2% (95% confidence interval [CI]: 69.7% – 76.4%) correctly identified freshwater contact as a risk for schistosomiasis, but only 42.7% (95% CI: 38.8% – 46.8%) knew how to prevent it. Among the teachers, 96.8% (95% CI: 87.8% – 99.4%) knew the risk and 69.0% (95% CI: 55.3%– 80.1%) knew the prevention of schistosomiasis. Almost 70% (95% CI: 65.9% – 72.8%) of the learners and 67.6% (95% CI: 42.1% – 65.6%) of the teachers reported their willingness to receive treatment with praziquantel at school. Conclusion This study showed that basic knowledge about the risk of schistosomiasis among the participants was high, but the cause and prevention of the disease were less well understood. There is need to include schistosomiasis in health education both at school and through community awareness programmes.
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Affiliation(s)
- Edmore Mazani
- Department of Public Health Medicine, Faculty of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Myra Taylor
- Department of Public Health Medicine, Faculty of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Eyrun F Kjetland
- Department of Infectious Diseases, Norwegian Centre for Imported and Tropical Diseases, Oslo University Hospital, Oslo, Norway
| | - Patricia D Ndhlovu
- Department of Infectious Diseases, Faculty of Health Sciences, Imperial College London, London, United Kingdom
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The cost of a school based mass treatment of schistosomiasis in Ugu District, KwaZulu Natal, South Africa in 2012. PLoS One 2020; 15:e0232867. [PMID: 32497049 PMCID: PMC7271983 DOI: 10.1371/journal.pone.0232867] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 04/23/2020] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION The Neglected Tropical Diseases Roadmap of the WHO set targets for potential elimination as a "public health problem" for the period 2012-2020 in multiple countries in Africa, with the aim of global elimination of schistosomiasis as a "public health problem" by 2025. AIM The purpose of the study was to estimate the cost from a provider's perspective of the Department of Health's Schistosomiasis Mass Drug Administration (MDA) in Ugu District, KwaZulu-Natal in 2012, with a view to project the costs for the entire KwaZulu Natal Province. METHODS A total of 491 public schools and 16 independent schools in Ugu District, a predominantly rural district in KwaZulu-Natal with a total of 218 242 learners, were included in the schistosomiasis control programme. They were randomly selected from schools situated below an altitude of 300 meters, where schistosomiasis is endemic. A retrospective costing study was conducted using the provider's perspective to cost. Cost data were collected by reviewing existing records including financial statements, invoices, receipts, transport log books, equipment inventories, and information from personnel payroll, existing budget, and the staff diaries. RESULTS A total of 15571 children were treated in 2012, resulting in a total cost of the MDA programme of ZAR 2 137 143 and a unit cost of ZAR 137. The three main cost components were Medication Costs (37%), Human Resources Cost (36%) and Capital items (16%). The total cost for treating all eligible pupils in KwaZulu-Natal will be ZAR 149 031 888. However, should the capital cost be excluded, then the unit cost will be ZAR 112 per patient and this will translate to a total cost of ZAR 121 836 288. CONCLUSIONS Low coverage exacerbates the cost of the programme and makes a decision to support such a programme difficult. However, a normative costing study based on the integration of the programme within the Department of Health should be conducted.
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Ncube MV, Chimbari MJ. A prospective risk assessment of the implementation of a schistosomiasis preventive mass drug administration for children aged five years and below in the uMkhanyakude district of KwaZulu-Natal. BMC Health Serv Res 2019; 19:685. [PMID: 31590663 PMCID: PMC6781343 DOI: 10.1186/s12913-019-4507-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/03/2019] [Indexed: 11/17/2022] Open
Abstract
Background Schistosomiasis is endemic in the uMkhanyakude district of KwaZulu-Natal, South Africa. The South Africa Department of Health (DoH) has decided to implement a schistosomiasis preventive mass drug administration program in all affected parts of the country. Quality management is part of the strategic objectives of the treatment program. We conducted a risk assessment and developed guidelines for the quality management of a schistosomiasis preventive treatment program for children aged 5 years and below in the uMkhanyakude District of KwaZulu-Natal. Methods We conducted a scenario planning exercise by interviewing 10 child health experts from the uMkhanyakude Health District to establish potential risks associated with a planned schistosomiasis preventive control treatment program for children aged 5 years old and below. The risks were analyzed using a modified Failure Mode and Effect Analysis (FMEA). An FMEA table was produced to guide the quality management of the planned schistosomiasis preventive control treatment program for children aged 5 years and below in the uMkhanyakude Health District. Results We identified potential risks, failure modes and possible failure corrective/preventive measures in the following activities that would be part of the mass treatment of children aged 5 years and below infected with schistosomiasis in the uMkhanyakude District. These included enrolment of children into the treatment program; general health checks; weight and height measurements; administration of drugs; reporting of side effects and monitoring and evaluation. Conclusion We were able to use FMEA guide quality management and identify potential risks associated with the planned schistosomiasis preventive treatment program for children aged 5 years old and below in the uMkhanyakude District of KwaZulu-Natal. The FMEA for this program will be useful to the quality management of schistosomiasis preventive treatment programs for this age group in other similar settings.
