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da Costa JMC, Gouveia MJ, Rinaldi G, Brindley PJ, Santos J, Santos LL. Control Strategies for Carcinogenic-Associated Helminthiases: An Integrated Overview. Front Cell Infect Microbiol 2021; 11:626672. [PMID: 33842386 PMCID: PMC8025785 DOI: 10.3389/fcimb.2021.626672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 02/26/2021] [Indexed: 12/20/2022] Open
Abstract
Helminthiases are extremely prevalent in the developing world. In addition, the chronic infection with some parasitic worms are classified as carcinogenic. Therefore, it is utmost importance to understand the parasite-host interactions, the mechanisms underlay carcinogenesis and how they could be counteracted. This knowledge may ultimately guide novel control strategies that include chemotherapy-based approaches targeting these pathogens and associated pathologies caused by their infections. Little is known on how some helminthiases are associated with cancer; however, it has been hypothesized that chemical carcinogenesis may be involved in the process. Here, we summarize the current knowledge on chemical carcinogenesis associated with helminthiases, along with available therapeutic options and potential therapeutic alternatives including chemotherapy and/or immunotherapy. Ideally, the treatment of the carcinogenic helminthiases should target both the parasite and associated pathologies. The success of any chemotherapeutic regimen often depends on the host immune response during the infection and nutritional status among other factors. The close association between chemotherapy and cell-mediated immunity suggests that a dual therapeutic approach would be advantageous. In addition, there is a pressing need for complementary drugs that antagonize the carcinogenesis process associated with the helminth infections.
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Affiliation(s)
- José Manuel Correia da Costa
- Centre for the Study in Animal Science (CECA/ICETA), University of Porto, Porto, Portugal
- Centre for Parasite Immunology and Biology, Department of Infectious Diseases, National Institute for Health Dr Ricardo Jorge, Porto, Portugal
| | - Maria João Gouveia
- Centre for the Study in Animal Science (CECA/ICETA), University of Porto, Porto, Portugal
- Centre for Parasite Immunology and Biology, Department of Infectious Diseases, National Institute for Health Dr Ricardo Jorge, Porto, Portugal
- REQUIMTE, Department of Chemical Sciences, Laboratory of Bromatology and Hydrology, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | | | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, and Research Centre for Neglected Diseases of Poverty, School of Medicine & Health Sciences, George Washington University, Washington, DC, United States
| | - Júlio Santos
- Deparment of Urology, Clínica da Sagrada Esperança, Luanda, Angola
| | - Lúcio Lara Santos
- Experimental Pathology and Therapeutics Group, Research Center of Instituto Português de Oncologia, Porto, Portugal
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Kretchy JP, Dzodzomenyo M, Ayi I, Dwomoh D, Agyabeng K, Konradsen F, Dalsgaard A. The Incidence, Intensity, and Risk Factors for Soil Transmissible Helminthes Infections among Waste Handlers in a Large Coastal Periurban Settlement in Southern Ghana. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2021; 2021:5205793. [PMID: 33777151 PMCID: PMC7949191 DOI: 10.1155/2021/5205793] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 01/15/2021] [Accepted: 02/04/2021] [Indexed: 11/18/2022]
Abstract
Soil-transmissible helminthes (STH) infections are among the most common sanitation-related public health problems in poor periurban settlements of tropical regions of low- and middle-income countries. In Ghana, research studies documenting the incidence rate, intensity, and occupational risk factors of STH infections among adults are scanty. A prospective cohort study of 261 waste handlers was conducted to investigate this. Stool samples were collected after 90 and 180 days of treatment with albendazole (400 mg per dose). The geometric mean intensity of STH among waste handlers after 180 days of treatment was 2.8 eggs/gram (light intensity), with an incidence rate of 1.5%. The proportion of waste handlers with light intensity STH infections was 4.8%. The odds of STH infection among female waste handlers were 80% lower when compared with male waste handlers (aOR = 0.2; 95% CI: 0.0-0.8). Waste handlers who used rubber gloves when working were 80% (aOR = 0.2: 95% CI: 0.2-1.9) protected from STH infections compared with those who did not use gloves. Infections with STH among the 261 waste handlers significantly correlated with the type of waste handling activities (LR χ 2 = 15.3; p=0.033) with the highest proportion of infection found among transporters, 2 (40%). Waste handlers should receive periodic antihelminthic treatment, at least once every six months, practice adequate hand hygiene, and use suitable personal protective equipment during work.
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Affiliation(s)
- James-Paul Kretchy
- Department of Physician Assistantship Studies, School of Medicine and Health Sciences, Central University, Miotso, Accra, Ghana
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Mawuli Dzodzomenyo
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Irene Ayi
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Duah Dwomoh
- Department of Biostatistics, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Kofi Agyabeng
- Department of Biostatistics, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Flemming Konradsen
- Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anders Dalsgaard
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore
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Asfaw MA, Wegayehu T, Gezmu T, Bekele A, Hailemariam Z, Gebre T. Determinants of soil-transmitted helminth infections among pre-school-aged children in Gamo Gofa zone, Southern Ethiopia: A case-control study. PLoS One 2020; 15:e0243836. [PMID: 33306738 PMCID: PMC7732061 DOI: 10.1371/journal.pone.0243836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 11/26/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Pre-school aged children (PSAC) are highly affected by soil-transmitted helminths (STH), particularly in areas where water, sanitation, and hygiene (WASH) are inadequate. Context-specific evidence on determinants of STH infections in PSAC has not been well established in the study area. This study, therefore, aimed to fill these gaps in Gamo Gofa zone, Southern Ethiopia. METHODS A community-based unmatched case-control study, nested in a cross-sectional survey, was conducted in January 2019. Cases and controls were identified based on any STH infection status using the Kato-Katz technique in stool sample examination. Data on social, demographic, economic, behavioral, and WASH related variables were collected from primary caregivers of children using pre-tested questionnaire. Determinants of STH infections were identified using multivariable logistic regression model using SPSS version 25. RESULTS A total of 1206 PSAC (402 cases and 804 controls) participated in this study. Our study showed that the odds of STH infection were lowest among PSAC living in urban areas (AOR = 0.55, 95% CI: 0.39-0.79), among those from households with safe water source (AOR = 0.67, 95% CI: 0.47-0.0.93), and in those PSAC from households with shorter distance from water source (<30 minutes) (AOR = 0.51, 95% CI: 0.39-0.67). On the other hand, the odds of STH infection were highest among PSAC from households that had no functional hand washing facility (AOR = 1.36, 95% CI: 1.04-1.77), in those PSAC from households that had unclean latrine (AOR: 1.82, 95% CI: 1.19-2.78), and among those PSAC under caregivers who had lower score (≤5) on knowledge related to STH transmission (AOR = 1.85, 95% CI: 1.13-3.01). CONCLUSIONS Given efforts required eliminating STH by 2030; the existing preventive chemotherapy intervention should be substantially strengthened with WASH and behavioral interventions. Thus, an urgent call for action is required to integrate context-specific interventions, particularly in rural areas.
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Affiliation(s)
- Mekuria Asnakew Asfaw
- Collaborative Research and Training Centre for NTDs, Arba Minch University, Arba Minch, Ethiopia
| | - Teklu Wegayehu
- Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Tigist Gezmu
- Collaborative Research and Training Centre for NTDs, Arba Minch University, Arba Minch, Ethiopia
| | - Alemayehu Bekele
- Collaborative Research and Training Centre for NTDs, Arba Minch University, Arba Minch, Ethiopia
| | - Zeleke Hailemariam
- School of Public Health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Teshome Gebre
- The Task Force for Global Health, International Trachoma Initiative, Addis Ababa, Ethiopia
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Abe EM, Tambo E, Xue J, Xu J, Ekpo UF, Rollinson D, Yang K, Li SZ, Zhou XN. Approaches in scaling up schistosomiasis intervention towards transmission elimination in Africa: Leveraging from the Chinese experience and lessons. Acta Trop 2020; 208:105379. [PMID: 32006521 DOI: 10.1016/j.actatropica.2020.105379] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 01/29/2020] [Accepted: 01/29/2020] [Indexed: 12/20/2022]
Abstract
Schistosoma japonicum, differs from the African species including S. mansoni and S. haematobium, is a zoonotic parasite as it infects both human and animals including domestic ruminant animals such as cattle and animals from the wild. Considering China's success story in the elimination of schistosomiasis, the China-Africa collaboration on schistosomaisis elimination in Africa is an important cooperative health development initiative. This review examines the importance of China-Africa collaboration on schistosomiasis elimination using effective surveillance-response intervention strategy as the platform to effectively drive the elimination of schistosomiasis in Africa. Three conclusions were made after reviewing the similarity and differences in schistososmiasis control programmes between China and African continent as follows: (i) Politically, China's lessons is that leveraging on the integrated control strategies and the recognition that schistosomiasis is a public health problem which prompted the interest of government in China. It is necessary for African leaders and governments to recognize schistosomiasis as a public health challenge that must be given serious attention in terms of funding and setting up frameworks to complement control efforts. (ii) Technically, efficient monitoring and surveillance system mechanism will facilitate contextual and effective management of schistosomiasis elimination across different environment, and African programme managers should embrace the use of appropriate diagnostic tools to guide treatment strategies at different thresholds of schistosomiasis control. (iii) Strategically, effective control of snail intermediate hosts and precision mapping of snail distribution should be prioritized for successful schistosomiasis elimination in Africa.
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Affiliation(s)
- Eniola M Abe
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
| | - E Tambo
- Département de Biochimie et Science Pharmaceutiques, Université des Montagnes, Bagangté, République du Cameroon.
| | - Jingbo Xue
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
| | - Jing Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
| | - Uwem F Ekpo
- Department of Pure and Applied Zoology, Federal University of Agriculture, Alabata Road, Abeokuta, 110001, Nigeria.
| | - David Rollinson
- The Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom.
| | - Kun Yang
- Jiangsu Institute of Parasitic Diseases, Wuxi, China.
| | - Shi-Zhu Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
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Odeniran PO, Omolabi KF, Ademola IO. Epidemiological dynamics and associated risk factors of S. haematobium in humans and its snail vectors in Nigeria: a meta-analysis (1983-2018). Pathog Glob Health 2020; 114:76-90. [PMID: 32182201 DOI: 10.1080/20477724.2020.1728164] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Schistosoma haematobium, a major pathogen of urogenital schistosomiasis, has been reported to be affecting an estimated 30 million people in Nigeria. Current national estimates of S. haematobium and its cercariae, in humans and snail vectors respectively, are lacking in Nigeria, hence systematic meta-analyses were conducted to understand the disease dynamics in the endemic country over a period of 35 years based on publications from five databases (AJOL, Ovid MEDLINE, Google Scholar, PubMed and Web of Science). The preferred reporting items for systematic reviews and meta-analyses (PRIMSA) checklist were used as the standard guide for the analyses. The prevalence of S. haematobium in human hosts in Nigeria using quality effects model was 32.1% (27.3-37.2), while schistosome cercariae were observed at 3.5% (0.0-11.9), 18.2% (4.7-36.8) and 18.7% (0.0-46.1) and for B. forskalii, Bulinus globosus and B. truncatus, respectively. The high report of schistosome cercariae indicates the continuous transmission of S. haematobium in humans especially with individuals who have frequent contact with freshwater. Heterogeneity of subgroup analyses (regions, zones, sex, age groups, diagnostic techniques) and risk factors (pathological signs, occupation, water sources, anthropogenic activities, treatment) were determined. The result showed prevalence of an endemic moderate class infection that has been linked to several risk factors. Therefore, there is need for increased awareness on the prevalence, transmission routes and treatment strategies to mitigate the disease in this endemic area.
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Affiliation(s)
- Paul Olalekan Odeniran
- Department of Veterinary Parasitology and Entomology, University of Ibadan, Ibadan, Nigeria
| | - Kehinde Foluke Omolabi
- Molecular Bio-computation and Drug Design Laboratory, University of KwaZulu Natal, Durban, South Africa
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Mulopo C, Kalinda C, Chimbari MJ. Contextual and Psychosocial Factors Influencing the Use of Safe Water Sources: A Case of Madeya Village, uMkhanyakude District, South Africa. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17041349. [PMID: 32093109 PMCID: PMC7068542 DOI: 10.3390/ijerph17041349] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/11/2020] [Accepted: 02/12/2020] [Indexed: 12/14/2022]
Abstract
Background: Schistosomiasis is a public health problem that affects over 240 million people worldwide. It is mostly prevalent in tropical and sub-tropical areas among communities with limited access to clean water and adequate sanitation. This study was conducted in uMkhanyakude District in rural South Africa, where water resources are limited. In this community, individuals frequently come into contact with freshwater bodies for various reasons. The objective of the study was to identify critical contextual and psychosocial factors for behaviour change to reduce risk of schistosomiasis transmission in Madeya Village, uMkhanyakude district. Methods: Structured household interviews were held with 57 primary caregivers to assess their thoughts and attitudes towards collecting water from a safe source. We used the Risk, Attitude, Norm, Ability, and Self-regulation model (RANAS) to estimate the intervention potential for each factor by analysing differences in means between groups of current performers and nonperformers who use safe water sources. Results: The subscale vulnerability belonging to the risk factor on the RANAS was scored as low. Furthermore, attitudinal factors towards the use of safe water sources were found to be low. Ability factors (confidence in performance and confidence in recovery) towards the use of safe water sources were low as well, indicating that these factors should be the target of the intervention in the study area. Discussion: Based on this study, it is recommended that a community-based empowerment intervention strategy it appropriate. The strategy should prompt behavioural practice and public commitment, use persuasive language to boost self-efficacy and target younger low-income caregivers between 18 and 35 years of age.
