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Vere M, ten Ham-Baloyi W, Melariri PE. Effects of paediatric schistosomiasis control programmes in sub-Saharan Africa: A systematic review. PLoS One 2024; 19:e0301464. [PMID: 38696510 PMCID: PMC11065241 DOI: 10.1371/journal.pone.0301464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 03/17/2024] [Indexed: 05/04/2024] Open
Abstract
Preventive chemotherapy by mass drug administration is globally recommended as the primary method of reaching the elimination of schistosomiasis, especially in the high risk-paediatric population. This systematic review provides a summary of the effects of paediatric schistosomiasis control programs on eliminating schistosomiasis in sub-Saharan Africa. A systematic search was conducted in PubMed, EBSCOhost, and other databases to obtain studies regarding the effects of paediatric schistosomiasis control programmes in sub-Saharan Africa. 3455 studies were screened for eligibility, included articles reported on both paediatrics control programmes and schistosomiasis, and articles were excluded when they did not report on schistosomiasis control programmes in paediatrics exclusively. 40 selected studies were critically appraised using the JBI critical appraisal tools for relevance and 30 studies were included in the study. An in-depth quantitative descriptive analysis was conducted, and a comprehensive narrative summary explained the results within the scope of the review questions. The results show that despite preventive chemotherapy lowering schistosomiasis prevalence, chances of re-infection are high in endemic areas. Preventive chemotherapy without complementary interventions including safe water provision and proper sanitation, snail control and health education on the aetiology of schistosomiasis, transmission pattern and control practices might not eliminate schistosomiasis.
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Affiliation(s)
- Maryline Vere
- Faculty of Health Sciences, Department of Environmental Health, Nelson Mandela University, University Way, Summerstrand, Gqeberha, South Africa
| | - Wilma ten Ham-Baloyi
- Faculty of Health Sciences, Department of Environmental Health, Nelson Mandela University, University Way, Summerstrand, Gqeberha, South Africa
- Faculty of Health Sciences, Department of Nursing Science, Nelson Mandela University, University Way, Summerstrand, Gqeberha, South Africa
| | - Paula Ezinne Melariri
- Faculty of Health Sciences, Department of Nursing Science, Nelson Mandela University, University Way, Summerstrand, Gqeberha, South Africa
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2
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Wiegand RE, Odiere MR, Kinung’hi S, N'Goran EK, Mwinzi P, Secor WE. Age-group associations of schistosomiasis prevalence from trial data, Côte d'Ivoire, Kenya and the United Republic of Tanzania. Bull World Health Organ 2024; 102:265-275. [PMID: 38562204 PMCID: PMC10976868 DOI: 10.2471/blt.23.289843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 07/11/2023] [Accepted: 01/16/2024] [Indexed: 04/04/2024] Open
Abstract
Objective To determine if the prevalence of schistosomiasis in children aged 9-12 years is associated with the prevalence in 5-8-year-olds and adults after preventive chemotherapy in schools or the community. Methods We combined data from four community-randomized, preventive chemotherapy trials in treatment-naïve populations in Côte d'Ivoire, Kenya and the United Republic of Tanzania during 2010-2016 according to the number of praziquantel treatments and the delivery method. Schistosoma mansoni infection was sought on two slides prepared from each participant's first stool using the Kato-Katz technique. We assessed associations between S. mansoni prevalence in 9-12-year-olds and 5-8-year-olds and adults in the community before and after treatment using Bayesian regression models. Findings Stool samples from 47 985 5-8-year-olds, 81 077 9-12-year-olds and 20 492 adults were analysed. We found associations between the prevalence in 9-12-year-olds and that in 5-8-year-olds and adults after preventive treatment, even when only school-age children were treated. When the prevalence in 9-12-year-olds was under 10%, the prevalence in 5-8-year-olds was consistently under 10%. When the prevalence in 9-12-year-olds was under 50%, the prevalence in adults after two or four rounds of preventive chemotherapy was 10%-15% lower than before chemotherapy. Post-chemotherapy age-group associations were consistent with pre-chemotherapy associations in this analysis and previous studies. Conclusion The prevalence of S. mansoni infection in 9-12-year-olds was associated with the prevalence in other age groups and could be used to guide community treatment decisions.
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Affiliation(s)
- Ryan E Wiegand
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS H24-5, Atlanta, Georgia, GA30329, United States of America
| | - Maurice R Odiere
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Safari Kinung’hi
- National Institute for Medical Research, Mwanza Centre, Mwanza, United Republic of Tanzania
| | | | - Pauline Mwinzi
- Expanded Special Programme for Elimination of Neglected Tropical Diseases, World Health Organization Regional Office for Africa, Brazzaville, Congo
| | - W Evan Secor
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS H24-5, Atlanta, Georgia, GA30329, United States of America
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Singer BJ, Coulibaly JT, Park HJ, Andrews JR, Bogoch II, Lo NC. Development of prediction models to identify hotspots of schistosomiasis in endemic regions to guide mass drug administration. Proc Natl Acad Sci U S A 2024; 121:e2315463120. [PMID: 38181058 PMCID: PMC10786280 DOI: 10.1073/pnas.2315463120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/13/2023] [Indexed: 01/07/2024] Open
Abstract
Schistosomiasis is a neglected tropical disease affecting over 150 million people. Hotspots of Schistosoma transmission-communities where infection prevalence does not decline adequately with mass drug administration-present a key challenge in eliminating schistosomiasis. Current approaches to identify hotspots require evaluation 2-5 y after a baseline survey and subsequent mass drug administration. Here, we develop statistical models to predict hotspots at baseline prior to treatment comparing three common hotspot definitions, using epidemiologic, survey-based, and remote sensing data. In a reanalysis of randomized trials in 589 communities in five endemic countries, a regression model predicts whether Schistosoma mansoni infection prevalence will exceed the WHO threshold of 10% in year 5 ("prevalence hotspot") with 86% sensitivity, 74% specificity, and 93% negative predictive value (NPV; assuming 30% hotspot prevalence), and a regression model for Schistosoma haematobium achieves 90% sensitivity, 90% specificity, and 96% NPV. A random forest model predicts whether S. mansoni moderate and heavy infection prevalence will exceed a public health goal of 1% in year 5 ("intensity hotspot") with 92% sensitivity, 79% specificity, and 96% NPV, and a boosted trees model for S. haematobium achieves 77% sensitivity, 95% specificity, and 91% NPV. Baseline prevalence is a top predictor in all models. Prediction is less accurate in countries not represented in training data and for a third hotspot definition based on relative prevalence reduction over time ("persistent hotspot"). These models may be a tool to prioritize high-risk communities for more frequent surveillance or intervention against schistosomiasis, but prediction of hotspots remains a challenge.
