1
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Thorstenberg ML, Martins MDA, Oliveira NF, Monteiro MMLV, Santos GC, Pereira HG, Savio LEB, Coutinho-Silva R, Silva CLM. Altered purinergic P2X7 and A 2B receptors signaling limits macrophage-mediated host defense in schistosomiasis. Biomed J 2024:100713. [PMID: 38442854 DOI: 10.1016/j.bj.2024.100713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 01/05/2024] [Accepted: 02/25/2024] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND The occurrence of co-infections during schistosomiasis, a neglected tropical disease, with other parasites have been reported suggesting an impaired host immune defense. Macrophage purinergic P2X7 receptor (P2X7R) play an important role against intracellular pathogens. Therefore, we investigated the P2X7R-mediated phagocytosis and killing capacity of Leishmania amazonensis by macrophages during schistosomiasis in vitro and in vivo. METHODS Swiss and C57BL/6 (Wild type) and P2X7R-/- were randomized in two groups: control (uninfected) and Schistosoma mansoni-infected. Alternatively, control Swiss and S. mansoni-infected mice were also infected with L. amazonensis. RESULTS The pre-treatment of macrophages with the P2X7R antagonist (A74003) or TGF-β reduced the phagocytosis index, mimicking the phenotype of cells from S. mansoni-infected mice and P2X7R-/- mice. Apyrase also reduced the phagocytosis index corroborating the role of ATP to macrophage activation. Moreover, l-arginine-nitric oxide pathway was compromised, which could explain the reduced killing capacity in response to ATP in vitro and in vivo. We found an increased extracellular nucleotide (ATP, ADP and AMP) hydrolysis along with an increased frequency of F4/80+ CD39+ macrophages from the S. mansoni-infected group. Moreover, the content of adenosine in the cell supernatant was higher in the S. mansoni-infected group in relation to controls. Schistosomiasis also increased the expression of macrophage adenosine A2BR. In good accordance, both ADA and the selective A2BR antagonist restored the phagocytosis index of macrophages from S. mansoni-infected group. CONCLUSIONS Altogether, the altered P2X7R and A2BR signaling limits the role of macrophages to host defense against L. amazonensis during schistosomiasis, potentially contributing to the pathophysiology and clinically relevant co-infections.
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Affiliation(s)
- Maria Luiza Thorstenberg
- Laboratory of Biochemical and Molecular Pharmacology, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
| | - Monique Daiane Andrade Martins
- Laboratory of Immunophysiology, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
| | - Nathália Ferreira Oliveira
- Laboratory of Biochemical and Molecular Pharmacology, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
| | - Matheus Macedo L V Monteiro
- Laboratory of Biochemical and Molecular Pharmacology, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil
| | - GustavoR C Santos
- Brazilian Doping Control Laboratory (LBCD - LADETEC / IQ), Universidade Federal do Rio de Janeiro, Brazil
| | | | - Luiz Eduardo Baggio Savio
- Laboratory of Immunophysiology, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
| | - Robson Coutinho-Silva
- Laboratory of Immunophysiology, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
| | - Claudia Lucia Martins Silva
- Laboratory of Biochemical and Molecular Pharmacology, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Brazil.