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Affiliation(s)
- Chanelle Mulopo
- School of Nursing and Public Health, College of Health Sciences, University of KwaZulu-Natal, Howard Campus, Durban 4001, South Africa;
- Correspondence:
| | - Chester Kalinda
- School of Nursing and Public Health, College of Health Sciences, University of KwaZulu-Natal, Howard Campus, Durban 4001, South Africa;
- Faculty of Agriculture and Natural resources, University of Namibia, Katima Mulilo Campus, Winela Road, Box 1096, Ngweze, Katima Mulilo, Namibia
| | - Moses J. Chimbari
- School of Nursing and Public Health, College of Health sciences, University of KwaZulu-Natal, Howard Campus, Durban 4001, South Africa;
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Saelens G, Gabriël S. Currently Available Monitoring and Surveillance Systems for Taenia spp., Echinococcus spp., Schistosoma spp., and Soil-Transmitted Helminths at the Control/Elimination Stage: A Systematic Review. Pathogens 2020; 9:E47. [PMID: 31935916 PMCID: PMC7168685 DOI: 10.3390/pathogens9010047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/02/2020] [Accepted: 01/02/2020] [Indexed: 12/13/2022] Open
Abstract
An increasing global focus on neglected tropical diseases (NTDs) has resulted in the set up of numerous control and elimination activities worldwide. This is partly true for Taenia solium taeniasis/cysticercosis, the most important foodborne parasitic infection. Despite substantial progress, adequate monitoring and surveillance (M&S) are required to sustain a status of control/elimination. This is often lacking, especially for T. solium. Therefore, the objective was to conduct a systematic literature review of the currently available M&S systems at the control/elimination stage of the four top-ranked helminth NTDs. Specifically, Taenia spp., Echinococcus spp., Schistosoma spp., and soil-transmitted helminths (STHs) were considered to determine if there are any similarities between their M&S systems and whether certain approaches can be adopted from each other. The systematic review demonstrated that rigorous M&S systems have been designed for the control/elimination stage of both STHs and schistosomiasis, particularly in China. On the other hand, a concept of M&S for Taenia spp. and Echinococcus spp. has not been fully developed yet, due to a lack of epidemiological data and the fact that many endemic countries are far away from reaching control/elimination. Moreover, accurate diagnostic tools for all four diseases are still imperfect, which complicates proper M&S. Finally, there is an urgent need to develop and harmonize/standardize M&S activities in order to reliably determine and compare the epidemiological situation worldwide.
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Affiliation(s)
- Ganna Saelens
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke B-9820, Belgium
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Bizimana P, Ortu G, Van Geertruyden JP, Nsabiyumva F, Nkeshimana A, Muhimpundu E, Polman K. Integration of schistosomiasis control activities within the primary health care system: a critical review. Parasit Vectors 2019; 12:393. [PMID: 31391100 PMCID: PMC6686413 DOI: 10.1186/s13071-019-3652-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 08/01/2019] [Indexed: 01/11/2023] Open
Abstract
Background Schistosomiasis is a chronic disease linked to poverty and is widely endemic, particularly in sub-Saharan Africa. For decades, the World Health Organization has called for a larger role of the primary health care system in schistosomiasis control, and its integration within the routine activities of primary health care facilities. Here, we reviewed existing studies on the integration of schistosomiasis control measures within the primary health care system, more precisely at the health centre, and we analysed their outcomes. Methods An online search of studies published via PubMed and Embase databases was carried out until December 2017. Keywords were used to identify articles related to the integration of schistosomiasis control within the primary health care system, especially at the health centre level. Studies on integration of the following control measures were included: diagnosis and treatment, supplemented or not with (i) health education; (ii) snail control; and (iii) clean water supply and sanitation. A qualitative review was undertaken. To conclude on the effectiveness of an intervention, intermediate outcomes (knowledge, attitude and practice, coverage, access to health care) and distal outcomes (prevalence, incidence, mortality) were considered, and pre/post-intervention results were compared. Results Of 569 records found, 11 met the inclusion criteria. Studies were classified in three groups, according to the control measures they included. Integration of diagnosis and treatment, and health education in the first group resulted in an improvement of knowledge level of care providers, access to health care and health care seeking behaviour of the community. However, no positive effect was observed on the knowledge level of symptoms and modes of transmission at the community level. Most studies in the second group (with snail control as additional measure) and the third group (with clean water supply and sanitation as additional measure) showed a positive effect on schistosomiasis prevalence and incidence post-intervention, independent of the additional control measures implemented. Conclusions The results of this review suggest a positive impact of integration of schistosomiasis control within the primary health care system. However, more robust studies are needed, especially in resource-limited regions, for conclusive evidence on the effectiveness and the sustainability of this strategy.
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Affiliation(s)
- Paul Bizimana
- Global Health Institute, Department of Epidemiology and Social Medicine, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. .,Département des Sciences de la Santé Publique, Direction de la Formation, Institut National de Santé Publique, Bujumbura, Burundi. .,Département de Médecine Communautaire, Faculté de Médecine de Bujumbura, Université du Burundi, Bujumbura, Burundi. .,Département des Sciences de la Santé Publique, Institut Universitaire des Sciences de la Santé et de Développement Communautaire, Bujumbura, Burundi.
| | - Giuseppina Ortu
- Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Jean-Pierre Van Geertruyden
- Global Health Institute, Department of Epidemiology and Social Medicine, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Frédéric Nsabiyumva
- Département de Médecine Interne, Faculté de Médecine de Bujumbura, Université du Burundi, Bujumbura, Burundi
| | - Audace Nkeshimana
- Département des Sciences de la Santé Publique, Direction de la Formation, Institut National de Santé Publique, Bujumbura, Burundi.,Département des Sciences de la Santé Publique, Institut Universitaire des Sciences de la Santé et de Développement Communautaire, Bujumbura, Burundi
| | - Elvis Muhimpundu
- Programme National Intégré de Lutte contre les Maladies Tropicales Négligées et la Cécité, Département des programmes de santé, Ministère de la Santé Publique et de la Lutte contre le Sida, Bujumbura, Burundi
| | - Katja Polman
- Medical Helminthology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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A bioassay-based protocol for chemical neutralization of human faecal wastes treated by physico-chemical disinfection processes: A case study on benzalkonium chloride. Int J Hyg Environ Health 2018; 222:155-167. [PMID: 30424942 PMCID: PMC7172796 DOI: 10.1016/j.ijheh.2018.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/28/2018] [Accepted: 07/03/2018] [Indexed: 11/21/2022]
Abstract
In situ physico-chemical disinfection of high risk faecal waste is both effective and widely used as a sanitation management strategy for infection prevention and control. Systematic tests where the performance of alternative physico-chemical disinfection methods is systematically compared and optimized must be based on reliable protocols. These protocol are currently not adequately addressing the neutralization related issues: the neutralization of the tested disinfectant after specified conditions of concentration and contact time (CT) is necessary to prevent continued disinfection after the intended contact time; moreover such neutralization is often necessary in practice and on a large scale to prevent adverse health and ecological impacts from remaining disinfectant after the target CT is achieved. Few studies adequately assess the extent of neutralization of the chemical disinfectant and are intended to optimize on-site disinfection practices for waste matrices posing high microbial risks. Hence, there is a need for effective and reproducible neutralization protocols in chemical disinfection trials and practice. Furthermore, for most of chemical disinfectants used in healthcare settings there is no practical methodology to reliably and conveniently measure the residual disinfectant concentration after its neutralization and also determine the optimum concentration of the neutralizer. Because some neutralizing compounds can themselves be toxic to the test microorganisms, it is necessary to optimize neutralization procedures in disinfection experiments for the development of infection control practices using accepted positive control microbes. In the presented work, a stepwise bioassay-based protocol using representative faecal indicator microbes is described for optimizing chemical disinfection and subsequent disinfectant neutralization of any infectious faecal waste matrix. The example described is for the quaternary ammonium compound benzalkonium chloride and its recommended chemical neutralizer in a high strength human faecal waste matrix.
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M'Bra RK, Kone B, Yapi YG, Silué KD, Sy I, Vienneau D, Soro N, Cissé G, Utzinger J. Risk factors for schistosomiasis in an urban area in northern Côte d'Ivoire. Infect Dis Poverty 2018; 7:47. [PMID: 29773076 PMCID: PMC5958400 DOI: 10.1186/s40249-018-0431-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 04/19/2018] [Indexed: 11/25/2022] Open
Abstract
Background Schistosomiasis is a water-based disease transmitted by trematodes belonging to the genus Schistosoma. The aim of this study was to assess the relationship between the prevalence of schistosomiasis and access to water, sanitation and hygiene (WASH) and environmental and socioeconomic factors in the city of Korhogo, northern Côte d'Ivoire. Methods A cross-sectional study including 728 randomly selected households was conducted in Korhogo in March 2015. The heads of the households were interviewed about access to WASH and environmental and socioeconomic factors. All children abed between 5 and 15 years living in the households were selected to provide stool and urine samples for parasitological diagnosis of Schistosoma mansoni and Schistosoma haematobium infection. The relationship between infection with S. mansoni and potential risk factors was analysed by a mixed logistic regression model with ‘household’ as a random factor. Likelihood ratio tests were used to identify factors that were significantly associated with a Schistosoma spp. infection. Results The overall prevalence of schistosomiasis among school-aged children in Korhogo was 1.9% (45/2341) composed of 0.3% (3/1248) S. haematobium and 3.5% (42/1202) S. mansoni. Due to the low prevalence of S. haematobium infection, risk factor analysis was limited to S. mansoni. Boys were 7.8 times more likely to be infected with S. mansoni than girls. Children between 10 and 15 years of age were 3.8 times more likely to be infected than their younger counterparts aged 5-10 years. Moreover, living in a house further away from a water access point (odds ratio [OR] = 0.29, 95% confidence interval [CI]: 0.13–0.70) and abstaining from swimming in open freshwater bodies (OR = 0.16, 95% CI: 0.04–0.56) were significantly associated with decreased odds of S. mansoni infection. The socioeconomic status did not appear to influence the prevalence of S. mansoni. Conclusions A strategy to reduce the incidence of schistosomiasis should focus on health education to change the behaviour of populations at risk and encourage communities to improve sanitation and infrastructure in order to reduce contact with surface water. Electronic supplementary material The online version of this article (10.1186/s40249-018-0431-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard K M'Bra
- Unité de Formation et de Recherche des Sciences de la Terre et des Ressources Minières, Université Félix Houphouët-Boigny, 01 BP V 34,, Abidjan 01, Côte d'Ivoire. .,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, 01 BP 1303,, Abidjan 01, Côte d'Ivoire. .,Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland. .,University of Basel, P.O. Box, CH-4003, Basel, Switzerland.
| | - Brama Kone
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, 01 BP 1303,, Abidjan 01, Côte d'Ivoire.,Institut de Gestion Agropastorale, Université Péléforo Gon Coulibaly, BP 1328,, Korhogo, Côte d'Ivoire
| | - Yapi G Yapi
- Centre d'Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, 27 BP 529,, Abidjan 27, Côte d'Ivoire
| | - Kigbafori D Silué
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, 01 BP 1303,, Abidjan 01, Côte d'Ivoire.,Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, 22 BP 522,, Abidjan 22, Côte d'Ivoire
| | - Ibrahima Sy
- Centre de Suivi Ecologique, BP 15 532,, Dakar, Senegal
| | - Danielle Vienneau
- Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland.,University of Basel, P.O. Box, CH-4003, Basel, Switzerland
| | - Nagnin Soro
- Unité de Formation et de Recherche des Sciences de la Terre et des Ressources Minières, Université Félix Houphouët-Boigny, 01 BP V 34,, Abidjan 01, Côte d'Ivoire
| | - Guéladio Cissé
- Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland.,University of Basel, P.O. Box, CH-4003, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland.,University of Basel, P.O. Box, CH-4003, Basel, Switzerland
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11
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Bardosh KL, Ryan SJ, Ebi K, Welburn S, Singer B. Addressing vulnerability, building resilience: community-based adaptation to vector-borne diseases in the context of global change. Infect Dis Poverty 2017; 6:166. [PMID: 29228986 PMCID: PMC5725972 DOI: 10.1186/s40249-017-0375-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 11/15/2017] [Indexed: 11/14/2022] Open
Abstract
Background The threat of a rapidly changing planet – of coupled social, environmental and climatic change – pose new conceptual and practical challenges in responding to vector-borne diseases. These include non-linear and uncertain spatial-temporal change dynamics associated with climate, animals, land, water, food, settlement, conflict, ecology and human socio-cultural, economic and political-institutional systems. To date, research efforts have been dominated by disease modeling, which has provided limited practical advice to policymakers and practitioners in developing policies and programmes on the ground. Main body In this paper, we provide an alternative biosocial perspective grounded in social science insights, drawing upon concepts of vulnerability, resilience, participation and community-based adaptation. Our analysis was informed by a realist review (provided in the Additional file 2) focused on seven major climate-sensitive vector-borne diseases: malaria, schistosomiasis, dengue, leishmaniasis, sleeping sickness, chagas disease, and rift valley fever. Here, we situate our analysis of existing community-based interventions within the context of global change processes and the wider social science literature. We identify and discuss best practices and conceptual principles that should guide future community-based efforts to mitigate human vulnerability to vector-borne diseases. We argue that more focused attention and investments are needed in meaningful public participation, appropriate technologies, the strengthening of health systems, sustainable development, wider institutional changes and attention to the social determinants of health, including the drivers of co-infection. Conclusion In order to respond effectively to uncertain future scenarios for vector-borne disease in a changing world, more attention needs to be given to building resilient and equitable systems in the present. Electronic supplementary material The online version of this article (doi: 10.1186/s40249-017-0375-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kevin Louis Bardosh
- Department of Anthropology, University of Florida, Gainesville, USA. .,Emerging Pathogens Institute, University of Florida, Gainesville, USA.