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Affiliation(s)
- Benjamin J. Singer
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA94304
| | - Jean T. Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Swiss Tropical and Public Health Institute, Basel, Allschwil4123Switzerland
- University of Basel, Basel4001, Switzerland
| | - Hailey J. Park
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA94304
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA94304
| | - Isaac I. Bogoch
- Department of Medicine, University of Toronto, Toronto, ONM5S 1A8, Canada
| | - Nathan C. Lo
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA94304
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Trippler L, Knopp S, Welsche S, Webster BL, Stothard JR, Blair L, Allan F, Ame SM, Juma S, Kabole F, Ali SM, Rollinson D, Pennance T. The long road to schistosomiasis elimination in Zanzibar: A systematic review covering 100 years of research, interventions and control milestones. ADVANCES IN PARASITOLOGY 2023; 122:71-191. [PMID: 37657854 DOI: 10.1016/bs.apar.2023.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Zanzibar is among the few places in sub-Saharan Africa where interruption of Schistosoma transmission seems an achievable goal. Our systematic review identifies and discusses milestones in schistosomiasis research, control and elimination efforts in Zanzibar over the past 100 years. The search in online databases, libraries, and the World Health Organization Archives revealed 153 records published between May 1928 and August 2022. The content of records was summarised to highlight the pivotal work leading towards urogenital schistosomiasis elimination and remaining research gaps. The greatest achievement following 100 years of schistosomiasis interventions and research is undoubtedly the improved health of Zanzibaris, exemplified by the reduction in Schistosoma haematobium prevalence from>50% historically down to<5% in 2020, and the absence of severe morbidities. Experiences from Zanzibar have contributed to global schistosomiasis guidelines, whilst also revealing challenges that impede progression towards elimination. Challenges include: transmission heterogeneity requiring micro-targeting of interventions, post-treatment recrudescence of infections in transmission hotspots, biological complexity of intermediate host snails, emergence of livestock Schistosoma species complicating surveillance whilst creating the risk for interspecies hybridisation, insufficient diagnostics performance for light intensity infections and female genital schistosomiasis, and a lack of acceptable sanitary alternatives to freshwater bodies. Our analysis of the past revealed that much can be achieved in the future with practical implementation of integrated interventions, alongside operational research. With continuing national and international commitments, interruption of S. haematobium transmission across both islands is within reach by 2030, signposting the future demise of urogenital schistosomiasis across other parts of sub-Saharan Africa.
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Affiliation(s)
- Lydia Trippler
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland.
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | | | - Bonnie L Webster
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | | | | | - Fiona Allan
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; University of St Andrews, St Andrews, United Kingdom
| | - Shaali Makame Ame
- Neglected Diseases Programme, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Saleh Juma
- Neglected Diseases Programme, Zanzibar Ministry of Health, Mkoroshoni, Pemba, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Programme, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Said Mohammed Ali
- Public Health Laboratory - Ivo de Carneri, Wawi, Chake Chake, Pemba, United Republic of Tanzania
| | - David Rollinson
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; Global Schistosomiasis Alliance, London, United Kingdom
| | - Tom Pennance
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; Western University of Health Sciences, Lebanon, OR, United States.
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5
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Chanhanga N, Mindu T, Mogaka J, Chimbari M. The Impact of Targeted Treatment and Mass Drug Administration Delivery Strategies on the Prevalence and Intensity of Schistosomiasis in School Aged Children in Africa: A Systematic Review. Infect Drug Resist 2023; 16:2453-2466. [PMID: 37138838 PMCID: PMC10150034 DOI: 10.2147/idr.s395382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 03/16/2023] [Indexed: 05/05/2023] Open
Abstract
Schistosomiasis is a public health problem in more than 78 countries in the world. The disease is most prevalent among children than adults due to their high exposure to infectious water sources. Various interventions such as mass drug administration (MDA), snail control, safe water provision and health education have been implemented independently or jointly to control, reduce and ultimately eliminate Schistosomiasis. This scoping review focused on studies reporting the impact of different delivery strategies of targeted treatment and MDA on the prevalence and intensity of schistosomiasis infection in school aged children in Africa. The review focused on Schistosoma haematobium and Schistosoma mansoni species. A systematic search for eligible literature from peer-reviewed articles was done from Google Scholar, Medline, PubMed and EBSCO host databases. The search yielded twenty-seven peer-reviewed articles. All articles found reported a decrease in the prevalence of schistosomiasis infection. Five studies (18.5%) reported a prevalence change below 40%, eighteen studies (66.7%) reported a change between 40% and 80%, and four studies (14.8%) reported a change above 80%. The infection intensity post-treatment was varied: twenty-four studies reported a decrease, while two studies reported an increase. The review showed that the impact of targeted treatment on the prevalence and intensity of schistosomiasis depended on the frequency at which it was offered, complementary interventions, and its uptake by the target population. Targeted treatment can significantly control the infection burden, but cannot eliminate the disease. Constant MDA programs coupled with preventative and health promotional programs are required to reach the elimination stage.
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Affiliation(s)
- Nathan Chanhanga
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
| | - Tafadzwa Mindu
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
- Correspondence: Tafadzwa Mindu, Email
| | - John Mogaka
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
| | - Moses Chimbari
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
- Research and Innovation, Great Zimbabwe University, Masvingo, Zimbabwe
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6
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Naqvi FA, Das JK, Salam RA, Raza SF, Lassi ZS, Bhutta ZA. Interventions for Neglected Tropical Diseases Among Children and Adolescents: A Meta-analysis. Pediatrics 2022; 149:186947. [PMID: 35503336 DOI: 10.1542/peds.2021-053852e] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/16/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Neglected tropical diseases (NTDs) are a group of communicable diseases affecting the poorest populations around the world. OBJECTIVE To assess the effectiveness of interventions, including mass drug administration (MDA), water, sanitation, and hygiene (WASH), vector control, health education, and micronutrients supplementation, for NTDs among children and adolescents. METHODS We conducted a literature search on the Cochrane Controlled Trials Register, Medline, and other databases until December 2020. We included randomized controlled trials and quasi-experimental studies conducted among children and adolescents. Two authors independently screened studies for relevance. Two authors independently extracted data, assessed the risk of bias, performed metaanalysis, and rated the quality of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation. RESULTS We included 155 studies (231 articles) involving 262 299 participants. For soil-transmitted helminthiasis, MDA may reduce the prevalence of Ascaris, Trichuris, and hookworm by 58%, 36%, and 57%, respectively. We are uncertain of the effect of health education, WASH, and iron supplementation on soil-transmitted helminthiasis prevalence. For Schistosomiasis, health education probably reduces the intensity and prevalence of S. mansoni, whereas micronutrient supplementation may reduce anemia prevalence and the infection intensity of S. hematobium compared with no supplementation. We are uncertain of the effect of MDA and vector control on Schistosomiasis outcomes. For trachoma, health education probably reduces the prevalence of active Trachoma, whereas we are uncertain of the effect of MDA, WASH, and vector control on Trachoma outcomes. There is limited data on the effectiveness of interventions for NTDs targeting children and adolescents. CONCLUSION Future studies are needed to evaluate the relative effectiveness and cost-effectiveness of various interventions specifically targeting children and adolescents.