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2
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Camacho-Alvarez I, Chavez-Mamani EM, Philippe G, Luizaga-López JM, Torrico MC, Gétaz L, Jacobs F. A simple parasitological technique to increase detection of Strongyloides stercoralis in Bolivian primary health care system. BMC PRIMARY CARE 2022; 23:284. [PMID: 36396996 PMCID: PMC9673357 DOI: 10.1186/s12875-022-01888-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Strongyloides stercoralis is widespread; however, there is limited information on its prevalence owing to laboratory underestimation and low clinical manifestations. The Baermann method and agar culture stand out among the parasitological techniques. Strongyloides stercoralis is present in Bolivia, but its prevalence in children remains unknown. The objective of this study was to estimate the applicability of simple parasitological techniques to increase the detection of this parasite in children living in the tropics. METHODS This cross-sectional study was conducted in a tropical village in Cochabamba, Bolivia. Participants were 304 children aged 5 - 12 years who provided stool samples for different parasitological analyses (direct examination, Ritchie, Baermann, and Dancescu techniques), and their parents provided informed consent. RESULTS Up to 64.8% of pathogenic parasites were detected using the modified Ritchie method. The Baermann technique identified 17.8% of Strongyloides stercoralis cases, and a high sensitivity with respect to the Baermann technique was only for the Dancescu technique (75.9%) that is also specific for Strongyloides stercoralis, followed by 66.7% for the modified Ritchie technique, which is used in second-line care. DISCUSSION The Baermann technique is the best parasitological option for improving Strongyloides stercoralis diagnosis in the first-line care of the Primary Health Care System. A particular cycle of reinfection, combined with the environment and some other risk factors are related with persistence. Control is difficult without a proper diagnosis, and the Baermann technique is an approach to the solution. We conclude that with a high suspicion of the presence of Strongyloides stercoralis, the use of the Baermann technique is strongly recommended as support for direct examination in primary health care systems especially in tropical areas.
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Affiliation(s)
- Ivana Camacho-Alvarez
- Medical Sciences Université Libre de Bruxelles (Belgium); Public Health and Epidemiology, University of San Simón (Bolivia), Cochabamba, Bolivia.
| | - Elia M Chavez-Mamani
- Biomedical and Social Research Institute, Medicine Faculty, University of San Simón, Cochabamba, Bolivia
| | - Goyens Philippe
- Nutrition and Metabolism Unit, Department of Pediatrics, Hôpital Universitaire des Enfants Reine Fabiola HUDERF, Brussels, Belgium
| | - Jenny M Luizaga-López
- Biomedical and Social Research Institute, University of San Simón, Cochabamba, Bolivia
| | - Mary Cruz Torrico
- Medical Research Laboratory, Parasitology, Medicine Faculty, University of San Simón, Cochabamba, Bolivia
| | - Laurent Gétaz
- Division of Tropical and Humanitarian Medicine, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Frédérique Jacobs
- Infectious Diseases Department at Université Libre de Bruxelles, CUB-Erasme, Brussels, Belgium
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3
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Avila HG, Risso MG, Cabrera M, Ruybal P, Repetto SA, Butti MJ, Trangoni MD, Santillán G, Pérez VM, Periago MV. Development of a New LAMP Assay for the Detection of Ancylostoma caninum DNA (Copro-LAMPAc) in Dog Fecal Samples. Front Vet Sci 2021; 8:770508. [PMID: 34869740 PMCID: PMC8633310 DOI: 10.3389/fvets.2021.770508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 10/13/2021] [Indexed: 01/17/2023] Open
Abstract
Ancylostoma caninum is a zoonotic nematode which is able to affect animals and humans. Diagnosis in the definitive host and environmental detection are key to prevent its dissemination and achieve control. Herein, a new coprological LAMP method for the detection of A. caninum (Copro-LAMPAc) DNA was developed. DNA extraction was performed using a low-cost method and a fragment of the cox-1 gene was used for primer design. The analytical sensitivity, evaluated with serial dilutions of genomic DNA from A. caninum adult worms, was 100 fg. A specificity of 100% was obtained using genomic DNA from the host and other pathogens. The Copro-LAMPAc was evaluated using environmental canine fecal samples. When compared with gold standard optical microscopy in epidemiological studies, it proved to be more sensitive. This new LAMP assay can provide an alternative protocol for screening and identification of A. caninum for epidemiological studies in endemic areas.