| | - Sadie J Ryan
- Emerging Pathogens Institute, University of Florida, Gainesville, USA.,Department of Geography, University of Florida, Gainesville, USA
| | - Kris Ebi
- Department of Global Health, University of Washington, Seattle, USA
| | - Susan Welburn
- Centre of Infectious Disease, University of Edinburgh, Edinburgh, UK
| | - Burton Singer
- Emerging Pathogens Institute, University of Florida, Gainesville, USA
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12
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Simoonga C, Kazembe LN. Using the hierarchical ordinal regression model to analyse the intensity of urinary schistosomiasis infection in school children in Lusaka Province, Zambia. Infect Dis Poverty 2017; 6:43. [PMID: 28219411 PMCID: PMC5319044 DOI: 10.1186/s40249-017-0262-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/16/2017] [Indexed: 12/19/2022] Open
Abstract
Background Urinary schistosomiasis has been a major public health problem in Zambia for many years. However, the disease profile may vary in different locale due to the changing ecosystem that contributes to the risk of acquiring the disease. The objective of this study was to quantify risk factors associated with the intensity of urinary schistosomiasis infection in school children in Lusaka Province, Zambia, in order to better understand local transmission. Methods Data were obtained from 1 912 school children, in 20 communities, in the districts of Luangwa and Kafue in Lusaka Province. Both individual- and community-level covariates were incorporated into an ordinal logistic regression model to predict the probability of an infection being a certain intensity in a three-category outcome response: 0 = no infection, 1 = light infection, and 2 = moderate/heavy infection. Random effects were introduced to capture unobserved heterogeneity. Results Overall, the risk of urinary schistosomiasis was strongly associated with age, altitude at which the child lived, and sex. Weak associations were observed with the normalized difference vegetation index, maximum temperature, and snail abundance. Detailed analysis indicated that the association between infection intensities and age and altitude were category-specific. Particularly, infection intensity was lower in children aged between 5 and 9 years compared to those aged 10 to 15 years (OR = 0.72, 95% CI = 0.51–0.99). However, the age-specific risk changed at different levels of infection, such that when comparing children with light infection to those who were not infected, age was associated with a lower odds (category 1 vs category 0: OR = 0.71, 95% CI: 0.50–0.99), yet such a relation was not significant when considering children who were moderately or heavily infected compared to those with a light or no infection (category 2 vs category 0: OR = 0.96, 95% CI: 0.45–1.64). Overall, we observed that children living in the valley were less likely to acquire urinary schistosomiasis compared to those living in plateau areas (OR = 0.48, 95% CI: 0.16–0.71). However, category-specific effects showed no significant association in category 1 (light infection), whereas in category 2 (moderate/high infection), the risk was still significantly lower for those living in the valley compared to those living in plateau areas (OR = 0.18, 95% CI: 0.04–0.75). Conclusions This study demonstrates the importance of understanding the dynamics and heterogeneity of infection in control efforts, and further suggests that apart from the well-researched factors of Schistosoma intensity, various other factors influence transmission. Control programmes need to take into consideration the varying infection intensities of the disease so that effective interventions can be designed. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0262-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christopher Simoonga
- Ministry of Health, Ndeke House, Haile Selassie Avenue, P.O. Box 30205, Lusaka, Zambia
| | - Lawrence N Kazembe
- Mathematical Sciences Department, Chancellor College, University of Malawi, P.O. Box 280, Zomba, Malawi. .,Statistics and Population Studies Department, University of Namibia, Private Bag 13301, Windhoek, Namibia.
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13
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Mapping Soil Transmitted Helminths and Schistosomiasis under Uncertainty: A Systematic Review and Critical Appraisal of Evidence. PLoS Negl Trop Dis 2016; 10:e0005208. [PMID: 28005901 PMCID: PMC5179027 DOI: 10.1371/journal.pntd.0005208] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/23/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Spatial modelling of STH and schistosomiasis epidemiology is now commonplace. Spatial epidemiological studies help inform decisions regarding the number of people at risk as well as the geographic areas that need to be targeted with mass drug administration; however, limited attention has been given to propagated uncertainties, their interpretation, and consequences for the mapped values. Using currently published literature on the spatial epidemiology of helminth infections we identified: (1) the main uncertainty sources, their definition and quantification and (2) how uncertainty is informative for STH programme managers and scientists working in this domain. METHODOLOGY/PRINCIPAL FINDINGS We performed a systematic literature search using the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) protocol. We searched Web of Knowledge and PubMed using a combination of uncertainty, geographic and disease terms. A total of 73 papers fulfilled the inclusion criteria for the systematic review. Only 9% of the studies did not address any element of uncertainty, while 91% of studies quantified uncertainty in the predicted morbidity indicators and 23% of studies mapped it. In addition, 57% of the studies quantified uncertainty in the regression coefficients but only 7% incorporated it in the regression response variable (morbidity indicator). Fifty percent of the studies discussed uncertainty in the covariates but did not quantify it. Uncertainty was mostly defined as precision, and quantified using credible intervals by means of Bayesian approaches. CONCLUSION/SIGNIFICANCE None of the studies considered adequately all sources of uncertainties. We highlighted the need for uncertainty in the morbidity indicator and predictor variable to be incorporated into the modelling framework. Study design and spatial support require further attention and uncertainty associated with Earth observation data should be quantified. Finally, more attention should be given to mapping and interpreting uncertainty, since they are relevant to inform decisions regarding the number of people at risk as well as the geographic areas that need to be targeted with mass drug administration.
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14
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Assaré RK, Tian-Bi YNT, Yao PK, N’Guessan NA, Ouattara M, Yapi A, Coulibaly JT, Meïté A, Hürlimann E, Knopp S, Utzinger J, N’Goran EK. Sustaining Control of Schistosomiasis Mansoni in Western Côte d'Ivoire: Results from a SCORE Study, One Year after Initial Praziquantel Administration. PLoS Negl Trop Dis 2016; 10:e0004329. [PMID: 26789749 PMCID: PMC4720284 DOI: 10.1371/journal.pntd.0004329] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 12/04/2015] [Indexed: 12/23/2022] Open
Abstract
Background The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has launched several large-scale trials to determine the best strategies for gaining and sustaining control of schistosomiasis and transitioning toward elimination. In Côte d’Ivoire, a 5-year cluster-randomized trial is being implemented in 75 schools to sustain the control of schistosomiasis mansoni. We report Schistosoma mansoni infection levels in children one year after the initial school-based treatment (SBT) with praziquantel and compare with baseline results to determine the effect of the intervention. Methodology The baseline cross-sectional survey was conducted in late 2011/early 2012 and the first follow-up in May 2013. Three consecutive stool samples were collected from 9- to 12-year-old children in 75 schools at baseline and 50 schools at follow-up. Stool samples were subjected to duplicate Kato-Katz thick smears. Directly observed treatment (DOT) coverage of the SBT was assessed and the prevalence and intensity of S. mansoni infection compared between baseline and follow-up. Principal Findings The S. mansoni prevalence in the 75 schools surveyed at baseline was 22.1% (95% confidence interval (CI): 19.5–24.4%). The DOT coverage was 84.2%. In the 50 schools surveyed at baseline and one year after treatment, the overall prevalence of S. mansoni infection decreased significantly from 19.7% (95% CI: 18.5–20.8%) to 12.8% (95% CI: 11.9–13.8%), while the arithmetic mean S. mansoni eggs per gram of stool (EPG) among infected children slightly increased from 92.2 EPG (95% CI: 79.2–105.3 EPG) to 109.3 EPG (95% CI: 82.7–135.9 EPG). In two of the 50 schools, the prevalence increased significantly, despite a DOT coverage of >75%. Conclusions/Significance One year after the initial SBT, the S. mansoni prevalence had decreased. Despite this positive trend, an increase was observed in some schools. Moreover, the infection intensity among S. mansoni-infected children was slightly higher at the 1-year follow-up compared to the baseline situation. Our results emphasize the heterogeneity of transmission dynamics and provide a benchmark for the future yearly follow-up surveys of this multi-year SCORE intervention study. Schistosomiasis is a parasitic worm disease that is widespread in sub-Saharan Africa. To better understand how to gain and sustain the control of schistosomiasis and how to eliminate this disease in different epidemiologic settings, the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has launched several multi-year studies that are being implemented in East and West Africa. This article highlights how the Schistosoma mansoni infection levels changed one year after an initial treatment with the anti-worm drug praziquantel given to children aged 5–15 years in western Côte d’Ivoire. Infection and treatment data at school level were available from more than 4,600 children in 50 schools. One year after the treatment that had been received by more than 80% of the children, the overall S. mansoni prevalence decreased from 19.7% to 12.8%, while the intensity of infection among S. mansoni-positive children slightly increased. In several schools, the S. mansoni intensity and, particularly the prevalence, increased unexpectedly. Our findings show that the dynamics of schistosomiasis transmission varies from one village to another. It will be interesting to monitor changes over longer time periods as this SCORE study unfolds.
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Affiliation(s)
- Rufin K. Assaré
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- 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
| | - Yves-Nathan T. Tian-Bi
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Patrick K. Yao
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Nicaise A. N’Guessan
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Ahoua Yapi
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Jean T. Coulibaly
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- 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
| | - Aboulaye Meïté
- Programme National de Lutte contre la Schistosomiase, les Géohelminthiases et la Filariose Lymphatique, Abidjan, Côte d’Ivoire
| | - Eveline Hürlimann
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| | - 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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15
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Krauth SJ, Musard C, Traoré SI, Zinsstag J, Achi LY, N'Goran EK, Utzinger J. Access to, and use of, water by populations living in a schistosomiasis and fascioliasis co-endemic area of northern Côte d'Ivoire. Acta Trop 2015; 149:179-85. [PMID: 26004285 DOI: 10.1016/j.actatropica.2015.05.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 05/18/2015] [Accepted: 05/20/2015] [Indexed: 12/29/2022]
Abstract
Water is an essential element of life, but it can also be a source of disease. Apart from direct consumption of unsafe water, direct contact and indirect consumption puts people at risk of many different types of pathogens. Employing a mixed methods approach, consisting of questionnaires and direct observations, we assessed access to, and use of, different water sources by the participants of the district des Savanes in northern Côte d'Ivoire. The use of water sources was put in relation to the potential risk of acquiring schistosomiasis and fascioliasis. Overall, 489 people aged 8 to 82 years participated. While all participants had access to safe water, 63% were in direct contact with unimproved water and 31% directly consumed unsafe water. More than a third of the people who otherwise reported using only improved water for all activities came in contact with unimproved water through crossing open water when going to their workplace, school or other destinations. Self-reported blood in urine - a marker for Schistosoma haematobium with reasonable sensitivity and specificity - was reported by 6% (n=30), self-reported blood in stool - an unspecific marker for Schistosoma mansoni - was reported by 7% (n=35), while blood co-occurring in both urine and stool was reported by another 10% (n=48) of participants. Accessing unimproved water for any activity (including crossing) was associated with higher odds of reporting blood in urine and/or blood in stool (odds ratio: 1.90; 95% confidence interval: 1.07-3.36). Our results have important rami-fications for intervention programmes targeting neglected tropical diseases, and emphasize the need for a wider supply of safe water to rural populations, since the water supply at the workplace needs to be considered as well next to the water supply at home. Crossing of open water sources is an important risk factor for sustained transmission of schistosomiasis.
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Affiliation(s)
- Stefanie J Krauth
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Capucine Musard
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire; Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Seïdinan I Traoré
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire; Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire; Laboratoire Regional d'Appui au Développement Agricole de Korhogo, Korhogo, Côte d'Ivoire
| | - Jakob Zinsstag
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Louise Y Achi
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire; Ecole de Spécialisation en Elevage de Bingerville, Bingerville, Côte d'Ivoire
| | - Eliézer K N'Goran
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire; Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
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16
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Masaku J, Madigu N, Okoyo C, Njenga SM. Current status of Schistosoma mansoni and the factors associated with infection two years following mass drug administration programme among primary school children in Mwea irrigation scheme: A cross-sectional study. BMC Public Health 2015; 15:739. [PMID: 26231050 PMCID: PMC4522152 DOI: 10.1186/s12889-015-1991-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 06/29/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Schistosomiasis is a major public health problem in Kenya as well as in many other tropical countries and is considered one of the most prevalent diseases in the rural population. Between 2004 and 2009, primary school children in Mwea irrigation scheme were treated for Schistosoma mansoni. In the four year control programme, there was occurrence of light re-infection with S. mansoni. Therefore, the aim of this study was to assess the current prevalence of S. mansoni, infection two years after the withdrawal of mass drug administration (MDA) programme. METHODS We carried out a cross-sectional study on a population of 387 children attending 3 primary schools located in Mwea irrigation scheme. Children, aged 8-16 years were interviewed and screened for S. mansoni using duplicate Kato-Katz thick smears. Comparisons of prevalence by age group and gender were tested for significance on the basis of the Wald test. Best prediction factors for infection with S. mansoni were selected using forward - stepwise variable selection method. RESULTS The overall prevalence of S. mansoni was 53.7 %, (95%CI: 49.0-59.0, p-value = 0.000). Male children had higher prevalence of infection, 66.1 % (95%CI: 59.8-73.2, p-value = 0.000) compared to females. The gender (sex) of a child was the only factor reported to be significantly associated with S. mansoni infection, (OR = 1.9, p-value = 0.015, 95%CI: 1.13-3.21). CONCLUSIONS There was high prevalence of S. mansoni infections in the study area, two years after the withdrawal of MDA programme. We suggest that treatment should be continued in the school children at regular intervals, monitoring and surveillance intensified to ensure interruption of transmission areas.