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Affiliation(s)
- Mhlengi Vella Ncube
- School of Nursing and Public Health, College of Health Sciences, University of KwaZulu- Natal, Durban, South Africa.
| | - Moses John Chimbari
- School of Nursing and Public Health, College of Health Sciences, University of KwaZulu- Natal, Durban, South Africa
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Sacolo-Gwebu H, Kabuyaya M, Chimbari M. Knowledge, attitudes and practices on schistosomiasis and soil-transmitted helminths among caregivers in Ingwavuma area in uMkhanyakude district, South Africa. BMC Infect Dis 2019; 19:734. [PMID: 31438865 PMCID: PMC6704662 DOI: 10.1186/s12879-019-4253-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 07/03/2019] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Schistosomiasis and soil-transmitted helminth infections are among the most chronic infections worldwide. Based on their demonstrable impact on human health, the WHO recently recommended the implementation of robust strategies aimed at controlling or eliminating schistosomiasis and soil-transmitted helminths by 2020. The implementation of this strategy, however, warrants a clear understanding of the community's knowledge, attitudes and practices in relation to these infections. This study sought to identify sociocultural gaps that should be addressed to ensure the success of cost-effective community-based schistosomiasis-soil-transmitted helminths control and elimination programs. METHODS This was a cross-sectional mixed methodology study. Quantitative data were collected using a structured questionnaire from 442 caregivers of preschool aged children. In-depth interviews and focus group discussions were conducted among caregivers, preschool teachers, traditional authorities and community caregivers. All interviews were captured using an audio recorder to maximize accuracy. Quantitative data were analysed using bivariate and multivariate techniques while qualitative data were analysed thematically. RESULTS Findings reflected inadequate knowledge, attitudes and practices in relation to schistosomiasis and soil-transmitted helminths while awareness of schistosomiasis and soil-transmitted helminths was high (87.1 and 79.2% respectively). Correct knowledge on transmission, prevention, signs and symptoms and life cycle was low (below 50%) for both infections among those who had heard of the disease. From multivariate analysis, being aged at least 35 years increased the odds of reporting good practices on schistosomiasis by 65% (COR 1.652, 95% CI: 1.073-2.543) while receiving health information through community meetings (COR 0.072, 95% CI: 0.010-0.548) significantly reduced the odds of having good knowledge on schistosomiasis. CONCLUSIONS These findings are valuable in designing behavioural change approaches towards enhancing health outcomes through community-based interventions to ensure effective control and elimination of schistosomiasis and soil-transmitted helminths. There is a critical need for channelling efforts towards making health education the core of schistosomiasis and soil-transmitted helminths programs aimed at achieving intensified control or elimination of these infections by 2020.