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Affiliation(s)
- Héctor Gabriel Avila
- Laboratorio Provincial de Zoonosis de San Juan, Facultad de Ciencias Veterinarias, Facultad de Ciencias Químicas y Tecnológicas, Universidad Católica de Cuyo, San Juan, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Marikena Guadalupe Risso
- Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Microbiología y Parasitología Médica, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marta Cabrera
- Departamento de Parasitología, Instituto Nacional de Enfermedades Infecciosas, Administración Nacional de Laboratorios e Institutos de Salud (ANLIS) "Dr. Carlos G. Malbrán", Buenos Aires, Argentina
| | - Paula Ruybal
- Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Microbiología y Parasitología Médica, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Silvia Analía Repetto
- Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Investigaciones en Microbiología y Parasitología Médica, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Buenos Aires, Argentina.,División Infectología, Hospital de Clínicas "José de San Martín", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marcos Javier Butti
- Laboratorio de Parasitosis Humanas y Zoonosis Parasitarias, Cátedra de Parasitología Comparada, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, La Plata, Argentina
| | - Marcos David Trangoni
- Laboratorio de Brucella, Campylobacter y Microbiota del rumen, Instituto de Biotecnología/Instituto de Agrobiotecnología y Biología Molecular, Unidades Ejecutoras de Doble Dependencia (UEDD) INTA-CONICET, Investigación en Ciencias Veterinarias y Agronómicas (CICVyA), Centro Nacional de Investigaciones Agropecuarias (CNIA), INTA Castelar, Buenos Aires, Argentina
| | - Graciela Santillán
- Departamento de Parasitología, Instituto Nacional de Enfermedades Infecciosas, Administración Nacional de Laboratorios e Institutos de Salud (ANLIS) "Dr. Carlos G. Malbrán", Buenos Aires, Argentina
| | - Verónica Mirtha Pérez
- Laboratorio Provincial de Zoonosis de San Juan, Facultad de Ciencias Veterinarias, Facultad de Ciencias Químicas y Tecnológicas, Universidad Católica de Cuyo, San Juan, Argentina.,Sección de Rabia y Zoonosis, Dirección de Epidemiología, Ministerio de Salud Pública de San Juan, San Juan, Argentina
| | - María Victoria Periago
- Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina.,Fundación Mundo Sano, Buenos Aires, Argentina
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4
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Ajendra J. Lessons in type 2 immunity: Neutrophils in Helminth infections. Semin Immunol 2021; 53:101531. [PMID: 34836773 DOI: 10.1016/j.smim.2021.101531] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 12/20/2022]
Abstract
Neutrophils constitute the body's first line of defense against invading pathogens. Equipped with a large array of tools, these immune cells are highly efficient in eliminating bacterial and viral infections, yet their activity can at the same time be detrimental to the host itself - this is the broad consensus on these granulocytes. However, the last decade has proven that neutrophils are a much more sophisticated cell type with unexpected and underappreciated functions in health and disease. In this review, we look at the latest discoveries in neutrophil biology with a focus on their role during the hallmark setting of type 2 immunity - helminth infection. We discuss the involvement of neutrophils in various helminth infection models and summarize the latest findings regarding neutrophil regulation and effector function. We will show that neutrophils have much more to offer than previously thought and while studies of neutrophils in helminth infections are still in its infancy, recent discoveries highlight more than ever that these cells are a key cog of the immune system, even during type 2 responses.
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Affiliation(s)
- Jesuthas Ajendra
- Lydia Becker Institute for Immunology & Infection, Faculty of Biology, Medicine & Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK; Wellcome Centre for Cell-Matrix Research, Manchester, M13 9PT, UK.
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5
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Jayawardene KLTD, Palombo EA, Boag PR. Natural Products Are a Promising Source for Anthelmintic Drug Discovery. Biomolecules 2021; 11:1457. [PMID: 34680090 PMCID: PMC8533416 DOI: 10.3390/biom11101457] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/23/2021] [Accepted: 09/28/2021] [Indexed: 12/23/2022] Open
Abstract
Parasitic nematodes infect almost all forms of life. In the human context, parasites are one of the major causative factors for physical and intellectual growth retardation in the developing world. In the agricultural setting, parasites have a great economic impact through a reduction in livestock performance or control cost. The main method of controlling these devastating conditions is the use of anthelmintic drugs. Unfortunately, there are only a few anthelmintic drug classes available in the market and significant resistance has developed in most of the parasitic species of livestock. Therefore, development of new anthelmintics with different modes of action is critical for sustainable parasitic control in the future. The drug development pipeline is broadly limited to two types of molecules, namely synthetic compounds and natural plant products. Compared to synthetic compounds, natural products are highly diverse, and many have historically proven valuable in folk medicine to treat various gastrointestinal ailments. This review focus on the use of traditional knowledge-based plant extracts in the development of new therapeutic leads, the approaches used as screening techniques, and common bottlenecks and opportunities in plant-based anthelmintic drug discovery.