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Affiliation(s)
- Janet Masaku
- Esatern and Southern Africa Centre of International Parasite Control (ESACIPAC), Kenya Medical Research Institute (KEMRI), P.O Box 54840 - 00200, Nairobi, Kenya. .,Great Lakes University of Kisumu (GLUK), P.O. Box 60827, 00200, Nairobi, Kenya.
| | - Nancy Madigu
- Great Lakes University of Kisumu (GLUK), P.O. Box 60827, 00200, Nairobi, Kenya.
| | - Collins Okoyo
- Esatern and Southern Africa Centre of International Parasite Control (ESACIPAC), Kenya Medical Research Institute (KEMRI), P.O Box 54840 - 00200, Nairobi, Kenya.
| | - Sammy M Njenga
- Esatern and Southern Africa Centre of International Parasite Control (ESACIPAC), Kenya Medical Research Institute (KEMRI), P.O Box 54840 - 00200, Nairobi, Kenya.
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Minimizing the Risk of Disease Transmission in Emergency Settings: Novel In Situ Physico-Chemical Disinfection of Pathogen-Laden Hospital Wastewaters. PLoS Negl Trop Dis 2015; 9:e0003776. [PMID: 26110821 PMCID: PMC4482504 DOI: 10.1371/journal.pntd.0003776] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 04/21/2015] [Indexed: 01/05/2023] Open
Abstract
The operation of a health care facility, such as a cholera or Ebola treatment center in an emergency setting, results in the production of pathogen-laden wastewaters that may potentially lead to onward transmission of the disease. The research presented here evaluated the design and operation of a novel treatment system, successfully used by Médecins Sans Frontières in Haiti to disinfect CTC wastewaters in situ, eliminating the need for road haulage and disposal of the waste to a poorly-managed hazardous waste facility, thereby providing an effective barrier to disease transmission through a novel but simple sanitary intervention. The physico-chemical protocols eventually successfully treated over 600 m3 of wastewater, achieving coagulation/flocculation and disinfection by exposure to high pH (Protocol A) and low pH (Protocol B) environments, using thermotolerant coliforms as a disinfection efficacy index. In Protocol A, the addition of hydrated lime resulted in wastewater disinfection and coagulation/flocculation of suspended solids. In Protocol B, disinfection was achieved by the addition of hydrochloric acid, followed by pH neutralization and coagulation/flocculation of suspended solids using aluminum sulfate. Removal rates achieved were: COD >99%; suspended solids >90%; turbidity >90% and thermotolerant coliforms >99.9%. The proposed approach is the first known successful attempt to disinfect wastewater in a disease outbreak setting without resorting to the alternative, untested, approach of ‘super chlorination’ which, it has been suggested, may not consistently achieve adequate disinfection. A basic analysis of costs demonstrated a significant saving in reagent costs compared with the less reliable approach of super-chlorination. The proposed approach to in situ sanitation in cholera treatment centers and other disease outbreak settings represents a timely response to a UN call for onsite disinfection of wastewaters generated in such emergencies, and the ‘Coalition for Cholera Prevention and Control’ recently highlighted the research as meriting serious consideration and further study. Further applications of the method to other emergency settings are being actively explored by the authors through discussion with the World Health Organization with regards to the ongoing Ebola outbreak in West Africa, and with the UK-based NGO Oxfam with regards to excreta-borne disease management in the Philippines and Myanmar, as a component of post-disaster incremental improvements to local sanitation chains. When an outbreak of infectious disease occurs in a low-resource setting, the rapid construction of emergency healthcare facilities may significantly reduce mortality. The facilities also result in the generation of large volumes of highly contaminated fecal waste that represents a potential basis for further disease transmission. Infection protection and control strategies at healthcare facilities must therefore include measures to establish and maintain good water supplies, sanitation and hygiene (WASH). Even where the pathogen of concern is not waterborne, health-care providers have a ‘duty-of-care’ to protect workers and neighboring communities from all excreta-borne diseases. In this study, the authors successfully demonstrated, for the first time, the in situ disinfection of wastewaters from cholera treatment centers during the Haiti cholera outbreak, using a low-cost physicochemical method. The approach is currently being adapted by NGOs to help manage human excreta in other emergency settings, including the current Ebola outbreak. Although the Ebola virus is relatively fragile, it may exist in high concentrations in the bodily fluids (including feces) of those with the disease. The approach to in situ disinfection of excreta described here may therefore support infection control in outbreaks of Ebola and other infectious diseases.
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18
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Walz Y, Wegmann M, Dech S, Raso G, Utzinger J. Risk profiling of schistosomiasis using remote sensing: approaches, challenges and outlook. Parasit Vectors 2015; 8:163. [PMID: 25890278 PMCID: PMC4406176 DOI: 10.1186/s13071-015-0732-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 02/12/2015] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Schistosomiasis is a water-based disease that affects an estimated 250 million people, mainly in sub-Saharan Africa. The transmission of schistosomiasis is spatially and temporally restricted to freshwater bodies that contain schistosome cercariae released from specific snails that act as intermediate hosts. Our objective was to assess the contribution of remote sensing applications and to identify remaining challenges in its optimal application for schistosomiasis risk profiling in order to support public health authorities to better target control interventions. METHODS We reviewed the literature (i) to deepen our understanding of the ecology and the epidemiology of schistosomiasis, placing particular emphasis on remote sensing; and (ii) to fill an identified gap, namely interdisciplinary research that bridges different strands of scientific inquiry to enhance spatially explicit risk profiling. As a first step, we reviewed key factors that govern schistosomiasis risk. Secondly, we examined remote sensing data and variables that have been used for risk profiling of schistosomiasis. Thirdly, the linkage between the ecological consequence of environmental conditions and the respective measure of remote sensing data were synthesised. RESULTS We found that the potential of remote sensing data for spatial risk profiling of schistosomiasis is - in principle - far greater than explored thus far. Importantly though, the application of remote sensing data requires a tailored approach that must be optimised by selecting specific remote sensing variables, considering the appropriate scale of observation and modelling within ecozones. Interestingly, prior studies that linked prevalence of Schistosoma infection to remotely sensed data did not reflect that there is a spatial gap between the parasite and intermediate host snail habitats where disease transmission occurs, and the location (community or school) where prevalence measures are usually derived from. CONCLUSIONS Our findings imply that the potential of remote sensing data for risk profiling of schistosomiasis and other neglected tropical diseases has yet to be fully exploited.
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Affiliation(s)
- Yvonne Walz
- Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany. .,United Nations University - Institute for Environment and Human Security, Bonn, Germany.
| | - Martin Wegmann
- Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany.
| | - Stefan Dech
- Department of Remote Sensing, Institute for Geography and Geology, University of Würzburg, Würzburg, Germany. .,German Remote Sensing Data Centre, German Aerospace Centre, Oberpfaffenhofen, Germany.
| | - Giovanna Raso
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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Grimes JET, Croll D, Harrison WE, Utzinger J, Freeman MC, Templeton MR. The roles of water, sanitation and hygiene in reducing schistosomiasis: a review. Parasit Vectors 2015; 8:156. [PMID: 25884172 PMCID: PMC4377019 DOI: 10.1186/s13071-015-0766-9] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 02/18/2015] [Indexed: 11/10/2022] Open
Abstract
Schistosomiasis is a disease caused by infection with blood flukes of the genus Schistosoma. Transmission of, and exposure to, the parasite result from faecal or urinary contamination of freshwater containing intermediate host snails, and dermal contact with the same water. The World Health Assembly resolution 65.21 from May 2012 urges member states to eliminate schistosomiasis through preventive chemotherapy (i.e. periodic large-scale administration of the antischistosomal drug praziquantel to school-aged children and other high-risk groups), provision of water, sanitation and hygiene (WASH) and snail control. However, control measures focus almost exclusively on preventive chemotherapy, while only few studies made an attempt to determine the impact of upgraded access to safe water, adequate sanitation and good hygiene on schistosome transmission. We recently completed a systematic review and meta-analysis pertaining to WASH and schistosomiasis and found that people with safe water and adequate sanitation have significantly lower odds of a Schistosoma infection. Importantly though, the transmission of schistosomiasis is deeply entrenched in social-ecological systems, and hence is governed by setting-specific cultural and environmental factors that determine human behaviour and snail populations. Here, we provide a comprehensive review of the literature, which explores the transmission routes of schistosomes, particularly focussing on how these might be disrupted with WASH-related technologies and human behaviour. Additionally, future research directions in this area are highlighted.
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Affiliation(s)
- Jack E T Grimes
- Department of Civil and Environmental Engineering, Imperial College London, London, SW7 2AZ, UK.
| | - David Croll
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, , CH-4002, Basel, Switzerland. .,University of Basel, P.O. Box, , CH-4003, Basel, Switzerland.
| | - Wendy E Harrison
- Schistosomiasis Control Initiative, Imperial College London, London, SW7 2AZ, UK.
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, , CH-4002, Basel, Switzerland. .,University of Basel, P.O. Box, , CH-4003, Basel, Switzerland.
| | - Matthew C Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, 30322, USA.
| | - Michael R Templeton
- Department of Civil and Environmental Engineering, Imperial College London, London, SW7 2AZ, UK.
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Belizario VY, Liwanag HJC, Naig JRA, Chua PLC, Madamba MI, Dahildahil RO. Parasitological and nutritional status of school-age and preschool-age children in four villages in Southern Leyte, Philippines: Lessons for monitoring the outcome of Community-Led Total Sanitation. Acta Trop 2015; 141:16-24. [PMID: 25255966 DOI: 10.1016/j.actatropica.2014.09.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 08/01/2014] [Accepted: 09/14/2014] [Indexed: 10/24/2022]
Abstract
While preventive chemotherapy remains to be a major strategy for the prevention and control of soil-transmitted helminthiases (STH), improvements in water, sanitation, and hygiene (WASH) comprise the long-term strategy to achieve sustained control of STH. This study examined the parasitological and nutritional status of school-age and preschool-age children in four villages in Southern Leyte, Philippines where two of the villages attained Open-Defecation-Free (ODF) status after introduction of Community-Led Total Sanitation (CLTS). A total of 341 children (89.0% of the total eligible population) submitted stool samples which were examined using the Kato-Katz technique. Results showed that 27.9% of the total stool samples examined had at least one type of STH (cumulative prevalence), while 7.9% had moderate-heavy intensity infections. Between the two villages where CLTS was introduced, Buenavista had a significantly higher cumulative prevalence of STH at 67.4% (p<0.001) and prevalence of moderate-heavy intensity STH at 23.5% (p=0.000), while Caubang had a significantly lower cumulative prevalence at 4.9% and prevalence of moderate-heavy intensity at 1.8%. On the other hand, the non-CLTS villages of Bitoon and Saub had similar rates for cumulative prevalence (16.7% and 16.8%, respectively; p=0.984) and prevalence of moderate-heavy intensity STH (2.0% and 3.1%, respectively; p=1.000). The findings may be explained by factors that include possible reversion to open defecation, non-utilization of sanitary facilities, and mass drug administration (MDA) coverage, although further studies that can accurately assess the impact of CLTS are recommended. While this study was descriptive, the data indicate no clear pattern among the parasitological and nutritional parameters, as well as the presence of CLTS in the village, suggesting the need to monitor the ODF status of villages on a regular basis even after the end of CLTS activities to ensure the sustainability of the CLTS approach. In order to achieve effective control of STH, deeper collaboration between the WASH and STH sectors are recommended where partners can work together in the area of monitoring and evaluation that may include improved parasitological and nutritional status in high-risk groups, as well as sustainable behavior change as outcome indicators.
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Integrated control programmes for schistosomiasis and other helminth infections in P.R. China. Acta Trop 2015; 141:332-41. [PMID: 24361182 DOI: 10.1016/j.actatropica.2013.11.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 10/26/2013] [Accepted: 11/30/2013] [Indexed: 02/08/2023]
Abstract
The prevalence of human schistosomiasis and soil-transmitted helminthiasis (STH) has decreased significantly in the People's Republic of China (P.R. China), particularly after 2005 when the national control programmes were reinforced by forming of integrated control strategies. Furthermore, social-economic development also contributed to the decrease of schistosome and soil-transmitted helminth infections. The prevalence of the zoonotic helminthiasis, including clonorchiasis and echinococcosis, on the other hand, is either underestimated or has in fact increased due to changes in social and environmental factors. In comparison with the control strategies in force and their effects on those four kinds of helminthiasis, the challenges and control priorities for the potential transfer from control to elimination of each disease is reviewed, to provide evidence for policy-makers to act upon.
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Grimes JET, Croll D, Harrison WE, Utzinger J, Freeman MC, Templeton MR. The relationship between water, sanitation and schistosomiasis: a systematic review and meta-analysis. PLoS Negl Trop Dis 2014; 8:e3296. [PMID: 25474705 PMCID: PMC4256273 DOI: 10.1371/journal.pntd.0003296] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 09/24/2014] [Indexed: 11/26/2022] Open
Abstract
Background Access to “safe” water and “adequate” sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review. Methodology We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I2. Principal Findings Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR) = 0.53, 95% confidence interval (CI): 0.47–0.61). Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47–0.73) and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57–0.84). Included studies were mainly cross-sectional and quality was largely poor. Conclusions/Significance Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human behavior, and schistosome transmission. Schistosomiasis is a serious disease in many developing countries, and the control of schistosomiasis relies on the large-scale administration of praziquantel. However, this strategy fails to address the root causes of schistosomiasis, which people acquire during contact with freshwater bodies that contain infected snails. It is suggested that improving access to clean water and sanitation reduces the risk of schistosomiasis transmission. Moreover, the use of soap, detergent, and endod (a berry sometimes used as a substitute for soap) might kill snails and the parasite larvae they excrete. We systematically reviewed the literature and performed a meta-analysis to study the association between people's access to clean water, sanitation, and good hygiene and the risk of schistosomiasis. People with access to clean water and adequate sanitation were at lower risks of schistosomiasis. No studies were found to explore the relationship between hygiene and risk of schistosomiasis. The difference in infection rates between people with and without access to clean water and sanitation varies widely between studies, suggesting that the impact of water and sanitation on schistosomiasis transmission is mediated by many other social and environmental factors. Further research is needed on the impact of water, sanitation and hygiene interventions for schistosomiasis control.