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Affiliation(s)
- Fatima Abbas Naqvi
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Jai K Das
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Rehana A Salam
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Syeda Fatima Raza
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Zohra S Lassi
- Robinson Research Institute, the University of Adelaide, Adelaide, Australia.,Adelaide Medical School, The University of Adelaide, Adelaide, Australia
| | - Zulfiqar A Bhutta
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan.,Centre for Global Child Health, The Hospital for Sick Children (SickKids), Toronto, Ontario, Canada
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7
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Mutuku MW, Laidemitt MR, Spaan JM, Mwangi IN, Ochanda H, Steinauer ML, Loker ES, Mkoji GM. Comparative Vectorial Competence of Biomphalaria sudanica and Biomphalaria choanomphala, Snail Hosts of Schistosoma mansoni, From Transmission Hotspots In Lake Victoria, Western Kenya. J Parasitol 2021; 107:349-357. [PMID: 33906231 DOI: 10.1645/20-138] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Schistosoma mansoni, which causes human intestinal schistosomiasis, continues to be a major public health concern in the Lake Victoria basin in western Kenya, with Biomphalaria sudanica (a shoreline inhabiting snail) and Biomphalaria choanomphala (a deep-water snail) playing roles in transmission. A recent study showed that B. sudanica was abundantly present near all study villages on the lakeshore, but B. choanomphala was significantly more abundant near villages known to be persistent transmission hotspots. The present study investigated the relative compatibility of B. sudanica and B. choanomphala with S. mansoni. A reciprocal cross-infection experiment used young adult F1 generation B. sudanica and B. choanomphala that were exposed to either 1, 5, or 10 sympatric or allopatric human-derived S. mansoni miracidia. Three weeks post-exposure (PE) and weekly thereafter, the snails were counted and screened for schistosome cercariae, and at 7 wk PE, total cercariae shed during a 2 hr period by each infected snail was determined. Pre-patent periods for S. mansoni in both B. sudanica and B. choanomphala were similar, and most snails in all exposure combinations started shedding cercariae 5 wk PE. Prevalences were significantly higher in B. choanomphala (12.2-80.9%) than in B. sudanica (5.2-18.6%) at each dose, regardless of whether miracidia were of an allopatric or a sympatric source (P < 0.0001). Overall, the odds of a snail becoming infected with 5 or 10 miracidia were significantly higher than the odds of being infected with 1 miracidium, (P < 0.0001), and fewer cercariae were produced by snails exposed to single as compared to 5 or 10 miracidia. On average, B. choanomphala produced more cercariae ( = 458, SD = 414) than B. sudanica ( = 238, SD = 208) (P < 0.0001). These results suggest that B. choanomphala is more compatible with S. mansoni than B. sudanica. Though B. choanomphala can be found in shallow shoreline waters, it is, for the most part, a deeper-water taxon. Because dredging is a relatively inefficient means of sampling, B. choanomphala is likely underestimated with respect to its population size, the number of S. mansoni-positive snails, and its role in maintaining transmission.
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Affiliation(s)
- Martin W Mutuku
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya.,School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya
| | - Martina R Laidemitt
- Center for Evolutionary and Theoretical Immunology, Parasitology Division, Museum of Southwestern Biology, Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| | - Johannie M Spaan
- Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon 97355
| | - Ibrahim N Mwangi
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Horace Ochanda
- School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya
| | - Michelle L Steinauer
- Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon 97355
| | - Eric S Loker
- Center for Evolutionary and Theoretical Immunology, Parasitology Division, Museum of Southwestern Biology, Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131
| | - Gerald M Mkoji
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
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Manjang B, Ochola EA, Elliott SJ. The use of non-pharmaceutical interventions for the prevention and control of schistosomiasis in sub-Saharan Africa: A systematic review. Glob Public Health 2021; 17:469-482. [PMID: 33460349 DOI: 10.1080/17441692.2020.1869799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Schistosomiasis remains a major cause of global parasitic morbidity. Current control strategies focus on pharmaceutical approaches using Mass Drug Administration (MDA) to distribute praziquantel in endemic areas of sub-Saharan Africa. Our paper systematically reviewed the literature on non-pharmaceutical interventions for enhanced schistosomiasis control. We conducted a systematic review of peer-reviewed English language literature using PubMed, Embase and Web of Science. Our search terms were limited to the year 2000 to March 2019 to reflect the period of the Millennium and Sustainable Development Goals. We initially identified 1733 publications, which were reduced to 1324 after screening by title and abstract. After the inclusion and exclusion criteria, a total of 1312 studies were excluded. Following this, we had a total of 12 articles, which we later screened by full text. Out of the twelve articles, seven were excluded for being systematic reviews or examining clinical and nutritional aspects of schistosomiasis control. We finally remained with five studies that met our inclusion criteria. Our paper indicates a gap in non-pharmaceutical based interventions for schistosomiasis control. We propose that future research addresses this gap by engaging communities in participatory approaches such as environmental sanitation, Water, Sanitation and Hygiene (WASH), health education and economic empowerment.