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Affiliation(s)
- K. L. T. Dilrukshi Jayawardene
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia;
- Development and Stem Cells Program, Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC 3800, Australia
| | - Enzo A. Palombo
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, VIC 3122, Australia
| | - Peter R. Boag
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia;
- Development and Stem Cells Program, Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC 3800, Australia
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6
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Turner HC, Archer RA, Downey LE, Isaranuwatchai W, Chalkidou K, Jit M, Teerawattananon Y. An Introduction to the Main Types of Economic Evaluations Used for Informing Priority Setting and Resource Allocation in Healthcare: Key Features, Uses, and Limitations. Front Public Health 2021; 9:722927. [PMID: 34513790 PMCID: PMC8424074 DOI: 10.3389/fpubh.2021.722927] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 07/31/2021] [Indexed: 11/13/2022] Open
Abstract
Economic evidence is increasingly being used for informing health policies. However, the underlining principles of health economic analyses are not always fully understood by non-health economists, and inappropriate types of analyses, as well as inconsistent methodologies, may be being used for informing health policy decisions. In addition, there is a lack of open access information and methodological guidance targeted to public health professionals, particularly those based in low- and middle-income country (LMIC) settings. The objective of this review is to provide a comprehensive and accessible introduction to economic evaluations for public health professionals with a focus on LMIC settings. We cover the main principles underlining the most common types of full economic evaluations used in healthcare decision making in the context of priority setting (namely cost-effectiveness/cost-utility analyses, cost-benefit analyses), and outline their key features, strengths and weaknesses. It is envisioned that this will help those conducting such analyses, as well as stakeholders that need to interpret their output, gain a greater understanding of these methods and help them select/distinguish between the different approaches. In particular, we highlight the need for greater awareness of the methods used to place a monetary value on the health benefits of interventions, and the potential for such estimates to be misinterpreted. Specifically, the economic benefits reported are typically an approximation, summarising the health benefits experienced by a population monetarily in terms of individual preferences or potential productivity gains, rather than actual realisable or fiscal monetary benefits to payers or society.
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Affiliation(s)
- Hugo C Turner
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Rachel A Archer
- Health Intervention and Technology Assessment Program, Ministry of Public Health, Nonthaburi, Thailand
| | - Laura E Downey
- School of Public Health, Imperial College London, London, United Kingdom
| | - Wanrudee Isaranuwatchai
- Health Intervention and Technology Assessment Program, Ministry of Public Health, Nonthaburi, Thailand.,Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada
| | - Kalipso Chalkidou
- School of Public Health, Imperial College London, London, United Kingdom
| | - Mark Jit
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Modelling and Economics Unit, Public Health England, London, United Kingdom
| | - Yot Teerawattananon
- Health Intervention and Technology Assessment Program, Ministry of Public Health, Nonthaburi, Thailand.,Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
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7
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Turner HC, Stolk WA, Solomon AW, King JD, Montresor A, Molyneux DH, Toor J. Are current preventive chemotherapy strategies for controlling and eliminating neglected tropical diseases cost-effective? BMJ Glob Health 2021; 6:bmjgh-2021-005456. [PMID: 34385158 PMCID: PMC8362715 DOI: 10.1136/bmjgh-2021-005456] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 02/07/2023] Open
Abstract
Neglected tropical diseases (NTDs) remain a significant cause of morbidity and mortality in many low-income and middle-income countries. Several NTDs, namely lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiases (STH) and trachoma, are predominantly controlled by preventive chemotherapy (or mass drug administration), following recommendations set by the WHO. Over one billion people are now treated for NTDs with this strategy per year. However, further investment and increased domestic healthcare spending are urgently needed to continue these programmes. Consequently, it is vital that the cost-effectiveness of preventive chemotherapy is understood. We analyse the current estimates on the cost per disability-adjusted life year (DALY) of the preventive chemotherapy strategies predominantly used for these diseases and identify key evidence gaps that require further research. Overall, the reported estimates show that preventive chemotherapy is generally cost-effective, supporting WHO recommendations. More specifically, the cost per DALY averted estimates relating to community-wide preventive chemotherapy for lymphatic filariasis and onchocerciasis were particularly favourable when compared with other public health interventions. Cost per DALY averted estimates of school-based preventive chemotherapy for schistosomiasis and STH were also generally favourable but more variable. Notably, the broader socioeconomic benefits are likely not being fully captured by the DALYs averted metric. No estimates of cost per DALY averted relating to community-wide mass antibiotic treatment for trachoma were found, highlighting the need for further research. These findings are important for informing global health policy and support the need for continuing NTD control and elimination efforts.