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Affiliation(s)
- Jack E. T. Grimes
- Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
- * E-mail:
| | - David Croll
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Wendy E. Harrison
- Schistosomiasis Control Initiative, Imperial College London, London, United Kingdom
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Matthew C. Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Michael R. Templeton
- Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
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Tomczyk S, Deribe K, Brooker SJ, Clark H, Rafique K, Knopp S, Utzinger J, Davey G. Association between footwear use and neglected tropical diseases: a systematic review and meta-analysis. PLoS Negl Trop Dis 2014; 8:e3285. [PMID: 25393620 PMCID: PMC4230915 DOI: 10.1371/journal.pntd.0003285] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 09/22/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The control of neglected tropical diseases (NTDs) has primarily focused on preventive chemotherapy and case management. Less attention has been placed on the role of ensuring access to adequate water, sanitation, and hygiene and personal preventive measures in reducing exposure to infection. Our aim was to assess whether footwear use was associated with a lower risk of selected NTDs. METHODOLOGY We conducted a systematic review and meta-analysis to assess the association between footwear use and infection or disease for those NTDs for which the route of transmission or occurrence may be through the feet. We included Buruli ulcer, cutaneous larva migrans (CLM), leptospirosis, mycetoma, myiasis, podoconiosis, snakebite, tungiasis, and soil-transmitted helminth (STH) infections, particularly hookworm infection and strongyloidiasis. We searched Medline, Embase, Cochrane, Web of Science, CINAHL Plus, and Popline databases, contacted experts, and hand-searched reference lists for eligible studies. The search was conducted in English without language, publication status, or date restrictions up to January 2014. Studies were eligible for inclusion if they reported a measure of the association between footwear use and the risk of each NTD. Publication bias was assessed using funnel plots. Descriptive study characteristics and methodological quality of the included studies were summarized. For each study outcome, both outcome and exposure data were abstracted and crude and adjusted effect estimates presented. Individual and summary odds ratio (OR) estimates and corresponding 95% confidence intervals (CIs) were calculated as a measure of intervention effect, using random effects meta-analyses. PRINCIPAL FINDINGS Among the 427 studies screened, 53 met our inclusion criteria. Footwear use was significantly associated with a lower odds of infection of Buruli ulcer (OR=0.15; 95% CI: 0.08-0.29), CLM (OR=0.24; 95% CI: 0.06-0.96), tungiasis (OR=0.42; 95% CI: 0.26-0.70), hookworm infection (OR=0.48; 95% CI: 0.37-0.61), any STH infection (OR=0.57; 95% CI: 0.39-0.84), strongyloidiasis (OR=0.56; 95% CI: 0.38-0.83), and leptospirosis (OR=0.59; 95% CI: 0.37-0.94). No significant association between footwear use and podoconiosis (OR=0.63; 95% CI: 0.38-1.05) was found and no data were available for mycetoma, myiasis, and snakebite. The main limitations were evidence of heterogeneity and poor study quality inherent to the observational studies included. CONCLUSIONS/SIGNIFICANCE Our results show that footwear use was associated with a lower odds of several different NTDs. Access to footwear should be prioritized alongside existing NTD interventions to ensure a lasting reduction of multiple NTDs and to accelerate their control and elimination. PROTOCOL REGISTRATION PROSPERO International prospective register of systematic reviews CRD42012003338.
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Affiliation(s)
- Sara Tomczyk
- Institute of Tropical Medicine, Antwerp, Belgium
| | - Kebede Deribe
- Brighton & Sussex Medical School, Brighton, United Kingdom
- School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Simon J. Brooker
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Hannah Clark
- Brighton & Sussex Medical School, Brighton, United Kingdom
| | - Khizar Rafique
- Brighton & Sussex Medical School, Brighton, United Kingdom
| | - Stefanie Knopp
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Gail Davey
- Brighton & Sussex Medical School, Brighton, United Kingdom
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Hawdon JM. Controlling Soil-Transmitted Helminths: Time to Think Inside the Box? J Parasitol 2014; 100:166-88. [DOI: 10.1645/13-412.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Pullan RL, Freeman MC, Gething PW, Brooker SJ. Geographical inequalities in use of improved drinking water supply and sanitation across Sub-Saharan Africa: mapping and spatial analysis of cross-sectional survey data. PLoS Med 2014; 11:e1001626. [PMID: 24714528 PMCID: PMC3979660 DOI: 10.1371/journal.pmed.1001626] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/27/2014] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Understanding geographic inequalities in coverage of drinking-water supply and sanitation (WSS) will help track progress towards universal coverage of water and sanitation by identifying marginalized populations, thus helping to control a large number of infectious diseases. This paper uses household survey data to develop comprehensive maps of WSS coverage at high spatial resolution for sub-Saharan Africa (SSA). Analysis is extended to investigate geographic heterogeneity and relative geographic inequality within countries. METHODS AND FINDINGS Cluster-level data on household reported use of improved drinking-water supply, sanitation, and open defecation were abstracted from 138 national surveys undertaken from 1991-2012 in 41 countries. Spatially explicit logistic regression models were developed and fitted within a Bayesian framework, and used to predict coverage at the second administrative level (admin2, e.g., district) across SSA for 2012. Results reveal substantial geographical inequalities in predicted use of water and sanitation that exceed urban-rural disparities. The average range in coverage seen between admin2 within countries was 55% for improved drinking water, 54% for use of improved sanitation, and 59% for dependence upon open defecation. There was also some evidence that countries with higher levels of inequality relative to coverage in use of an improved drinking-water source also experienced higher levels of inequality in use of improved sanitation (rural populations r = 0.47, p = 0.002; urban populations r = 0.39, p = 0.01). Results are limited by the quantity of WSS data available, which varies considerably by country, and by the reliability and utility of available indicators. CONCLUSIONS This study identifies important geographic inequalities in use of WSS previously hidden within national statistics, confirming the necessity for targeted policies and metrics that reach the most marginalized populations. The presented maps and analysis approach can provide a mechanism for monitoring future reductions in inequality within countries, reflecting priorities of the post-2015 development agenda. Please see later in the article for the Editors' Summary.
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Affiliation(s)
- Rachel L. Pullan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Matthew C. Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Peter W. Gething
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Simon J. Brooker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
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Strunz EC, Addiss DG, Stocks ME, Ogden S, Utzinger J, Freeman MC. Water, sanitation, hygiene, and soil-transmitted helminth infection: a systematic review and meta-analysis. PLoS Med 2014; 11:e1001620. [PMID: 24667810 PMCID: PMC3965411 DOI: 10.1371/journal.pmed.1001620] [Citation(s) in RCA: 433] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 02/13/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Preventive chemotherapy represents a powerful but short-term control strategy for soil-transmitted helminthiasis. Since humans are often re-infected rapidly, long-term solutions require improvements in water, sanitation, and hygiene (WASH). The purpose of this study was to quantitatively summarize the relationship between WASH access or practices and soil-transmitted helminth (STH) infection. METHODS AND FINDINGS We conducted a systematic review and meta-analysis to examine the associations of improved WASH on infection with STH (Ascaris lumbricoides, Trichuris trichiura, hookworm [Ancylostoma duodenale and Necator americanus], and Strongyloides stercoralis). PubMed, Embase, Web of Science, and LILACS were searched from inception to October 28, 2013 with no language restrictions. Studies were eligible for inclusion if they provided an estimate for the effect of WASH access or practices on STH infection. We assessed the quality of published studies with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. A total of 94 studies met our eligibility criteria; five were randomized controlled trials, whilst most others were cross-sectional studies. We used random-effects meta-analyses and analyzed only adjusted estimates to help account for heterogeneity and potential confounding respectively. Use of treated water was associated with lower odds of STH infection (odds ratio [OR] 0.46, 95% CI 0.36-0.60). Piped water access was associated with lower odds of A. lumbricoides (OR 0.40, 95% CI 0.39-0.41) and T. trichiura infection (OR 0.57, 95% CI 0.45-0.72), but not any STH infection (OR 0.93, 95% CI 0.28-3.11). Access to sanitation was associated with decreased likelihood of infection with any STH (OR 0.66, 95% CI 0.57-0.76), T. trichiura (OR 0.61, 95% CI 0.50-0.74), and A. lumbricoides (OR 0.62, 95% CI 0.44-0.88), but not with hookworm infection (OR 0.80, 95% CI 0.61-1.06). Wearing shoes was associated with reduced odds of hookworm infection (OR 0.29, 95% CI 0.18-0.47) and infection with any STH (OR 0.30, 95% CI 0.11-0.83). Handwashing, both before eating (OR 0.38, 95% CI 0.26-0.55) and after defecating (OR 0.45, 95% CI 0.35-0.58), was associated with lower odds of A. lumbricoides infection. Soap use or availability was significantly associated with lower infection with any STH (OR 0.53, 95% CI 0.29-0.98), as was handwashing after defecation (OR 0.47, 95% CI 0.24-0.90). Observational evidence constituted the majority of included literature, which limits any attempt to make causal inferences. Due to underlying heterogeneity across observational studies, the meta-analysis results reflect an average of many potentially distinct effects, not an average of one specific exposure-outcome relationship. CONCLUSIONS WASH access and practices are generally associated with reduced odds of STH infection. Pooled estimates from all meta-analyses, except for two, indicated at least a 33% reduction in odds of infection associated with individual WASH practices or access. Although most WASH interventions for STH have focused on sanitation, access to water and hygiene also appear to significantly reduce odds of infection. Overall quality of evidence was low due to the preponderance of observational studies, though recent randomized controlled trials have further underscored the benefit of handwashing interventions. Limited use of the Joint Monitoring Program's standardized water and sanitation definitions in the literature restricted efforts to generalize across studies. While further research is warranted to determine the magnitude of benefit from WASH interventions for STH control, these results call for multi-sectoral, integrated intervention packages that are tailored to social-ecological contexts.
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Affiliation(s)
- Eric C. Strunz
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - David G. Addiss
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - Meredith E. Stocks
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Stephanie Ogden
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
- International Trachoma Initiative, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Matthew C. Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
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Smits HL. Prospects for the control of neglected tropical diseases by mass drug administration. Expert Rev Anti Infect Ther 2014; 7:37-56. [DOI: 10.1586/14787210.7.1.37] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Hotez PJ, Bethony JM, Oliveira SC, Brindley PJ, Loukas A. Multivalent anthelminthic vaccine to prevent hookworm and schistosomiasis. Expert Rev Vaccines 2014; 7:745-52. [DOI: 10.1586/14760584.7.6.745] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Elimination and eradication of neglected tropical diseases with mass drug administrations: a survey of experts. PLoS Negl Trop Dis 2013; 7:e2562. [PMID: 24340111 PMCID: PMC3855072 DOI: 10.1371/journal.pntd.0002562] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 10/14/2013] [Indexed: 11/19/2022] Open
Abstract
Background Lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths, and trachoma are the five most prevalent neglected tropical diseases in the world, and each is frequently treated with mass drug administrations. We performed a survey of neglected tropical diseases experts to elicit their opinions on the role of mass drug administrations for the elimination of these infections. Methodology/Principal Findings We sent an online survey to corresponding authors who had published an article about a neglected tropical disease from 2007 to 2011. Of 825 unique authors who were invited to complete the survey, 365 (44.2%) responded, including 234 (28.4%) who answered questions regarding one of the five most prevalent neglected tropical diseases. Respondents had varying opinions about the goals of programmatic activities for their chosen neglected tropical disease, with elimination or eradication identified as the most important goal by 87% of lymphatic filariasis respondents, 66% of onchocerciasis respondents, 55% of trachoma respondents, 24% of schistosomiasis respondents, and 21% of soil-transmitted helminth respondents. Mass drug administrations, other non-medication health measures, and education were generally thought to be more important for elimination than vector control, development of a new tool, or the presence of a secular trend. Drug resistance was thought to be a major limitation of mass drug administrations for all five neglected tropical diseases. Over half of respondents for lymphatic filariasis and trachoma thought that repeated mass drug administrations could eliminate infection within ten years of the initiation of mass treatments. Conclusions/Significance Respondents for lymphatic filariasis, onchocerciasis, and trachoma were more enthusiastic about the prospects of elimination and eradication than were respondents for schistosomiasis or soil-transmitted helminths. Mass drug administrations were generally believed to be among the most important factors for the success of elimination efforts for each of the five neglected tropical diseases, highlighting the opportunity for integrating drug distributions. Mass drug administrations are used for each of the five most common neglected tropical diseases: lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths, and trachoma. Three of these infections—lymphatic filariasis, onchocerciasis, and trachoma—are officially targeted for elimination, and mass drug administrations play a key role in the elimination plans for each. While progress has been demonstrated for each of these diseases, it is unclear whether researchers of these diseases think that elimination is feasible, or whether mass drug administrations should play an important role given the potential for drug resistance. We performed a survey of neglected tropical diseases experts to assess their opinions on the likelihood of elimination and the role of mass drug administrations for the five most common neglected tropical diseases. Most experts in lymphatic filariasis, onchocerciasis, and trachoma thought elimination was the appropriate goal of treatment programs, whereas most experts in schistosomiasis and soil-transmitted helminths thought that treatment programs were intended to control, but not eliminate, infection. Drug resistance was thought to be a major limitation for each of the infections. Although there were differences between the five infections, mass drug administrations, non-medication health measures, and education were generally thought to be the most important pieces of a control program.