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Affiliation(s)
- Hlengiwe Sacolo-Gwebu
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Muhubiri Kabuyaya
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Moses Chimbari
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
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13
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Inobaya MT, Chau TN, Ng SK, MacDougall C, Olveda RM, Tallo VL, Landicho JM, Malacad CM, Aligato MF, Guevarra JB, Ross AG. Mass drug administration and the sustainable control of schistosomiasis: an evaluation of treatment compliance in the rural Philippines. Parasit Vectors 2018; 11:441. [PMID: 30064469 PMCID: PMC6069569 DOI: 10.1186/s13071-018-3022-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/17/2018] [Indexed: 12/22/2022] Open
Abstract
Background Preventive chemotherapy is the current global control strategy for schistosomiasis. The WHO target coverage rate is at least 75% for school-aged children. In the Philippines, the reported national coverage rate (43.5%) is far below the WHO target. This study examined the factors associated with non-compliance to mass drug administration. Methods A cross-sectional survey was conducted in 2015 among 2189 adults in the province of Northern Samar, the Philippines using a structured face-to-face survey questionnaire. Results The overall rate of non-compliance to mass drug administration (MDA) in the last treatment round was 27%. Females (aOR = 1.67, P = 0.033) were more likely to be non-compliant. Respondents who believed that schistosomiasis was acquired by open defecation and poor sanitation (aOR = 1.41, P = 0.015), and by drinking unclean water (aOR = 2.09, P = 0.001) were more likely to refuse treatment. Uncertainties on whether schistosomiasis can be treated (aOR = 2.39, P = 0.033), their fear of adverse reactions to praziquantel (aOR = 1.94, P = 0.021), misconceptions about alternative forms of treatment (aOR = 1.45, P = 0.037), and that praziquantel is used for purposes other than deworming (aOR = 2.15, P = 0.021) were all associated with a higher odd of non-compliance. In contrary, being a farmer (aOR = 0.62, P =0.038), participation in past MDA (aOR = 0.30, P < 0.001), informed about impending MDA (aOR = 0.08, P < 0.001), and having heard of schistosomiasis (aOR = 0.22, P = 0.045) were all significantly associated with reduced non-compliance. Conclusions To improve drug compliance for schistosomiasis there is an urgent need for intensive health education campaigns before conducting MDA that would not only provide disease specific information, but also deal with prevailing misconceptions about transmission, prevention, treatment, and drug side-effects.
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Affiliation(s)
- Marianette T Inobaya
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia.,Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Thao N Chau
- Discipline of Public Health, School of Health Sciences, Flinders University, Adelaide, Australia
| | - Shu-Kay Ng
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Colin MacDougall
- Discipline of Public Health, School of Health Sciences, Flinders University, Adelaide, Australia
| | - Remigio M Olveda
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Veronica L Tallo
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Jhoys M Landicho
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Carol M Malacad
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Mila F Aligato
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Jerric B Guevarra
- Department of Health, Research Institute for Tropical Medicine, Muntinlupa City, Philippines
| | - Allen G Ross
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia.
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Lothe A, Zulu N, Øyhus AO, Kjetland EF, Taylor M. Treating schistosomiasis among South African high school pupils in an endemic area, a qualitative study. BMC Infect Dis 2018; 18:239. [PMID: 29801483 PMCID: PMC5970489 DOI: 10.1186/s12879-018-3102-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 04/17/2018] [Indexed: 12/02/2022] Open
Abstract
Background Schistosomiasis, a neglected tropical disease caused by parasites that infest open water sources such as rivers and dams may increase susceptibility to HIV. Mass-treatment with praziquantel tablets, recommended by the World Health Organization reduces the prevalence of schistosomiasis. The goal in endemic areas is 75% treatment participation in every treatment round (e.g. yearly). However, in rural Ugu district, KwaZulu-Natal, South-Africa there was low participation among pupils in a Department of Health Mass-Treatment Campaign for schistosomiasis. Methods Nested in a large study on schistosomiasis the study was conducted in 2012 over 4 months using qualitative methods with the Health Belief Model as the conceptual framework. Purposive sampling was done. Focus Group Discussions were undertaken at six schools in grades 10–12. Individual in-depth interviews were held with one teacher and two pupils at each school. In addition three traditional healers and a community health worker were interviewed. Results The severity of schistosomiasis was not recognised and neither was the pupils’ susceptibility. Barriers to treatment included confusing S, haematobium symptoms with sexually transmitted infections, teasing and stigma. Conclusions Increased knowledge, health literacy for treatment, and correct understanding about the severity of schistosomiasis may provide cues to action. The study indicates that comprehensive information may increase pupil participation in mass-treatment and decrease schistosomiasis prevalence. Trial registration This study was registered with clinicaltrials.gov registry database and the registration number is NCT01154907 30 June 2011.
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Affiliation(s)
- Andrea Lothe
- Norwegian Centre for Imported and Tropical Diseases, Department of Infectious Diseases Ullevaal, Oslo University Hospital, 0424, Oslo, Norway.,Institute for Global Development and Planning, University of Agder, 4630, Kristiansand, Norway
| | - Nqobile Zulu
- Centre for Communication, Media and Society, University of KwaZulu-Natal, Durban, 4001, South Africa
| | - Arne Olav Øyhus
- Institute for Global Development and Planning, University of Agder, 4630, Kristiansand, Norway
| | - Eyrun Floerecke Kjetland
- Norwegian Centre for Imported and Tropical Diseases, Department of Infectious Diseases Ullevaal, Oslo University Hospital, 0424, Oslo, Norway.,Discipline of Public Health Medicine, Howard College Campus, University of KwaZulu-Natal, Room 219, George Campbell Building, Science Drive, Durban, 4001, South Africa
| | - Myra Taylor
- Discipline of Public Health Medicine, Howard College Campus, University of KwaZulu-Natal, Room 219, George Campbell Building, Science Drive, Durban, 4001, South Africa.