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Affiliation(s)
- Hugo C Turner
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK .,Oxford University Clinical Research Unit, Wellcome Africa Asia Programme, Ho Chi Minh City, Vietnam.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Wilma A Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Jonathan D King
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - David H Molyneux
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Jaspreet Toor
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK,Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
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8
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Oliveira NF, Silva CLM. Unveiling the Potential of Purinergic Signaling in Schistosomiasis Treatment. Curr Top Med Chem 2021; 21:193-204. [PMID: 32972342 DOI: 10.2174/1568026620666200924115113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/15/2020] [Accepted: 08/24/2020] [Indexed: 11/22/2022]
Abstract
Schistosomiasis is a neglected tropical disease. It is related to long-lasting granulomatous fibrosis and inflammation of target organs, and current sub-optimal pharmacological treatment creates global public health concerns. Intravascular worms and eggs release antigens and extracellular vesicles that target host endothelial cells, modulate the immune system, and stimulate the release of damageassociated molecular patterns (DAMPs). ATP, one of the most studied DAMPs, triggers a cascade of autocrine and paracrine actions through purinergic P2X and P2Y receptors, which are shaped by ectonucleotidases (CD39). Both P2 receptor families, and in particular P2Y1, P2Y2, P2Y12, and P2X7 receptors, have been attracting increasing interest in several inflammatory diseases and drug development. Current data obtained from the murine model unveiled a CD39-ADP-P2Y1/P2Y12 receptors signaling pathway linked to the liver and mesenteric exacerbations of schistosomal inflammation. Therefore, we proposed that members of this purinergic signaling could be putative pharmacological targets to reduce schistosomal morbidity.
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Affiliation(s)
- Nathália Ferreira Oliveira
- Laboratory of Molecular and Biochemical Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Claudia Lucia Martins Silva
- Laboratory of Molecular and Biochemical Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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9
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Roriz SJ, Pereira TA, Vaz de Melo Trindade G, Caporali JFDM, Lambertucci JR. Quality of Life Assessment Among Patients Living With Hepatosplenic Schistosomiasis and Schistosomal Myeloradiculopathy. Front Med (Lausanne) 2021; 8:629484. [PMID: 34141713 PMCID: PMC8203918 DOI: 10.3389/fmed.2021.629484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 05/10/2021] [Indexed: 12/12/2022] Open
Abstract
Schistosomiasis is a major public health problem in tropical areas of the world. Health-related quality of life (HRQOL) measurement is being widely used to evaluate the impact of a disease or treatment in several aspects of daily life. However, few studies evaluated the impact of severe forms of schistosomiasis on HRQOL of affected individuals and compared them to healthy controls with a similar socio-demographic background. Our aims were to evaluate the HRQOL in patients with hepatosplenic schistosomiasis (HS) and schistosomal myeloradiculopathy (SMR) and healthy volunteers (HV) and determine if clinical complications of the disease are associated with HRQOL scores. We interviewed and evaluated the HRQOL in 49 patients with HS, 22 patients with SMR, and 26 HV from an outpatient clinic of the Federal University of Minas Gerais University Hospital using the WHOQOL-BREF questionnaire. SMR and HS patients had a significantly lower overall quality of life score when comparing with the HV control group (p = 0.003 and p = 0.005, respectively). Multivariate ordinal regression model adjusted for sex, age, and educational level indicated that HS and SMR patients have three and five times more chances of having a lower quality of life than healthy volunteers (Odds Ratio 3.13 and 5.04, respectively). There was no association between complications of HS disease and quality of life scores. In contrast, worse quality of life was observed in SMR patients that presented back or leg pain, leg paresthesia, and bladder dysfunction. In conclusion, HS and SMR significantly impact the overall quality of life of the affected individuals, reinforcing the importance of efforts to control and eradicate this debilitating disease and suggesting that multidisciplinary clinical management of schistosomiasis patients would be more appropriate and could potentially improve patient's quality of life.