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Rollinson D, Knopp S, Levitz S, Stothard JR, Tchuem Tchuenté LA, Garba A, Mohammed KA, Schur N, Person B, Colley DG, Utzinger J. Time to set the agenda for schistosomiasis elimination. Acta Trop 2013; 128:423-40. [PMID: 22580511 DOI: 10.1016/j.actatropica.2012.04.013] [Citation(s) in RCA: 376] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 04/25/2012] [Accepted: 04/27/2012] [Indexed: 12/19/2022]
Abstract
It is time to raise global awareness to the possibility of schistosomiasis elimination and to support endemic countries in their quest to determine the most appropriate approaches to eliminate this persistent and debilitating disease. The main interventions for schistosomiasis control are reviewed, including preventive chemotherapy using praziquantel, snail control, sanitation, safe water supplies, and behaviour change strategies supported by information, education and communication (IEC) materials. Differences in the biology and transmission of the three main Schistosoma species (i.e. Schistosoma haematobium, S. mansoni and S. japonicum), which impact on control interventions, are considered. Sensitive diagnostic procedures to ensure adequate surveillance in areas attaining low endemicity are required. The importance of capacity building is highlighted. To achieve elimination, an intersectoral approach is necessary, with advocacy and action from local communities and the health community to foster cooperative ventures with engineers, the private sector, governments and non-governmental organizations specialized in water supply and sanitation. Examples of successful schistosomiasis control programmes are reviewed to highlight what has been learnt in terms of strategy for control and elimination. These include St. Lucia and other Caribbean islands, Brazil and Venezuela for S. mansoni; Saudi Arabia and Egypt for both S. mansoni and S. haematobium; Morocco, Tunisia, Algeria, Mauritius and the Islamic Republic of Iran for S. haematobium; Japan and the People's Republic of China for S. japonicum. Additional targets for elimination or even eradication could be the two minor human schistosome species S. guineenisis and S. intercalatum, which have a restricted distribution in West and Central Africa. The examples show that elimination of schistosomiasis is an achievable and desirable goal requiring full integration of preventive chemotherapy with the tools of transmission control. An agenda for the elimination of schistosomiasis would aim to identify the gaps in knowledge, and define the tools, strategies and guidelines that will help national control programmes move towards elimination, including an internationally accepted mechanism that allows verification/confirmation of elimination.
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Affiliation(s)
- David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, Cromwell Road, London SW7 5BD, UK.
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Knopp S, Person B, Ame SM, Mohammed KA, Ali SM, Khamis IS, Rabone M, Allan F, Gouvras A, Blair L, Fenwick A, Utzinger J, Rollinson D. Elimination of schistosomiasis transmission in Zanzibar: baseline findings before the onset of a randomized intervention trial. PLoS Negl Trop Dis 2013; 7:e2474. [PMID: 24147165 PMCID: PMC3798599 DOI: 10.1371/journal.pntd.0002474] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 08/28/2013] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Gaining and sustaining control of schistosomiasis and, whenever feasible, achieving local elimination are the year 2020 targets set by the World Health Organization. In Zanzibar, various institutions and stakeholders have joined forces to eliminate urogenital schistosomiasis within 5 years. We report baseline findings before the onset of a randomized intervention trial designed to assess the differential impact of community-based praziquantel administration, snail control, and behavior change interventions. METHODOLOGY In early 2012, a baseline parasitological survey was conducted in ~20,000 people from 90 communities in Unguja and Pemba. Risk factors for schistosomiasis were assessed by administering a questionnaire to adults. In selected communities, local knowledge about schistosomiasis transmission and prevention was determined in focus group discussions and in-depths interviews. Intermediate host snails were collected and examined for shedding of cercariae. PRINCIPAL FINDINGS The baseline Schistosoma haematobium prevalence in school children and adults was 4.3% (range: 0-19.7%) and 2.7% (range: 0-26.5%) in Unguja, and 8.9% (range: 0-31.8%) and 5.5% (range: 0-23.4%) in Pemba, respectively. Heavy infections were detected in 15.1% and 35.6% of the positive school children in Unguja and Pemba, respectively. Males were at higher risk than females (odds ratio (OR): 1.45; 95% confidence interval (CI): 1.03-2.03). Decreasing adult age (OR: 1.04; CI: 1.02-1.06), being born in Pemba (OR: 1.48; CI: 1.02-2.13) or Tanzania (OR: 2.36; CI: 1.16-4.78), and use of freshwater (OR: 2.15; CI: 1.53-3.03) showed higher odds of infection. Community knowledge about schistosomiasis was low. Only few infected Bulinus snails were found. CONCLUSIONS/SIGNIFICANCE The relatively low S. haematobium prevalence in Zanzibar is a promising starting point for elimination. However, there is a need to improve community knowledge about disease transmission and prevention. Control measures tailored to the local context, placing particular attention to hot-spot areas, high-risk groups, and individuals, will be necessary if elimination is to be achieved.
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Affiliation(s)
- Stefanie Knopp
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| | - Bobbie Person
- Schistosomiasis Consortium for Operational Research and Evaluation, Athens, Georgia, United States of America
| | - Shaali M. Ame
- Public Health Laboratory - Ivo de Carneri, Pemba, United Republic of Tanzania
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Khalfan A. Mohammed
- Helminth Control Laboratory Unguja, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Said M. Ali
- Public Health Laboratory - Ivo de Carneri, Pemba, United Republic of Tanzania
| | - I. Simba Khamis
- Helminth Control Laboratory Unguja, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Muriel Rabone
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Fiona Allan
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Anouk Gouvras
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Lynsey Blair
- Schistosomiasis Control Initiative, Department of Infectious Disease Epidemiology, Faculty of Medicine, London, United Kingdom
| | - Alan Fenwick
- Schistosomiasis Control Initiative, Department of Infectious Disease Epidemiology, Faculty of Medicine, London, United Kingdom
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
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Knopp S, Becker SL, Ingram KJ, Keiser J, Utzinger J. Diagnosis and treatment of schistosomiasis in children in the era of intensified control. Expert Rev Anti Infect Ther 2013; 11:1237-58. [PMID: 24127662 DOI: 10.1586/14787210.2013.844066] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In the current era of intensified and integrated control against schistosomiasis and other neglected tropical diseases, there is a need to carefully rethink and take into consideration disease-specific issues pertaining to the diagnosis, prevention, control and local elimination. Here, we present a comprehensive overview about schistosomiasis including recent trends in the number of people treated with praziquantel and the latest developments in diagnosis and control. Particular emphasis is placed on children. Identified research needs are offered for consideration; namely, expanding our knowledge about schistosomiasis in preschool-aged children, assessing and quantifying the impact of schistosomiasis on infectious and noncommunicable diseases, developing new antischistosomal drugs and child-friendly formulations, designing and implementing setting-specific control packages and developing highly sensitive, but simple diagnostic tools that are able to detect very light infections in young children and in people living in areas targeted for schistosomiasis elimination.
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Affiliation(s)
- Stefanie Knopp
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002, Basel, Switzerland
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Freeman MC, Ogden S, Jacobson J, Abbott D, Addiss DG, Amnie AG, Beckwith C, Cairncross S, Callejas R, Colford JM, Emerson PM, Fenwick A, Fishman R, Gallo K, Grimes J, Karapetyan G, Keene B, Lammie PJ, MacArthur C, Lochery P, Petach H, Platt J, Prabasi S, Rosenboom JW, Roy S, Saywell D, Schechtman L, Tantri A, Velleman Y, Utzinger J. Integration of water, sanitation, and hygiene for the prevention and control of neglected tropical diseases: a rationale for inter-sectoral collaboration. PLoS Negl Trop Dis 2013; 7:e2439. [PMID: 24086781 PMCID: PMC3784463 DOI: 10.1371/journal.pntd.0002439] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Improvements of water, sanitation, and hygiene (WASH) infrastructure and appropriate health-seeking behavior are necessary for achieving sustained control, elimination, or eradication of many neglected tropical diseases (NTDs). Indeed, the global strategies to fight NTDs include provision of WASH, but few programs have specific WASH targets and approaches. Collaboration between disease control programs and stakeholders in WASH is a critical next step. A group of stakeholders from the NTD control, child health, and WASH sectors convened in late 2012 to discuss opportunities for, and barriers to, collaboration. The group agreed on a common vision, namely "Disease-free communities that have adequate and equitable access to water and sanitation, and that practice good hygiene." Four key areas of collaboration were identified, including (i) advocacy, policy, and communication; (ii) capacity building and training; (iii) mapping, data collection, and monitoring; and (iv) research. We discuss strategic opportunities and ways forward for enhanced collaboration between the WASH and the NTD sectors.
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Affiliation(s)
- Matthew C. Freeman
- Department of Environmental Health, Emory University, Atlanta, Georgia, United States of America
| | - Stephanie Ogden
- Department of Environmental Health, Emory University, Atlanta, Georgia, United States of America
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
- International Trachoma Initiative, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Julie Jacobson
- Bill & Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Daniel Abbott
- Save the Children, Washington, D.C., United States of America
| | - David G. Addiss
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Asrat G. Amnie
- Hubert Department of Global Health, Emory University, Atlanta, Georgia, United States of America
| | - Colin Beckwith
- International Trachoma Initiative, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Sandy Cairncross
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Rafael Callejas
- Millennium Water Alliance, Washington, D.C., United States of America
| | - Jack M. Colford
- Department of Epidemiology, University of California-Berkeley, Berkeley, California, United States of America
| | - Paul M. Emerson
- The Carter Center, Atlanta, Georgia, United States of America
| | - Alan Fenwick
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | | | - Kerry Gallo
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Jack Grimes
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
- Department of Civil and Environmental Engineering, Imperial College, London, United Kingdom
| | | | - Brooks Keene
- CARE International, Atlanta, Georgia, United States of America
| | - Patrick J. Lammie
- Taskforce for Global Health, Atlanta, Georgia, United States of America
- Center for Global Health, United States Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Chad MacArthur
- Helen Keller International, New York, New York, United States of America
| | - Peter Lochery
- CARE International, Atlanta, Georgia, United States of America
| | - Helen Petach
- United States Agency for International Development, Washington, D.C., United States of America
| | - Jennifer Platt
- WASH Advocates, Washington, D.C., United States of America
| | - Sarina Prabasi
- ORBIS International, New York, New York, United States of America
| | | | - Sharon Roy
- Waterborne Disease Prevention Branch, United States Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Darren Saywell
- Plan International, Washington, D.C., United States of America
| | - Lisa Schechtman
- WaterAid America, Washington, D.C., United States of America
| | - Anupama Tantri
- Sabin Vaccine Institute, Washington, D.C., United States of America
| | | | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Hu Y, Zhang Z, Chen Y, Wang Z, Gao J, Tao B, Jiang Q, Jiang Q. Spatial pattern of schistosomiasis in Xingzi, Jiangxi Province, China: the effects of environmental factors. Parasit Vectors 2013; 6:214. [PMID: 23880253 PMCID: PMC3726341 DOI: 10.1186/1756-3305-6-214] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Accepted: 07/18/2013] [Indexed: 11/29/2022] Open
Abstract
Background The recent rebounds of schistosomiasis in the middle and lower reaches of the Yangtze River pose a challenge to the current control strategies. In this study, identification of potential high risk snail habitats was proposed, as an alternative sustainable control strategy, in Xingzi County, China. Parasitological data from standardized surveys were available for 36,208 locals (aged between 6–65 years) from 42 sample villages across the county and used in combination with environmental data to investigate the spatial pattern of schistosomiasis risks. Methods Environmental factors measured at village level were examined as possible risk factors by fitting a logistic regression model to schsitosomiasis risk. The approach of ordinary kriging was then used to predict the prevalence of schistosomiasis over the whole county. Results Risk analysis indicated that distance to snail habitat and wetland, rainfall, land surface temperature, hours of daylight, and vegetation are significantly associated with infection and the residual spatial pattern of infection showed no spatial correlation. The predictive map illustrated that high risk regions were located close to Beng Lake, Liaohuachi Lake, and Shixia Lake. Conclusions Those significant environmental factors can perfectly explain spatial variation in infection and the high risk snail habitats delineated by the predicted map of schistosomiasis risks will help local decision-makers to develop a more sustainable control strategy.
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Affiliation(s)
- Yi Hu
- Department of Epidemiology, School of Public Health, Fudan University, Shanghai 200032, China
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Schmidlin T, Hürlimann E, Silué KD, Yapi RB, Houngbedji C, Kouadio BA, Acka-Douabélé CA, Kouassi D, Ouattara M, Zouzou F, Bonfoh B, N’Goran EK, Utzinger J, Raso G. Effects of hygiene and defecation behavior on helminths and intestinal protozoa infections in Taabo, Côte d'Ivoire. PLoS One 2013; 8:e65722. [PMID: 23840358 PMCID: PMC3688730 DOI: 10.1371/journal.pone.0065722] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 04/26/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND More than 1 billion people are currently infected with soil-transmitted helminths and schistosomes. The global strategy to control helminthiases is the regular administration of anthelmintic drugs to at-risk populations. However, rapid re-infection occurs in areas where hygiene, access to clean water, and sanitation are inadequate. METHODOLOGY In July 2011, inhabitants from two villages and seven hamlets of the Taabo health demographic surveillance system in south-central Côte d'Ivoire provided stool and urine samples. Kato-Katz and ether-concentration methods were used for the diagnosis of Schistosoma mansoni, soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura, and hookworm), and intestinal protozoa. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. A questionnaire was administered to households to obtain information on knowledge, attitude, practice, and beliefs in relation to hygiene, sanitation, and defecation behavior. Logistic regression models were employed to assess for associations between questionnaire data and parasitic infections. PRINCIPAL FINDINGS A total of 1,894 participants had complete data records. Parasitological examinations revealed prevalences of hookworm, S. haematobium, T. trichiura, S. mansoni, and A. lumbricoides of 33.5%, 7.0%, 1.6%, 1.3% and 0.8%, respectively. Giardia intestinalis and Entamoeba histolytica/E. dispar were detected in 15.0% and 14.4% of the participants, respectively. Only one out of five households reported the presence of a latrine, and hence, open defecation was common. Logistic regression analysis revealed that age, sex, socioeconomic status, hygiene, and defecation behavior are determinants for helminths and intestinal protozoa infections. CONCLUSIONS/SIGNIFICANCE We found that inadequate sanitation and hygiene behavior are associated with soil-transmitted helminths and intestinal protozoa infections in the Taabo area of south-central Côte d'Ivoire. Our data will serve as a benchmark to monitor the effect of community-led total sanitation and hygiene education to reduce the transmission of helminthiases and intestinal protozoa infections.