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Affiliation(s)
- Buba Manjang
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, Canada
| | - Elizabeth A Ochola
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, Canada
| | - Susan J Elliott
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, Canada
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9
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Ouattara M, Diakité NR, Yao PK, Saric J, Coulibaly JT, Assaré RK, Bassa FK, Koné N, Guindo-Coulibaly N, Hattendorf J, Utzinger J, N’Goran EK. Effectiveness of school-based preventive chemotherapy strategies for sustaining the control of schistosomiasis in Côte d'Ivoire: Results of a 5-year cluster randomized trial. PLoS Negl Trop Dis 2021; 15:e0008845. [PMID: 33449924 PMCID: PMC7810315 DOI: 10.1371/journal.pntd.0008845] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 09/30/2020] [Indexed: 11/18/2022] Open
Abstract
Background Preventive chemotherapy using praziquantel is the mainstay for schistosomiasis control. However, there is little evidence on what is supposed to be the most effective school-based treatment strategy to sustain morbidity control. The aim of this study was to compare differences in Schistosoma mansoni prevalence and infection intensity between three different schedules of school-based preventive chemotherapy in an area with moderate prevalence of S. mansoni in Côte d’Ivoire. Methodology Seventy-five schools were randomly assigned to one of three intervention arms: (i) annual school-based preventive chemotherapy with praziquantel (40 mg/kg) over four years; (ii) praziquantel treatment only in the first two years, followed by two years whithout treatment; and (iii) praziquantel treatment in years 1 and 3 without treatment in-between. Cross-sectional parasitologic surveys were carried out prior to each round of preventive chemotherapy. The difference in S. mansoni prevalence and infection intensity was assessed by multiple Kato-Katz thick smears, among children aged 9–12 years at the time of each survey. First-grade children, aged 5–8 years who had never received praziquantel, were also tested at baseline and at the end of the study. Principal findings Overall, 7,410 children aged 9–12 years were examined at baseline and 7,223 at the final survey. The baseline prevalence of S. mansoni was 17.4%, 20.2%, and 25.2% in arms 1, 2, and 3, respectively. In the final year, we observed the lowest prevalence of 10.4% in arm 1, compared to 18.2% in arm 2 and 17.5% in arm 3. The comparison between arms 1 and 2 estimated an odds ratio (OR) of 0.52 but the difference was not statistically significant (95% confidence interval (CI) = 0.23–1.16). Likewise the difference between arms 1 and 3 lacked statistical significance (OR = 0.55, 95% CI = 0.23–1.29). There was no noteworthy difference observed between arms 2 and 3 (OR = 1.06, 95% CI = 0.64–1.75). The lowest S. mansoni fecal egg counts in the final year survey were observed in arm 1 (7.9 eggs per gram of stool (EPG)). However, compared with 11.5 EPG in arm 2 and 15.4 EPG in arm 3, the difference lacked statistical significance. There were 4,812 first-grade children examined at baseline and 4,513 in the final survey. The overall prevalence of S. mansoni in these children slightly decreased in arms 1 (from 4.5% to 3.6%) and 2 (from 4.7% to 4.3%), but increased in arm 3 (from 6.8% to 7.9%). However, there was no significant difference in prevalence and infection intensity observed between study arms. Conclusions/significance The three treatment schedules investigated led to a reduction in the prevalence and intensity of S. mansoni infection among children aged 9–12 years. Comparing intervention arms at the end of the study, no statistically significant differences were observed between annual treatement and the other two treatment schedules, neither in reduction of prevalence nor intensity of infection. It is important to combine our results with those of three sister trials conducted simultaneously in other African countries, before final recommendations can be drawn. The World Health Organization (WHO) recommends preventive chemotherapy with praziquantel as the global strategy for morbidity control of schistosomiasis. The guidelines include target groups and treatment frequencies based on prevalence in school-age children. However, these recommendations are based on expert opinion. The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) put forward a series of cluster-randomized trials in different African countries, including Côte d’Ivoire, to identify the most suitable approach to gain and sustain the control of schistosomiasis. Results from Côte d’Ivoire did not show statistically significant differences between three school-based treatment schedules (i.e., annual treatment over four years; treatment only in the first two years, followed by two years whithout treatment; and treatment every other year without treatment in-between) in reducing prevalence and intensity of Schistosoma mansoni infection among children aged 9–12 years. The results in first-grade children with an age of 5–8 years entering school who had never received deworming drugs showed no significant difference in the prevalence and intensity of S. mansoni infection between the different treatments at the study end, suggesting that the three strategies were not significantly different for reducing the disease transmission in affected communities. However, our data should be combined with other SCORE studies carried out elsewhere in Africa. A meta-analysis including the results of the sister trials could help to conclude and make more generic recommendations.
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Affiliation(s)
- Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- * E-mail:
| | - Nana R. Diakité
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Patrick K. Yao
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Jasmina Saric
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jean T. Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Rufin K. Assaré
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Fidèle K. Bassa
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Naférima Koné
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Négnorogo Guindo-Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Eliézer K. N’Goran
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
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10
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King CH, Kittur N, Binder S, Campbell CH, N'Goran EK, Meite A, Utzinger J, Olsen A, Magnussen P, Kinung'hi S, Fenwick A, Phillips AE, Gazzinelli-Guimaraes PH, Dhanani N, Ferro J, Karanja DMS, Mwinzi PNM, Montgomery SP, Wiegand RE, Secor WE, Hamidou AA, Garba A, Colley DG. Impact of Different Mass Drug Administration Strategies for Gaining and Sustaining Control of Schistosoma mansoni and Schistosoma haematobium Infection in Africa. Am J Trop Med Hyg 2020; 103:14-23. [PMID: 32400356 PMCID: PMC7351298 DOI: 10.4269/ajtmh.19-0829] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This report summarizes the design and outcomes of randomized controlled operational research trials performed by the Bill & Melinda Gates Foundation–funded Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) from 2009 to 2019. Their goal was to define the effectiveness and test the limitations of current WHO-recommended schistosomiasis control protocols by performing large-scale pragmatic trials to compare the impact of different schedules and coverage regimens of praziquantel mass drug administration (MDA). Although there were limitations to study designs and performance, analysis of their primary outcomes confirmed that all tested regimens of praziquantel MDA significantly reduced local Schistosoma infection prevalence and intensity among school-age children. Secondary analysis suggested that outcomes in locations receiving four annual rounds of MDA were better than those in communities that had treatment holiday years, in which no praziquantel MDA was given. Statistical significance of differences was obscured by a wider-than-expected variation in community-level responses to MDA, defining a persistent hot spot obstacle to MDA success. No MDA schedule led to elimination of infection, even in those communities that started at low prevalence of infection, and it is likely that programs aiming for elimination of transmission will need to add supplemental interventions (e.g., snail control, improvement in water, sanitation and hygiene, and behavior change interventions) to achieve that next stage of control. Recommendations for future implementation research, including exploration of the value of earlier program impact assessment combined with intensification of intervention in hot spot locations, are discussed.