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Affiliation(s)
- Silvana Júnia Roriz
- Graduate Program in Infectious Diseases and Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Thiago Almeida Pereira
- Graduate Program in Infectious Diseases and Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.,Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Guilherme Vaz de Melo Trindade
- Graduate Program in Infectious Diseases and Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.,Physiology, School of Medicine, National University of Ireland, Galway, Galway, Ireland
| | - Júlia Fonseca de Morais Caporali
- Graduate Program in Infectious Diseases and Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.,Department of Internal Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - José Roberto Lambertucci
- Graduate Program in Infectious Diseases and Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.,Department of Internal Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
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10
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Vanhamme L, Souopgui J, Ghogomu S, Ngale Njume F. The Functional Parasitic Worm Secretome: Mapping the Place of Onchocerca volvulus Excretory Secretory Products. Pathogens 2020; 9:pathogens9110975. [PMID: 33238479 PMCID: PMC7709020 DOI: 10.3390/pathogens9110975] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 01/15/2023] Open
Abstract
Nematodes constitute a very successful phylum, especially in terms of parasitism. Inside their mammalian hosts, parasitic nematodes mainly dwell in the digestive tract (geohelminths) or in the vascular system (filariae). One of their main characteristics is their long sojourn inside the body where they are accessible to the immune system. Several strategies are used by parasites in order to counteract the immune attacks. One of them is the expression of molecules interfering with the function of the immune system. Excretory-secretory products (ESPs) pertain to this category. This is, however, not their only biological function, as they seem also involved in other mechanisms such as pathogenicity or parasitic cycle (molting, for example). We will mainly focus on filariae ESPs with an emphasis on data available regarding Onchocerca volvulus, but we will also refer to a few relevant/illustrative examples related to other worm categories when necessary (geohelminth nematodes, trematodes or cestodes). We first present Onchocerca volvulus, mainly focusing on the aspects of this organism that seem relevant when it comes to ESPs: life cycle, manifestations of the sickness, immunosuppression, diagnosis and treatment. We then elaborate on the function and use of ESPs in these aspects.
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Affiliation(s)
- Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Rue des Professeurs Jeener et Brachet 12, 6041 Gosselies, Belgium; (J.S.); (F.N.N.)
- Correspondence:
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Rue des Professeurs Jeener et Brachet 12, 6041 Gosselies, Belgium; (J.S.); (F.N.N.)
| | - Stephen Ghogomu
- Molecular and Cell Biology Laboratory, Biotechnology Unit, University of Buea, Buea P.O Box 63, Cameroon;
| | - Ferdinand Ngale Njume
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Rue des Professeurs Jeener et Brachet 12, 6041 Gosselies, Belgium; (J.S.); (F.N.N.)