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Affiliation(s)
- Thomas Schmidlin
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Eveline Hürlimann
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Kigbafori D. Silué
- Département Environnement et Santé, 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
| | - Richard B. Yapi
- Département Environnement et Santé, 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
| | - Clarisse Houngbedji
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Unité de Formation et de Recherche Sciences Naturelles, Université Nangui Abrogoua, Abidjan, Côte d’Ivoire
| | - Bernadette A. Kouadio
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Unité de Formation et de Recherche Communication, Milieu et Société, Université Alassane Ouattara, Bouaké, Côte d’Ivoire
| | - Cinthia A. Acka-Douabélé
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Dongo Kouassi
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Unité de Formation et de Recherche Sciences de la Terre et des Ressources Minières, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Fabien Zouzou
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Bassirou Bonfoh
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Eliézer K. N’Goran
- Département Environnement et Santé, 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
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Giovanna Raso
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
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Cost-effectiveness of a community-based intervention for reducing the transmission of Schistosoma haematobium and HIV in Africa. Proc Natl Acad Sci U S A 2013; 110:7952-7. [PMID: 23589884 DOI: 10.1073/pnas.1221396110] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Epidemiological studies from sub-Saharan Africa show that genital infection with Schistosoma haematobium [corrected] may increase the risk for HIV infection in young women. Therefore, preventing schistosomiasis has the potential to reduce HIV transmission in sub-Saharan Africa. We developed a transmission model of female genital schistosomiasis and HIV infections that we fit to epidemiological data of HIV and female genital schistosomiasis prevalence and coinfection in rural Zimbabwe. We used the model to evaluate the cost-effectiveness of a multifaceted community-based intervention for preventing schistosomiasis and, consequently, HIV infections in rural Zimbabwe, from the perspective of a health payer. The community-based intervention combined provision of clean water, sanitation, and health education (WSH) with administration of praziquantel to school-aged children. Considering variation in efficacy between 10% and 70% of WSH for reducing S. haematobium [corrected] transmission, our model predicted that community-based intervention is likely to be cost-effective in Zimbabwe at an aggregated WSH cost corresponding to US $725-$1,000 per individual over a 20-y intervention period. These costs compare favorably with empirical measures of WSH provision in developing countries, indicating that integrated community-based intervention for reducing the transmission of S. haematobium [corrected] is an economically attractive strategy for reducing schistosomiasis and HIV transmission in sub-Saharan Africa that would have a powerful impact on averting infections and saving lives.
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Winkler MS, Krieger GR, Divall MJ, Cissé G, Wielga M, Singer BH, Tanner M, Utzinger J. Untapped potential of health impact assessment. Bull World Health Organ 2013; 91:298-305. [PMID: 23599554 PMCID: PMC3629454 DOI: 10.2471/blt.12.112318] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 01/07/2013] [Accepted: 01/11/2013] [Indexed: 11/27/2022] Open
Abstract
The World Health Organization has promoted health impact assessment (HIA) for over 20 years. At the 2012 United Nations Conference on Sustainable Development (Rio+20), HIA was discussed as a critical method for linking health to "green economy" and "institutional framework" strategies for sustainable development. In countries having a high human development index (HDI), HIA has been added to the overall assessment suite that typically includes potential environmental and social impacts, but it is rarely required as part of the environmental and social impact assessment for large development projects. When they are performed, project-driven HIAs are governed by a combination of project proponent and multilateral lender performance standards rather than host country requirements. Not surprisingly, in low-HDI countries HIA is missing from the programme and policy arena in the absence of an external project driver. Major drivers of global change (e.g. population growth and urbanization, growing pressure on natural resources and climate change) inordinately affect low- and medium-HDI countries; however, in such countries HIA is conspicuously absent. If the cloak of HIA invisibility is to be removed, it must be shown that HIA is useful and beneficial and, hence, an essential component of the 21st century's sustainable development agenda. We analyse where and how HIA can become fully integrated into the impact assessment suite and argue that the impact of HIA must not remain obscure.
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Affiliation(s)
- Mirko S Winkler
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, CH-4051 Basel, Switzerland.
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Ríos-Osorio LA, Crespo-González JJ, Zapata-Tamayo MA. Etnometodología para la comprensión y el manejo de la Enfermedad de Chagas en las poblaciones indígenas Wiwa asentadas en la vertiente suroriental de la Sierra Nevada de Santa Marta. SAUDE E SOCIEDADE 2012. [DOI: 10.1590/s0104-12902012000200017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
El objetivo de este trabajo fue establecer prevalencia de la Enfermedad de Chagas en las comunidades Wiwa de la Sierra Nevada de Santa Marta trascendiendo el modelo de investigación biomédica sustentado en el paradigma positivista, e involucrando la dimensión sociocultural y ambiental que caracteriza este fenómeno, desde la sostenibilidad como un nuevo paradigma de las ciencias. Se realizó un muestreo probabilístico de las 15 comunidades Wiwa asentadas en la zona de San Juan del César, Departamento de la Guajira, se realizaron los procedimientos biomédicos definidos para investigaciones epidemiológicas, paralelamente se realizaron procedimientos culturales desde el saber tradicional de las comunidades Wiwa, garantizando la armonía de las comunidades ante la agresión biomédica de su espacio ambiental, social y cultural. Se obtuvo una prevalencia de 33.5%, concordante con las cifras de Enfermedad de Chagas encontradas en las otras vertientes de la sierra, reflejando condiciones similares que predisponen a la presencia de la enfermedad. Se estableció como esta enfermedad es inexistente en el sistema médico tradicional de los Wiwa, y sólo el insecto vector es reconocido aunque no considerado como agente perturbador de la salud de las comunidades. A partir de la consideración del vector como eje integrador de las dos culturas se describen las características sociales, ambientales y culturales que definen la Enfermedad de Chagas en los Wiwa y de esta forma, la posibilidad de su comprensión y manejo desde factores complementarios al modelo biomédico.
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Jia TW, Melville S, Utzinger J, King CH, Zhou XN. Soil-transmitted helminth reinfection after drug treatment: a systematic review and meta-analysis. PLoS Negl Trop Dis 2012; 6:e1621. [PMID: 22590656 PMCID: PMC3348161 DOI: 10.1371/journal.pntd.0001621] [Citation(s) in RCA: 276] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Accepted: 03/01/2012] [Indexed: 01/08/2023] Open
Abstract
Background Soil-transmitted helminth (STH) infections (i.e., Ascaris lumbricoides, hookworm, and Trichuris trichiura) affect more than a billion people. Preventive chemotherapy (i.e., repeated administration of anthelmintic drugs to at-risk populations), is the mainstay of control. This strategy, however, does not prevent reinfection. We performed a systematic review and meta-analysis to assess patterns and dynamics of STH reinfection after drug treatment. Methodology We systematically searched PubMed, ISI Web of Science, EMBASE, Cochrane Database of Systematic Reviews, China National Knowledge Infrastructure, WanFang Database, Chinese Scientific Journal Database, and Google Scholar. Information on study year, country, sample size, age of participants, diagnostic method, drug administration strategy, prevalence and intensity of infection pre- and posttreatment, cure and egg reduction rate, evaluation period posttreatment, and adherence was extracted. Pooled risk ratios from random-effects models were used to assess the risk of STH reinfection after treatment. Our protocol is available on PROSPERO, registration number: CRD42011001678. Principal Findings From 154 studies identified, 51 were included and 24 provided STH infection rates pre- and posttreatment, whereas 42 reported determinants of predisposition to reinfection. At 3, 6, and 12 months posttreatment, A. lumbricoides prevalence reached 26% (95% confidence interval (CI): 16–43%), 68% (95% CI: 60–76%) and 94% (95% CI: 88–100%) of pretreatment levels, respectively. For T. trichiura, respective reinfection prevalence were 36% (95% CI: 28–47%), 67% (95% CI: 42–100%), and 82% (95% CI: 62–100%), and for hookworm, 30% (95% CI: 26–34%), 55% (95% CI: 34–87%), and 57% (95% CI: 49–67%). Prevalence and intensity of reinfection were positively correlated with pretreatment infection status. Conclusion STH reinfections occur rapidly after treatment, particularly for A. lumbricoides and T. trichiura. Hence, there is a need for frequent anthelmintic drug administrations to maximize the benefit of preventive chemotherapy. Integrated control approaches emphasizing health education and environmental sanitation are needed to interrupt transmission of STH. Infections with soil-transmitted helminths (the roundworm Ascaris lumbricoides, the whipworm Trichuris trichiura, and hookworm) affect over 1 billion people, particularly rural communities in the developing world. The global strategy to control soil-transmitted helminth infections is ‘preventive chemotherapy’, which means large-scale administration of anthelmintic drugs to at-risk populations. However, because reinfection occurs after treatment, ‘preventive chemotherapy’ must be repeated regularly. Our systematic review and meta-analysis found that at 3, 6, and 12 months after treatment, A. lumbricoides prevalence reached 26% (95% confidence interval (CI): 16–43%), 68% (95% CI: 60–76%) and 94% (95% CI: 88–100%) of pretreatment levels, respectively. For T. trichiura, respective reinfection prevalence at these time points were 36% (95% CI: 28–47%), 67% (95% CI: 42–100%), and 82% (95% CI: 62–100%); and for hookworm, 30% (95% CI: 26–34%), 55% (95% CI: 34–87%), and 57% (95% CI: 49–67%). Prevalence and intensity of reinfection were positively correlated with pretreatment infection status. Our results suggest a frequent anthelmintic drug administration to maximize the benefit of preventive chemotherapy. Moreover, an integrated control strategy, consisting of preventive chemotherapy combined with health education and environmental sanitation is needed to interrupt transmission of soil-transmitted helminths.
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Affiliation(s)
- Tie-Wu Jia
- Key Laboratory on Biology of Parasites and Vectors, MOH, WHO Collaborating Center on Malaria, Schistosomiasis and Filariasis, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
- * E-mail: (T-WJ); (X-NZ)
| | - Sara Melville
- Hughes Hall College, Cambridge University, Cambridge, United Kingdom
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Charles H. King
- Center for Global Health and Diseases, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Xiao-Nong Zhou
- Key Laboratory on Biology of Parasites and Vectors, MOH, WHO Collaborating Center on Malaria, Schistosomiasis and Filariasis, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
- * E-mail: (T-WJ); (X-NZ)
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Affiliation(s)
- Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Zhao GH, Li J, Song HQ, Li XY, Chen F, Lin RQ, Yuan ZG, Weng YB, Hu M, Zou FC, Zhu XQ. A specific PCR assay for the identification and differentiation of Schistosoma japonicum geographical isolates in mainland China based on analysis of mitochondrial genome sequences. INFECTION GENETICS AND EVOLUTION 2012; 12:1027-36. [PMID: 22446475 DOI: 10.1016/j.meegid.2012.02.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Revised: 02/28/2012] [Accepted: 02/29/2012] [Indexed: 12/01/2022]
Abstract
In the present study, near-complete mt genome sequences for eight representative Schistosoma japonicum samples from seven endemic provinces in mainland China were analyzed. Sequence differences among the eight mt genomes of S. japonicum samples were 0.20-2.51%. Variation in protein-coding genes was greater than that in rRNA genes. The mt DNA sequences of S. japonicum samples from south-western (SW) China were 2 bp [position 11727-11728 within tRNA-Cys, microsatellite (AG) indel] longer than those of the parasites from the lower Yangtze/Zhejiang areas. Representative DNA sequencing confirmed that such (AG) indel could be exploited for identification and differentiation of S. japonicum populations in SW China's Yunnan and Sichuan province which have two (AG) repeats from those in all remaining endemic provinces along the Yangtze River below the Three Gorges regions or close to the east coast of China (e.g., Zhejiang) which have only one (AG) repeat. Phylogenetic analyses based on the concatenated amino acids of 12 protein-coding genes also showed that samples from SW China (Sichuan and Yunnan provinces), above the Three Gorges Dam, formed a distinct cluster. Based on this indel polymorphism, a pair of specific primers was designed and used to develop a specific-PCR polyacrylamide gel detection assay. There was an obvious length difference in the amplified PCR products between S. japonicum samples from the two endemic types. The specific-PCR assay allowed the specific identification of S. japonicum, with no amplicons being amplified from other closely related trematodes, and the minimum amount of DNA detectable was 0.05 ng. This approach is inexpensive, easy to perform and the whole detection process can be completed within 4h. Examination of 81 S. japonicum samples from SW China's Yunnan and Sichuan provinces, and 264 samples from the lower Yangtze provinces (Hubei, Jiangsu, Jiangxi, Anhui and Hunan) and from Zhejiang validated the value of the specific PCR assay and proved its reliability. These findings indicate that the specific PCR assay would provide a useful tool for the epidemiological surveillance and for tracing the source of S. japonicum infection in humans and animals in China.