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Affiliation(s)
- Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Eliézer K N'Goran
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.,Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Aboulaye Meite
- Programme National de Lutte Contre les Maladies Tropicales Négligées à Chimiothérapie Préventive (PNLMTN-CP), Abidjan, Côte d'Ivoire
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Annette Olsen
- Section for Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pascal Magnussen
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Alan Fenwick
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | - Anna E Phillips
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | | | - Neerav Dhanani
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | - Josefo Ferro
- Catholic University of Mozambique, Beira, Mozambique
| | - Diana M S Karanja
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Pauline N M Mwinzi
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | - Ryan E Wiegand
- Centers for Disease Control and Prevention, Atlanta, Georgia.,University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Amina A Hamidou
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), Niamey, Niger
| | - Amadou Garba
- Department of Control of Neglected Tropical Diseases, Preventive Chemotherapy and Transmission Control Unit, World Health Organization, Geneva, Switzerland
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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11
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Secor WE, Wiegand RE, Montgomery SP, Karanja DMS, Odiere MR. Comparison of School-Based and Community-Wide Mass Drug Administration for Schistosomiasis Control in an Area of Western Kenya with High Initial Schistosoma mansoni Infection Prevalence: A Cluster Randomized Trial. Am J Trop Med Hyg 2020; 102:318-327. [PMID: 31802733 PMCID: PMC7008345 DOI: 10.4269/ajtmh.19-0626] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We conducted a cluster randomized trial comparing the target population and timing of mass drug administration (MDA) with praziquantel for control of schistosomiasis in villages in western Kenya with high initial prevalence (> 25%) according to a harmonized protocol developed by the Schistosomiasis Consortium for Operational Research and Evaluation. A total of 150 villages were randomized into six treatment arms (25 villages per arm), were assessed at baseline, and received two or four rounds of MDA using community-wide (CWT) or school-based (SBT) treatment over 4 years. In the fifth year, a final evaluation was conducted. The primary outcomes were prevalence and intensity of Schistosoma mansoni infections in children aged 9–12 years, each year their village received MDA. Baseline and year 5 assessments of first-year students and adults were also performed. Using Poisson and negative binomial regression with generalized estimating equations, we found similar effects of CWT and SBT MDA treatment strategies in children aged 9–12 years: significant reductions of prevalence of infection in all arms and of heavy-intensity (≥ 400 eggs/gram) infections in most arms but no significant differences between arms. Combined arms of villages that received four rounds of treatment had greater reduction than villages in arms that only received two rounds of treatment. Surprisingly, we also found benefits of SBT for first-year primary students and adults, who never received treatment in those arms. Our data support the use of annual SBT for control programs when coupled with attention to infections in younger children and occasional treatment of adults.
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Affiliation(s)
- W Evan Secor
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ryan E Wiegand
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Susan P Montgomery
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Diana M S Karanja
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Maurice R Odiere
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
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12
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Binder S, Campbell CH, Castleman JD, Kittur N, Kinung'hi SM, Olsen A, Magnussen P, Karanja DMS, Mwinzi PNM, Montgomery SP, Secor WE, Phillips AE, Dhanani N, Gazzinelli-Guimaraes PH, Clements MN, N'Goran EK, Meite A, Utzinger J, Hamidou AA, Garba A, Fleming FM, Whalen CC, King CH, Colley DG. Lessons Learned in Conducting Mass Drug Administration for Schistosomiasis Control and Measuring Coverage in an Operational Research Setting. Am J Trop Med Hyg 2020; 103:105-113. [PMID: 32400352 PMCID: PMC7351302 DOI: 10.4269/ajtmh.19-0789] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was created to conduct research that could inform programmatic decision-making related to schistosomiasis. SCORE included several large cluster randomized field studies involving mass drug administration (MDA) with praziquantel. The largest of these were studies of gaining or sustaining control of schistosomiasis, which were conducted in five African countries. To enhance relevance for routine practice, the MDA in these studies was coordinated by or closely aligned with national neglected tropical disease (NTD) control programs. The study protocol set minimum targets of at least 90% for coverage among children enrolled in schools and 75% for all school-age children. Over the 4 years of intervention, an estimated 3.5 million treatments were administered to study communities. By year 4, the median village coverage was at or above targets in all studies except that in Mozambique. However, there was often a wide variation behind these summary statistics, and all studies had several villages with very low or high coverage. In studies where coverage was estimated by comparing the number of people treated with the number eligible for treatment, denominator estimation was often problematic. The SCORE experiences in conducting these studies provide lessons for future efforts that attempt to implement strong research designs in real-world contexts. They also have potential applicability to country MDA campaigns against schistosomiasis and other NTDs, most of which are conducted with less logistical and financial support than was available for the SCORE study efforts.
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Affiliation(s)
- Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Jennifer D Castleman
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Safari M Kinung'hi
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
| | - Annette Olsen
- Section for Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pascal Magnussen
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Diana M S Karanja
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Pauline N M Mwinzi
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Susan P Montgomery
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - William Evan Secor
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Anna E Phillips
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | - Neerav Dhanani
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | | | - Michelle N Clements
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | - Eliézer K N'Goran
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.,Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Aboulaye Meite
- Programme National de Lutte contre les Maladies Tropicales Négligées à Chimiothérapie Préventive, Abidjan, Côte d'Ivoire
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Amina A Hamidou
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), Niamey, Niger
| | - Amadou Garba
- Department of Control of Neglected Tropical Diseases, Preventive Chemotherapy and Transmission Control Unit, World Health Organization, Geneva, Switzerland
| | - Fiona M Fleming
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | - Christopher C Whalen
- Department of Epidemiology and Biostatistics, Global Health Institute, University of Georgia, Athens, Georgia
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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13
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Tushabe JV, Lubyayi L, Sserubanja J, Kabuubi P, Abayo E, Kiwanuka S, Nassuuna J, Kaweesa J, Corstjens P, van Dam G, Sanya RE, Ssenyonga W, Tukahebwa EM, Kabatereine NB, Elliott AM, Webb EL. Does Intensive Treatment Select for Praziquantel Resistance in High-Transmission Settings? Parasitological Trends and Treatment Efficacy Within a Cluster-Randomized Trial. Open Forum Infect Dis 2020; 7:ofaa091. [PMID: 32296727 PMCID: PMC7148002 DOI: 10.1093/ofid/ofaa091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/10/2020] [Indexed: 11/14/2022] Open
Abstract
Background Praziquantel mass drug administration (MDA) is recommended in schistosomiasis-endemic areas. Animal models demonstrate Schistosoma parasite resistance to praziquantel after repeated exposure. Methods We conducted a parasitological survey in 26 fishing communities in Uganda after 4 years of quarterly (13 communities) or annual (13 communities) praziquantel MDA, with Schistosoma infection detected by single-stool-sample Kato-Katz. A test of cure was done in participants who were positive on both urine circulating cathodic antigen test and 3-sample Kato-Katz. We calculated cure rates (CRs) and egg reduction rates (ERRs) based on 3-sample Kato-Katz and infection intensity using worm-specific circulating anodic antigen (CAA) in blood, comparing these between quarterly and annually treated participants. Results Single-sample Kato-Katz Schistosoma mansoni prevalence was 22% in 1,056 quarterly treated participants and 34% in 1,030 annually treated participants (risk ratio, 0.62; 95% confidence interval [CI], 0.40 to 0.94). Among 110 test-of-cure participants, CRs were 65% and 51% in annually and quarterly treated villages, respectively (odds ratio, 0.65; 95% CI, 0.27 to 1.58); ERRs were 94% and 81% (difference, –13%; 95% CI, –48% to 2%). There was no impact of quarterly vs annual praziquantel on S. mansoni by CAA. Conclusions In this schistosomiasis hot spot, there was little evidence of decreased praziquantel efficacy. However, in the absence of alternative therapies, there remains a need for continued vigilance of praziquantel efficacy in the MDA era.