- Molecular and Cell Biology Laboratory, Biotechnology Unit, University of Buea, Buea P.O Box 63, Cameroon;
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11
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Adisakwattana P, Yoonuan T, Phuphisut O, Poodeepiyasawat A, Homsuwan N, Gordon CA, McManus DP, Atkinson LE, Mousley A, Gobert GN. Clinical helminthiases in Thailand border regions show elevated prevalence levels using qPCR diagnostics combined with traditional microscopic methods. Parasit Vectors 2020; 13:416. [PMID: 32787935 PMCID: PMC7425172 DOI: 10.1186/s13071-020-04290-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/05/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Under-regulated national borders in Southeast Asia represent potential regions for enhanced parasitic helminth transmission and present barriers to helminthiasis disease control. METHODS Three Thailand border regions close to Myanmar, Laos and Cambodia were surveyed for clinical parasitic helminth disease. In-field microscopy was performed on stools from 567 individuals. Sub-samples were transported to Bangkok for molecular analysis comprising three multiplex qPCR assays. RESULTS The overall helminth infection prevalence was 17.99% as assessed by Kato-Katz and 24.51% by qPCR. The combined prevalence of the two methods was 28.57%; the most predominant species detected were Opisthorchis viverrini (18.34%), hookworm (6.88%; Ancylostoma spp. and Necator americanus), Ascaris lumbricoides (2.29%) and Trichuris trichiura (1.76%). CONCLUSIONS These data demonstrate the value of molecular diagnostics for determining more precise prevalence levels of helminthiases in Southeast Asia. Availability of such accurate prevalence information will help guide future public health initiatives and highlights the need for more rigorous surveillance and timely intervention in these regions.
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Affiliation(s)
- Poom Adisakwattana
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
| | - Tippayarat Yoonuan
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Orawan Phuphisut
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Akkarin Poodeepiyasawat
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Nirundorn Homsuwan
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Catherine A Gordon
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, 4006, Australia
| | - Donald P McManus
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, 4006, Australia
| | - Louise E Atkinson
- School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, UK
| | - Angela Mousley
- School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, UK
| | - Geoffrey N Gobert
- School of Biological Sciences, Queen's University Belfast, Belfast, BT9 5DL, UK.
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12
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Abudho BO, Guyah B, Ondigo BN, Ndombi EM, Ireri E, Carter JM, Riner DK, Kittur N, Karanja DMS, Colley DG. Evaluation of morbidity in Schistosoma mansoni-positive primary and secondary school children after four years of mass drug administration of praziquantel in western Kenya. Infect Dis Poverty 2020; 9:67. [PMID: 32539826 PMCID: PMC7296924 DOI: 10.1186/s40249-020-00690-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/08/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND World Health Organization guidelines recommend preventive chemotherapy with praziquantel to control morbidity due to schistosomiasis. The primary aim of this cross-sectional study was to determine if 4 years of annual mass drug administration (MDA) in primary and secondary schools lowered potential markers of morbidity in infected children 1 year after the final MDA compared to infected children prior to initial MDA intervention. METHODS Between 2012 and 2016 all students in two primary and three secondary schools within three kilometers of Lake Victoria in western Kenya received annual mass praziquantel administration. To evaluate potential changes in morbidity we measured height, weight, mid-upper arm circumference, hemoglobin levels, abdominal ultrasound, and quality of life in children in these schools. This study compared two cross-sectional samples of Schistosoma mansoni egg-positive children: one at baseline and one at year five, 1 year after the fourth annual MDA. Data were analyzed for all ages (6-18 years old) and stratified by primary (6-12 years old) and secondary (12-18 years old) school groups. RESULTS The prevalence of multiple potential morbidity markers did not differ significantly between the egg-positive participants at baseline and those at 5 years by Mann Whitney nonparametric analysis and Fisher's exact test for continuous and categorical data, respectively. There was a small but significantly higher score in school-related quality of life assessment by year five compared to baseline by Mann Whitney analysis (P = 0.048) in 13-18 year olds where malaria-negative. However, anemia was not positively impacted by four annual rounds of MDA, but registered a significant negative outcome. CONCLUSIONS We did not detect differences in morbidity markers measured in a population of those infected or re-infected after multiple MDA. This could have been due to their relative insensitivity or a failure of MDA to prevent morbidity among those who remain infected. High malaria transmission in this area and/or a lack of suitable methods to measure the more subtle functional morbidities caused by schistosomiasis could be a factor. Further research is needed to identify and develop well-defined, easily quantifiable S. mansoni morbidity markers for this age group.