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Mass drug administration and the global control of schistosomiasis: successes, limitations and clinical outcomes. Curr Opin Infect Dis 2018; 29:595-608. [PMID: 27584590 DOI: 10.1097/qco.0000000000000312] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
PURPOSE OF REVIEW Preventive chemotherapy is advocated for the global control and elimination of schistosomiasis. Despite the well known short-term benefits of treating patients for schistosomiasis, the impact of mass drug administration (MDA) campaigns to control the disease in the long term remains unresolved. RECENT FINDINGS Many studies have advocated the success of MDA programs in order to attract donor funds for elimination efforts but such successes are often short-lived given the drug does not alter the life cycle of the organism or prevent reinfection. Within a matter of months to years after halting treatment, the prevalence, intensity of infection and morbidity of disease return to baseline levels. Other mitigating factors contribute to the failings of MDA campaigns namely: poverty, poor drug coverage, poor drug compliance, and, in the case of Asiatic schistosomiasis, zoonotic transmission. Genetic and innate and acquired immunologic mechanisms complicate the epidemiologic picture of schistosomiasis globally, and may contribute indirectly to MDA shortcomings. The possibility of drug resistance is an ever present concern because of the sole reliance on one drug, praziquantel. SUMMARY Preventive chemotherapy is advocated for the global control and elimination of schistosomiasis. The short-term benefits of MDA campaigns are well documented but the long-term benefits are questionable.
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Kabuyaya M, Chimbari MJ, Manyangadze T, Mukaratirwa S. Efficacy of praziquantel on Schistosoma haematobium and re-infection rates among school-going children in the Ndumo area of uMkhanyakude district, KwaZulu-Natal, South Africa. Infect Dis Poverty 2017; 6:83. [PMID: 28385154 PMCID: PMC5383960 DOI: 10.1186/s40249-017-0293-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 03/22/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Despite its low cure rates and possible resistance, praziquantel (PZQ) is the only drug available for schistosomiasis treatment. Hence, monitoring its efficacy is crucial. This study assessed the efficacy of PZQ, determined re-infection and incidence rates of Schistosoma haematobium infection among school-going children in the Ndumo area, KwaZulu-Natal. METHODS A cohort of 320 school-going children (10 - 15 years) in 10 primary schools was screened for S. haematobium infection using the filtration technique. Infected children were treated at different times and hence were divided into two sub-cohorts; A1 and A2. Non-infected children constituted the sub-cohort B. Children who continued excreting viable eggs 4 weeks post-treatment received a second dose of PZQ. Re-infection rates were determined in sub-cohort A1 and A2 at 28 and 20 weeks post-treatment, respectively. Cure rates (CR) and egg reduction rates (ERR) were calculated. Incidence rate was assessed 28 weeks post baseline survey using children that were negative for schistosome eggs at that survey. Analysis of data was done using the Chi square and the Wilcoxon rank test. A 95% confidence interval with a P-value < 0.05 determined significance. RESULTS At baseline, 120 (37.5%) of the 320 study participants were found infected with Schistosoma haematobium. Heavy infections accounted for 36.7%. The calculated cure rates were 88.07% and 82.92% for females and males, respectively. Egg Reduction Rates of 80% and 64% for females and males were observed 4 weeks after the initial treatment. After the second treatment, CR was 100% in females and 50% in males with an ERR of 100% in females and 70% in males. At 20 and 28 weeks post treatment, reinfection rates of 8.03% and 8.00% were observed, respectively, giving an overall rate of 8.1%. An incidence rate of 4.1% was observed 28 weeks after the baseline screening. CONCLUSIONS The study indicated high CR while the ERR was low suggesting a reduced PZQ efficacy. The efficacy improved among females after the second dose. Re-infection rates at 20 and 28 weeks post-treatment were low. The study also indicated a low incidence rate for the 28 weeks period.
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Affiliation(s)
- Muhubiri Kabuyaya
- Discipline of Public Health Medicine, Howard College, University of KwaZulu-Natal, Durban, P.O Box, 4041 South Africa
| | - Moses John Chimbari
- College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Tawanda Manyangadze
- Discipline of Public Health Medicine, Howard College, University of KwaZulu-Natal, Durban, P.O Box, 4041 South Africa
| | - Samson Mukaratirwa
- School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
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