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Affiliation(s)
- John Vianney Tushabe
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda.,Wellcome Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Lawrence Lubyayi
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda.,Department of Epidemiology and Biostatistics, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Joel Sserubanja
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Prossy Kabuubi
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Elson Abayo
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Samuel Kiwanuka
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Jacent Nassuuna
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - James Kaweesa
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | - Paul Corstjens
- Leiden University Medical Center, Leiden, the Netherlands
| | - Govert van Dam
- Leiden University Medical Center, Leiden, the Netherlands
| | - Richard E Sanya
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda.,Department of Internal Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - William Ssenyonga
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | | | | | - Alison M Elliott
- Immunomodulation and Vaccines Research Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda.,Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK
| | - Emily L Webb
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
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14
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Kittur N, King CH, Campbell CH, Kinung'hi S, Mwinzi PNM, Karanja DMS, N'Goran EK, Phillips AE, Gazzinelli-Guimaraes PH, Olsen A, Magnussen P, Secor WE, Montgomery SP, Utzinger J, Walker JW, Binder S, Colley DG. Persistent Hotspots in Schistosomiasis Consortium for Operational Research and Evaluation Studies for Gaining and Sustaining Control of Schistosomiasis after Four Years of Mass Drug Administration of Praziquantel. Am J Trop Med Hyg 2020; 101:617-627. [PMID: 31287046 PMCID: PMC6726953 DOI: 10.4269/ajtmh.19-0193] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Control of schistosomiasis presently relies largely on preventive chemotherapy with praziquantel through mass drug administration (MDA) programs. The Schistosomiasis Consortium for Operational Research and Evaluation has concluded five studies in four countries (Côte d’Ivoire, Kenya, Mozambique, and Tanzania) to evaluate alternative approaches to MDA. Studies involved four intervention years, with final evaluation in the fifth year. Mass drug administration given annually or twice over 4 years reduced average prevalence and intensity of schistosome infections, but not all villages that were treated in the same way responded similarly. There are multiple ways by which responsiveness to MDA, or the lack thereof, could be measured. In the analyses presented here, we defined persistent hotspots (PHS) as villages that achieved less than 35% reduction in prevalence and/or less than 50% reduction in infection intensity after 4 years of either school-based or community-wide MDA, either annually or twice in 4 years. By this definition, at least 30% of villages in each of the five studies were PHSs. We found no consistent relationship between PHSs and the type or frequency of intervention, adequacy of reported MDA coverage, and prevalence or intensity of infection at baseline. New research is warranted to identify PHSs after just one or a few rounds of MDA, and new adaptive strategies need to be advanced and validated for turning PHSs into responder villages.
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Affiliation(s)
- Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Safari Kinung'hi
- National Institute for Medical Research, Mwanza Research Centre, Mwanza, Tanzania
| | - Pauline N M Mwinzi
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Diana M S Karanja
- Neglected Tropical Diseases Branch, Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Eliezer K N'Goran
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.,Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Anna E Phillips
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research, Imperial College London, London, United Kingdom
| | - Pedro H Gazzinelli-Guimaraes
- Department of Infectious Disease Epidemiology, Schistosomiasis Control Initiative, Imperial College London, London, United Kingdom
| | - Annette Olsen
- Section for Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pascal Magnussen
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - W Evan Secor
- Parasitic Diseases Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Susan P Montgomery
- Parasitic Diseases Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Juerg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Joseph W Walker
- Odum School of Ecology, University of Georgia, Athens, Georgia.,Department of Epidemiology, College of Public Health, University of Georgia, Athens, Georgia
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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15
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Differential impact of mass and targeted praziquantel delivery on schistosomiasis control in school-aged children: A systematic review and meta-analysis. PLoS Negl Trop Dis 2019; 13:e0007808. [PMID: 31603895 PMCID: PMC6808504 DOI: 10.1371/journal.pntd.0007808] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 10/23/2019] [Accepted: 09/25/2019] [Indexed: 02/07/2023] Open
Abstract
Background Schistosomiasis is a widespread public health concern in the poorest regions of the world. The principal control strategy is regular praziquantel administration to school-aged children in endemic areas. With calls for the elimination of schistosomiasis as a public health problem, expanding praziquantel delivery to all community members has been advocated. This systematic review and meta-analysis compares the impact of community-wide and child-targeted praziquantel distribution on schistosomiasis prevalence and intensity in school-aged children. Methodology/Principal findings We searched MEDLINE, Embase and Web of Science to identify papers that reported schistosome prevalence before and after praziquantel administration, either to children only or to all community members. Extracted data included Schistosoma species, drug administration strategy, number of treatment rounds, follow-up interval and prevalence and intensity before and after treatment. We used inverse variance weighted generalised linear models to examine the impact of mass versus targeted drug administration on prevalence reduction, and weighted boxplots to examine the impact on infection intensity reduction. This study is registered with PROSPERO, number CRD42018095377. In total, 34 articles were eligible for systematic review and 28 for meta-analysis. Schistosoma mansoni was reported in 20 studies; Schistosoma haematobium in 19 studies, and Schistosoma japonicum in two studies. Results of generalised linear models showed no detectable difference between mass and targeted treatment strategies on prevalence reduction in school-aged children for S. mansoni (odds ratio 0.47, 95%CI 0.13–1.68, p = 0.227) and S. haematobium (0.41, 95%CI 0.06–3.03, p = 0.358). Box plots also showed no apparent differences in intensity reduction between the two treatment strategies. Conclusions/Significance The results of this meta-analysis do not support the hypothesis that community-wide treatment is more effective than targeted treatment at reducing schistosomiasis infections in children. This may be due to the relatively small number of included studies, insufficient treatment coverage, persistent infection hotspots and unmeasured confounders. Further field-based studies comparing mass and targeted treatment are required. Schistosomiasis is a neglected tropical disease, caused by parasitic worms, that affects more than 143 million people worldwide. Chronic infections can lead to significant morbidity including kidney damage, anaemia, malnutrition, infertility and growth impairment. School-aged children between six and 15 years are often targeted for regular treatment with praziquantel in large-scale drug delivery programs, because they suffer a disproportionate burden of morbidity. On the other hand, a mass drug delivery strategy that treats all members of the community has been suggested in a move towards elimination of schistosomiasis as a public health problem. In this systematic review, we assess the impact of community-wide versus children-only praziquantel distribution in reducing schistosomiasis infections in school-aged children. We did not detect a difference between mass and targeted treatment strategies, possibly due to factors including insufficient treatment coverage and persistent sources of reinfection. Addressing these factors may assist in optimising control programs.