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Affiliation(s)
- Guang-Hui Zhao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China
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Ziegelbauer K, Speich B, Mäusezahl D, Bos R, Keiser J, Utzinger J. Effect of sanitation on soil-transmitted helminth infection: systematic review and meta-analysis. PLoS Med 2012; 9:e1001162. [PMID: 22291577 PMCID: PMC3265535 DOI: 10.1371/journal.pmed.1001162] [Citation(s) in RCA: 334] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 12/09/2011] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND In countries of high endemicity of the soil-transmitted helminth parasites Ascaris lumbricoides, Trichuris trichiura, and hookworm, preventive chemotherapy (i.e., repeated administration of anthelmintic drugs to at-risk populations) is the main strategy to control morbidity. However, rapid reinfection of humans occurs after successful deworming, and therefore effective preventive measures are required to achieve public health goals with optimal efficiency and sustainability. METHODS AND FINDINGS We conducted a systematic review and meta-analysis to assess the effect of sanitation (i.e., access and use of facilities for the safe disposal of human urine and feces) on infection with soil-transmitted helminths. PubMed, Embase, ISI Web of Science, and the World Health Organization Library Database were searched without language restrictions and year of publication (search performed until December 31, 2010). Bibliographies of identified articles were hand-searched. All types of studies reporting data on sanitation availability (i.e., having access at own household or living in close proximity to sanitation facility), or usage, and soil-transmitted helminth infections at the individual level were considered. Reported odds ratios (ORs) of the protective effect of sanitation on soil-transmitted helminth infections were extracted from the papers or calculated from reported numbers. The quality of published studies was assessed with a panel of criteria developed by the authors. Random effects meta-analyses were used to account for observed heterogeneity. Thirty-six publications, consisting of 39 datasets, met our inclusion criteria. Availability of sanitation facilities was associated with significant protection against infection with soil-transmitted helminths (OR = 0.46 to 0.58). Regarding the use of sanitation, ORs of 0.54 (95% confidence interval [CI] 0.28-1.02), 0.63 (95% CI 0.37-1.05), and 0.78 (95% CI 0.60-1.00) were determined for T. trichiura, hookworm, and A. lumbricoides, respectively. The overall ORs, combining sanitation availability and use, were 0.51 (95% CI 0.44-0.61) for the three soil-transmitted helminths combined, 0.54 (95% CI 0.43-0.69) for A. lumbricoides, 0.58 (95% CI 0.45-0.75) for T. trichiura, and 0.60 (95% CI 0.48-0.75) for hookworm. CONCLUSIONS Despite a number of limitations (e.g., most studies used a cross-sectional design and were of low quality, with potential biases and considerable heterogeneity), our results reveal that sanitation is associated with a reduced risk of transmission of helminthiases to humans. Access to improved sanitation should be prioritized alongside preventive chemotherapy and health education to achieve a durable reduction of the burden of helminthiases.
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Affiliation(s)
- Kathrin Ziegelbauer
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Benjamin Speich
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Daniel Mäusezahl
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Robert Bos
- Department of Public Health and Environment, World Health Organization, Geneva, Switzerland
| | - Jennifer Keiser
- University of Basel, Basel, Switzerland
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel Switzerland
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Utzinger J, N’Goran EK, Caffrey CR, Keiser J. From innovation to application: social-ecological context, diagnostics, drugs and integrated control of schistosomiasis. Acta Trop 2011; 120 Suppl 1:S121-37. [PMID: 20831855 DOI: 10.1016/j.actatropica.2010.08.020] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/29/2010] [Accepted: 08/30/2010] [Indexed: 12/11/2022]
Abstract
Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs.
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Ng NY, Ruger JP. Global Health Governance at a Crossroads. GLOBAL HEALTH GOVERNANCE : THE SCHOLARLY JOURNAL FOR THE NEW HEALTH SECURITY PARADIGM 2011; 3:1-37. [PMID: 24729828 PMCID: PMC3983705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This review takes stock of the global health governance (GHG) literature. We address the transition from international health governance (IHG) to global health governance, identify major actors, and explain some challenges and successes in GHG. We analyze the framing of health as national security, human security, human rights, and global public good, and the implications of these various frames. We also establish and examine from the literature GHG's major themes and issues, which include: 1) persistent GHG problems; 2) different approaches to tackling health challenges (vertical, horizontal, and diagonal); 3) health's multisectoral connections; 4) neoliberalism and the global economy; 5) the framing of health (e.g. as a security issue, as a foreign policy issue, as a human rights issue, and as a global public good); 6) global health inequalities; 7) local and country ownership and capacity; 8) international law in GHG; and 9) research gaps in GHG. We find that decades-old challenges in GHG persist and GHG needs a new way forward. A framework called shared health governance offers promise.
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Affiliation(s)
- Nora Y Ng
- Research Assistant for Dr. Ruger at the Yale University School of Public Health
| | - Jennifer Prah Ruger
- Associate Professor at Yale University Schools of Medicine, Public Health and Law (Adjunct) and Graduate School of Arts and Sciences
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Proportion of circulating chicken heterophils and CXCLi2 expression in response to Salmonella enteritidis are affected by genetic line and immune modulating diet. Vet Immunol Immunopathol 2011; 140:323-8. [DOI: 10.1016/j.vetimm.2011.01.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Revised: 01/04/2011] [Accepted: 01/05/2011] [Indexed: 11/21/2022]
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MacDonald LH, Pathak G, Singer B, Jaffé PR. An Integrated Approach to Address Endemic Fluorosis in Jharkhand, India. ACTA ACUST UNITED AC 2011. [DOI: 10.4236/jwarp.2011.37056] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Acka CA, Raso G, N'Goran EK, Tschannen AB, Bogoch II, Séraphin E, Tanner M, Obrist B, Utzinger J. Parasitic worms: knowledge, attitudes, and practices in Western Côte d'Ivoire with implications for integrated control. PLoS Negl Trop Dis 2010; 4:e910. [PMID: 21200423 PMCID: PMC3006135 DOI: 10.1371/journal.pntd.0000910] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 11/10/2010] [Indexed: 11/23/2022] Open
Abstract
Background In the developing world where parasitic worm infections are pervasive, preventive chemotherapy is the key strategy for morbidity control. However, local knowledge, attitudes, and practices (KAP) of parasitic worms are poorly understood, although such information is required for prevention and sustainable control. Methods We carried out KAP surveys in two rural communities of Côte d'Ivoire that were subjected to school-based and community-based research and control activities. We used qualitative and quantitative methods. The former included observations, in-depth interviews with key informants, and focus group discussions with school children and adults. Quantitative methods consisted of a structured questionnaire administered to household heads. Principal Findings Access to clean water was lacking in both communities and only a quarter of the households had functioning latrines. There was a better understanding of soil-transmitted helminthiasis than intestinal schistosomiasis, but community-based rather than school-based interventions appeared to improve knowledge of schistosomiasis. In the villages with community-based interventions, three-quarters of household interviewees knew about intestinal schistosomiasis compared to 14% in the village where school-based interventions were implemented (P<0.001). Whereas two-thirds of respondents from the community-based intervention village indicated that the research and control project was the main source of information, only a quarter of the respondents cited the project as the main source. Conclusions/Significance Preventive chemotherapy targeting school-aged children has limitations, as older population segments are neglected, and hence lack knowledge about how to prevent and control parasitic worm infections. Improved access to clean water and sanitation is necessary, along with health education to make a durable impact against helminth infections. There is a need to better understand communities' knowledge, attitudes, and practices (KAP) of neglected tropical diseases to improve prevention and control efforts. We studied the socio-cultural aspects of parasitic worm infections in two villages (Mélapleu and Zouatta II) of western Côte d'Ivoire, where research and control activities have been implemented. Zouatta II was exposed to a community-based approach, while school-based interventions were implemented in Mélapleu. KAP surveys were carried out using qualitative and quantitative methods. Although there was some knowledge of parasitic worm infections in both villages, we found important differences between the two villages regarding intestinal schistosomiasis: there was a better understanding of this disease in Zouatta II. However, even the community-based research and control efforts implemented in Zouatta II were ineffective in transforming the information conveyed into preventive behavior related to water contact. Our results suggest that KAP of parasitic worm infections conveyed by research and control activities targeting only school-aged children have shortcomings as older population groups are left out. Hence, for effective control of parasitic worms, children and adults must be educated and interventions should include access to deworming drugs, clean water and sanitation.
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Affiliation(s)
- Cinthia A. Acka
- Unité de Formation et de Recherche (UFR) Sciences Sociales, Université de Cocody-Abidjan, Abidjan, Côte d'Ivoire
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Giovanna Raso
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Eliézer K. N'Goran
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
- Unité de Formation et de Recherche (UFR) Biosciences, Université de Cocody-Abidjan, Abidjan, Côte d'Ivoire
| | - Andres B. Tschannen
- Département Environnement et Santé, Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Isaac I. Bogoch
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Essane Séraphin
- Unité de Formation et de Recherche (UFR) Sciences Sociales, Université de Cocody-Abidjan, Abidjan, Côte d'Ivoire
| | - Marcel Tanner
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Brigit Obrist
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Institute of Social Anthropology, University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Lin Y, Heffernan C. Accessible and inexpensive tools for global HPAI surveillance: A mobile-phone based system. Prev Vet Med 2010; 98:209-14. [PMID: 21167614 DOI: 10.1016/j.prevetmed.2010.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 07/04/2010] [Accepted: 10/05/2010] [Indexed: 11/24/2022]
Abstract
Highly pathogenic avian influenza (HPAI) disproportionately impacts poor livestock keepers in southern countries. Although the estimated cost of the disease in the billions, response to the epidemic remains fragmented and information channels slow. Given the continuing threat of outbreaks, and what appears to be the politicisation of outbreak reporting, new tools are needed to enforce transparency in stakeholder communication. In response to this need, we created a mobile-phone based surveillance system to aid critical information transfer among policy makers, practitioners and the poor themselves. The tool operates at the local, national and global levels and further links decision-makers to international databases.
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Affiliation(s)
- Yibo Lin
- The Livestock Development Group, School of Agriculture, Policy and Development, University of Reading, Earley Gate, Whiteknights Road, PO Box 237, Reading RG6 6AT, UK
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Utzinger J, Bergquist R, Olveda R, Zhou XN. Important helminth infections in Southeast Asia diversity, potential for control and prospects for elimination. ADVANCES IN PARASITOLOGY 2010; 72:1-30. [PMID: 20624526 DOI: 10.1016/s0065-308x(10)72001-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Besides the 'big three'-HIV/AIDS, malaria and tuberculosis-there are a host of diseases that, by comparison, are truly neglected. These so-called neglected tropical diseases (NTDs), many of which caused by helminths, are intimately linked with poverty and are rampant where housing is poor; access to clean water and adequate sanitation is lacking; hygiene and nutrition is substandard and populations are marginalized and vulnerable. More than a billion people are affected by NTDs, mainly in remote rural and deprived urban settings of the developing world. An overview of papers published in two special thematic volumes of the Advances in Parasitology is provided here under the umbrella of current status of research and control of important helminth infections. A total of 25 comprehensive reviews are presented, which summarise the latest available data pertaining to the diagnosis, epidemiology, pathogenesis, prevention, treatment, control and eventual elimination of NTDs in Southeast Asia and neighbourhood countries. The focus of the first volume provides the current regional status of schistosomiasis, lymphatic filariasis, food-borne trematodiases, echinococcosis and cysticercosis/taeniasis, less common parasitic diseases that can cause epidemic outbreaks and helminth infections affecting the central nervous system. The second volume deals with the tools and strategies for control, including diagnostics, drugs, vaccines and cutting-edge basic research (e.g. the '-omics' sciences). Moreover, cross-cutting themes such as multiparasitism, social sciences, capacity strengthening, geospatial health technologies, health metrics and modelling the potential impact of climate change on helminthic diseases are discussed. Hopefully, these two volumes will become useful for researchers and, most importantly, disease control managers for integrated and sustainable control, rigorous monitoring and eventual elimination of NTDs in Southeast Asia and elsewhere.
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Affiliation(s)
- Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
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Steinmann P, Utzinger J, Du ZW, Zhou XN. Multiparasitism a neglected reality on global, regional and local scale. ADVANCES IN PARASITOLOGY 2010; 73:21-50. [PMID: 20627138 DOI: 10.1016/s0065-308x(10)73002-5] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review focuses on the issue of multiparasitism, with a special emphasis on its characteristics, its extent in eastern Asia and its significance for infectious disease control. Multiparasitism is pervasive among socially and economically disadvantaged or marginalised communities, particularly in tropical and subtropical areas. Intestinal parasites are the most numerous group, but an array of parasites is located elsewhere than in the human gastrointestinal tract. Although multiparasitism has been recognised for decades, in-depth studies are rare, and its public health and economic implications have yet to be fully elucidated. The assessment of multiparasitism is hampered by a lack of sensitive broad-spectrum diagnostic tools and the need to collect multiple biological samples for detailed appraisal. Non-specific symptoms and mainly subtle effects complicate the appreciation of its influence on cognitive and physical development, health, economic productivity and general well-being. Multiparasitism has been reported from virtually every eastern Asian country, and studies regarding the extent of multiparasitism and its effects on child health have been implemented in the region. However, new research is needed, as no comprehensive evaluations of multiparasitism in eastern Asia could be identified. Two case studies pertaining to multiparasitism at the local and regional scale are presented. Multiparasitism was rampant in an ethnic minority village in southern People's Republic of China where the challenges associated with its thorough evaluation are illustrated. The results from a cross-sectional survey covering 35 villages highlight the significance of its evaluation for the design of locally adapted and sustainable parasite control and poverty alleviation programmes. We conclude by listing a set of research needs for future investigations.
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Affiliation(s)
- Peter Steinmann
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
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