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16
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Olsen A, Kinung'hi S, Magnussen P. Comparison of the Impact of Different Mass Drug Administration Strategies on Infection with Schistosoma mansoni in Mwanza Region, Tanzania-A Cluster-Randomized Controlled Trial. Am J Trop Med Hyg 2019; 99:1573-1579. [PMID: 30350779 PMCID: PMC6283472 DOI: 10.4269/ajtmh.18-0671] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Annual school-based mass drug administration with praziquantel has been widely implemented to control schistosomiasis, but other treatment strategies could have a different impact. The aim of this study was to investigate the impact of six different treatment strategies on Schistosoma mansoni infection in a cluster-randomized controlled trial in schoolchildren, in a high transmission area of the Mwanza Region, Tanzania. A total of 150 villages were randomized into six arms with 25 villages in each arm. In each village, approximately 100 schoolchildren aged 9-12 years were randomly selected each year and investigated for S. mansoni prevalence and intensity based on three consecutive stool samples using the duplicate Kato-Katz technique. Four years of community-wide treatment (CWT) was the most intensive treatment strategy, whereas 2 years of school-based treatment (SBT) combined with 2 years without treatment (holiday) was the least intensive treatment. The remaining strategies constituted different combinations of CWT, SBT, and holiday years. Baseline results on S. mansoni infection were obtained from 14,620 schoolchildren from 148 villages, and mean prevalence and mean intensity among infected were 48.6-60.6% and 130.5-229.8 eggs per gram, respectively. Over the years, mean prevalence and mean intensities declined in all arms, but when comparing year 5 mean prevalence and mean intensity, there were no statistically significant differences between treatment arms. Thus, measured in a random selection of schoolchildren aged 9-12 years, four times CWT was not superior to four times SBT, while 2 years of treatment holiday combined with 2 years of SBT had the same impact as 4 years of SBT.
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Affiliation(s)
- Annette Olsen
- Department of Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Safari Kinung'hi
- National Institute for Medical Research, Mwanza Research Centre, Mwanza, Tanzania
| | - Pascal Magnussen
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Parasitology and Aquatic Pathobiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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17
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Sanya RE, Nkurunungi G, Hoek Spaans R, Nampijja M, O’Hara G, Kizindo R, Oduru G, Kabuubi Nakawungu P, Niwagaba E, Abayo E, Kabagenyi J, Zziwa C, Tumusiime J, Nakazibwe E, Kaweesa J, Muwonge Kakooza F, Akello M, Lubyayi L, Verweij J, Nash S, van Ree R, Mpairwe H, Tukahebwa E, Webb EL, Elliott AM. The Impact of Intensive Versus Standard Anthelminthic Treatment on Allergy-related Outcomes, Helminth Infection Intensity, and Helminth-related Morbidity in Lake Victoria Fishing Communities, Uganda: Results From the LaVIISWA Cluster-randomized Trial. Clin Infect Dis 2019; 68:1665-1674. [PMID: 30202872 PMCID: PMC6495012 DOI: 10.1093/cid/ciy761] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 09/03/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The prevalence of allergy-related diseases is increasing in low-income countries. Parasitic helminths, common in these settings, may be protective. We hypothesized that intensive, community-wide, anthelminthic mass drug administration (MDA) would increase allergy-related diseases, while reducing helminth-related morbidity. METHODS In an open, cluster-randomized trial (ISRCTN47196031), we randomized 26 high-schistosomiasis-transmission fishing villages in Lake Victoria, Uganda, in a 1:1 ratio to receive community-wide intensive (quarterly single-dose praziquantel plus albendazole daily for 3 days) or standard (annual praziquantel plus 6 monthly single-dose albendazole) MDA. Primary outcomes were recent wheezing, skin prick test positivity (SPT), and allergen-specific immunoglobulin E (asIgE) after 3 years of intervention. Secondary outcomes included helminths, haemoglobin, and hepatosplenomegaly. RESULTS The outcome survey comprised 3350 individuals. Intensive MDA had no effect on wheezing (risk ratio [RR] 1.11, 95% confidence interval [CI] 0.64-1.93), SPT (RR 1.10, 95% CI 0.85-1.42), or asIgE (RR 0.96, 95% CI 0.82-1.12). Intensive MDA reduced Schistosoma mansoni infection intensity: the prevalence from Kato Katz examinations of single stool samples from each patient was 23% versus 39% (RR 0.70, 95% CI 0.55-0.88), but the urine circulating cathodic antigen test remained positive in 85% participants in both trial arms. Hookworm prevalence was 8% versus 11% (RR 0.55, 95% CI 0.31-1.00). There were no differences in anemia or hepatospenomegaly between trial arms. CONCLUSIONS Despite reductions in S. mansoni intensity and hookworm prevalence, intensive MDA had no effect on atopy, allergy-related diseases, or helminth-related pathology. This could be due to sustained low-intensity infections; thus, a causal link between helminths and allergy outcomes cannot be discounted. Intensive community-based MDA has a limited impact in high-schistosomiasis-transmission fishing communities, in the absence of other interventions. CLINICAL TRIALS REGISTRATION ISRCTN47196031.
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Affiliation(s)
- Richard E Sanya
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
- Department of Internal Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Gyaviira Nkurunungi
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Remy Hoek Spaans
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Margaret Nampijja
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Geraldine O’Hara
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Robert Kizindo
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Gloria Oduru
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Prossy Kabuubi Nakawungu
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Emmanuel Niwagaba
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Elson Abayo
- Entebbe Hospital, Wakiso District Local Government, Uganda
| | - Joyce Kabagenyi
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Christopher Zziwa
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | | | | | - James Kaweesa
- Vector Control Division, Ministry of Health, Kampala, Uganda
| | | | - Mirriam Akello
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Lawrence Lubyayi
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | - Jaco Verweij
- Laboratory for Medical Microbiology and Immunology, St Elisabeth Hospital, Tilburg, The Netherlands
| | - Stephen Nash
- Medical Research Council Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Ronald van Ree
- Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Harriet Mpairwe
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
| | | | - Emily L Webb
- Medical Research Council Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Alison M Elliott
- Immunomodulation and Vaccines Programme, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, United Kingdom
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18
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Knopp S, Ame SM, Hattendorf J, Ali SM, Khamis IS, Bakar F, Khamis MA, Person B, Kabole F, Rollinson D. Urogenital schistosomiasis elimination in Zanzibar: accuracy of urine filtration and haematuria reagent strips for diagnosing light intensity Schistosoma haematobium infections. Parasit Vectors 2018; 11:552. [PMID: 30352631 PMCID: PMC6199745 DOI: 10.1186/s13071-018-3136-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 10/04/2018] [Indexed: 01/08/2023] Open
Abstract
Background Urine filtration and microhaematuria reagent strips are basic standard diagnostic methods to detect urogenital schistosomiasis. We assessed their accuracy for the diagnosis of light intensity infections with Schistosoma haematobium as they occur in individuals living in Zanzibar, an area targeted for interruption of transmission. Methods Urine samples were collected from children and adults in surveys conducted annually in Zanzibar from 2013 through 2016 and examined with the urine filtration method to count S. haematobium eggs and with the reagent strip test (Hemastix) to detect microhaematuria as a proxy for infection. Ten percent of the urine filtration slides were read twice. Sensitivity was calculated for reagent strips, stratified by egg counts reflecting light intensity sub-groups, and kappa statistics for the agreement of urine filtration readings. Results Among the 39,207 and 18,155 urine samples examined from children and adults, respectively, 5.4% and 2.7% were S. haematobium egg-positive. A third (34.7%) and almost half (46.7%) of the egg-positive samples from children and adults, respectively, had ultra-low counts defined as 1–5 eggs per 10 ml urine. Sensitivity of the reagent strips increased significantly for each unit log10 egg count per 10 ml urine in children (odds ratio, OR: 4.7; 95% confidence interval, CI: 4.0–5.7; P < 0.0001) and adults (OR: 2.6; 95% CI: 1.9–3.7, P < 0.0001). Sensitivity for diagnosing ultra-light intensity infections was very low in children (50.1%; 95% CI: 46.5–53.8%) and adults (58.7%; 95% CI: 51.9–65.2%). Among the 4477 and 1566 urine filtration slides read twice from children and adults, most were correctly identified as negative or positive (kappa = 0.84 for children and kappa = 0.81 for adults). However, 294 and 75 slides had discrepant results and were positive in only one of the two readings. The majority of these discrepant slides (76.9% of children and 84.0% of adults) had counts of 1–5 eggs per 10 ml urine. Conclusions We found that many individuals infected with S. haematobium in Zanzibar excrete > 5 eggs per 10 ml urine. These ultra-light infections impose a major challenge for accurate diagnosis. Next-generation diagnostic tools to be used in settings where interruption of transmission is the goal should reliably detect infections with ≤ 5 eggs per 10 ml urine. Trial Registration ISRCTN, ISRCTN48837681. Registered 05 September 2012 - Retrospectively registered. Electronic supplementary material The online version of this article (10.1186/s13071-018-3136-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Stefanie Knopp
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland. .,University of Basel, Petersplatz 1, 4001, Basel, Switzerland. .,Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK.
| | - Shaali M Ame
- Public Health Laboratory Ivo-de Carneri, P.O. Box 122, Chake-Chake, Pemba, United Republic of Tanzania
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Said M Ali
- Public Health Laboratory Ivo-de Carneri, P.O. Box 122, Chake-Chake, Pemba, United Republic of Tanzania
| | - Iddi S Khamis
- Neglected Diseases Programme, Ministry of Health, P.O. Box 236, Unguja, United Republic of Tanzania
| | - Faki Bakar
- Public Health Laboratory Ivo-de Carneri, P.O. Box 122, Chake-Chake, Pemba, United Republic of Tanzania
| | - Mwanaidi A Khamis
- Neglected Diseases Programme, Ministry of Health, P.O. Box 236, Unguja, United Republic of Tanzania
| | - Bobbie Person
- Schistosomiasis Consortium for Operational Research and Evaluation, 145 Coverdell Center, The University of Georgia, 500 D.W. Brooks Drive, Athens, Georgia, 30602, USA
| | - Fatma Kabole
- Neglected Diseases Programme, Ministry of Health, P.O. Box 236, Unguja, United Republic of Tanzania
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
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19
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When Should the Emphasis on Schistosomiasis Control Move to Elimination? Trop Med Infect Dis 2018; 3:tropicalmed3030085. [PMID: 30274481 PMCID: PMC6161309 DOI: 10.3390/tropicalmed3030085] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/04/2018] [Accepted: 08/10/2018] [Indexed: 01/19/2023] Open
Abstract
The stated goal of the World Health Organization’s program on schistosomiasis is paraphrased as follows: to control morbidity and eliminate transmission where feasible. Switching from a goal of controlling morbidity to interrupting transmission may well be currently feasible in some countries in the Caribbean, some areas in South America, northern Africa, and selected endemic areas in sub-Saharan Africa where there have been improvements in sanitation and access to clean water. However, in most of sub-Saharan Africa, where programmatic interventions still consist solely of annual mass drug administration, such a switch in strategies remains premature. There is a continued need for operational research on how best to reduce transmission to a point where interruption of transmission may be achievable. The level of infection at which it is feasible to transition from control to elimination must also be defined. In parallel, there is also a need to develop and evaluate approaches for achieving and validating elimination. There are currently neither evidence-based methods nor tools for breaking transmission or verifying that it has been accomplished. The basis for these statements stems from numerous studies that will be reviewed and summarized in this article; many, but not all of which were undertaken as part of SCORE, the Schistosomiasis Consortium for Operational Research and Evaluation.
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20
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Abudho BO, Ndombi EM, Guya B, Carter JM, Riner DK, Kittur N, Karanja DMS, Secor WE, Colley DG. Impact of Four Years of Annual Mass Drug Administration on Prevalence and Intensity of Schistosomiasis among Primary and High School Children in Western Kenya: A Repeated Cross-Sectional Study. Am J Trop Med Hyg 2018. [PMID: 29532768 PMCID: PMC5953387 DOI: 10.4269/ajtmh.17-0908] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Schistosomiasis remains a major public health problem in Kenya. The World Health Organization recommends preventive chemotherapy with praziquantel (PZQ) to control morbidity due to schistosomiasis. Morbidity is considered linked to intensity of infection, which along with prevalence is used to determine the frequency of mass drug administration (MDA) to school-age children. We determined the impact of annual school-based MDA on children across all primary and high school years using a repeated cross-sectional study design in five schools near Lake Victoria in western Kenya, an area endemic for Schistosoma mansoni. At baseline and for the following four consecutive years, between 897 and 1,440 school children in Grades 1-12 were enrolled and evaluated by Kato-Katz for S. mansoni and soil-transmitted helminths (STH), followed by annual MDA with PZQ and albendazole. Four annual rounds of MDA with PZQ were associated with reduced S. mansoni prevalence in all school children (44.7-14.0%; P < 0.001) and mean intensity of infection by 91% (90.4 to 8.1 eggs per gram [epg] of stool; P < 0.001). Prevalence of high-intensity infection (≥ 400 epg) decreased from 6.8% at baseline to 0.3% by the end of the study. Soil-transmitted helminth infections, already low at baseline, also decreased significantly over the years. In this high prevalence area, annual school-based MDA with high coverage across all Grades (1-12) resulted in rapid and progressive declines in overall prevalence and intensity of infection. This decrease was dramatic in regard to heavy infections in older school-attending children.
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Affiliation(s)
- Bernard O Abudho
- Department of Biomedical Sciences, School of Public Health, Maseno University, Maseno, Kenya.,Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Eric M Ndombi
- Department of Pathology, Kenyatta University, Nairobi, Kenya.,Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Bernard Guya
- Department of Biomedical Sciences, School of Public Health, Maseno University, Maseno, Kenya
| | - Jennifer M Carter
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Diana K Riner
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Nupur Kittur
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Diana M S Karanja
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - W Evan Secor
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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