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Affiliation(s)
- Bernard O Abudho
- Centre for Global Health Research (KEMRI-CGHR), Kenya Medical Research Institute, Kisumu, Kenya.
- Department of Biomedical Sciences and Technology, Maseno University, Maseno, Kenya.
| | - Bernard Guyah
- Department of Biomedical Sciences and Technology, Maseno University, Maseno, Kenya
| | - Bartholomew N Ondigo
- Centre for Global Health Research (KEMRI-CGHR), Kenya Medical Research Institute, Kisumu, Kenya
- Department of Biochemistry and Molecular Biology, Egerton University, Nakuru, Kenya
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| | - Eric M Ndombi
- Centre for Global Health Research (KEMRI-CGHR), Kenya Medical Research Institute, Kisumu, Kenya
- Department of Pathology, Kenyatta University, Nairobi, Kenya
| | - Edmund Ireri
- Centre for Clinical Research-Radiology Unit, Kenya Medical Research Institute, Nairobi, Kenya
| | - Jennifer M Carter
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Diana K Riner
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Nupur Kittur
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Diana M S Karanja
- Centre for Global Health Research (KEMRI-CGHR), Kenya Medical Research Institute, Kisumu, Kenya
| | - Daniel G Colley
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
- Department of Microbiology, University of Georgia, Athens, GA, USA
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13
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Zhu HH, Huang JL, Zhu TJ, Zhou CH, Qian MB, Chen YD, Zhou XN. National surveillance on soil-transmitted helminthiasis in the People's Republic of China. Acta Trop 2020; 205:105351. [PMID: 31958411 DOI: 10.1016/j.actatropica.2020.105351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/15/2020] [Accepted: 01/17/2020] [Indexed: 11/18/2022]
Abstract
Soil-transmitted helminths (STHs) are widely distributed and remain a public health problem in the People's Republic of China. Altogether, 301 counties across 30 regions were investigated during the national surveillance on STHs carried out in 2016 based on the modified Kato-Katz thick smear method to examine faecal samples. A total of 305 081 people were investigated with 7 366 (2.4%) found to be infected. The infection rates were the following: hookworm 1.4%, Ascaris lumbricoides 0.8% and Trichuris trichiura 0.5%. Having established that the STHs infection rate is relatively low, it is time to move towards elimination. The national surveillance system is essential for providing basic data and formulation of useful control strategies towards achieving this goal.
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Affiliation(s)
- Hui-Hui Zhu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China
| | - Ji-Lei Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China
| | - Ting-Jun Zhu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China
| | - Chang-Hai Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China
| | - Men-Bao Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China
| | - Ying-Dan Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; 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; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai 200025, China.
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14
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Mutuku MW, Laidemitt MR, Beechler BR, Mwangi IN, Otiato FO, Agola EL, Ochanda H, Kamel B, Mkoji GM, Steinauer ML, Loker ES. A Search for Snail-Related Answers to Explain Differences in Response of Schistosoma mansoni to Praziquantel Treatment among Responding and Persistent Hotspot Villages along the Kenyan Shore of Lake Victoria. Am J Trop Med Hyg 2020; 101:65-77. [PMID: 31162012 PMCID: PMC6609173 DOI: 10.4269/ajtmh.19-0089] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Following a 4-year annual praziquantel (PZQ) treatment campaign, the resulting prevalence of Schistosoma mansoni was seen to differ among individual villages along the Kenyan shore of Lake Victoria. We have investigated possible inherent differences in snail-related aspects of transmission among such 10 villages, including six persistent hotspot (PHS) villages (≤ 30% reduction in prevalence following repeated treatments) located along the west-facing shore of the lake and four PZQ-responding (RESP) villages (> 30% prevalence reduction following repeated treatment) along the Winam Gulf. When taking into account all sampling sites, times, and water hyacinth presence/absence, shoreline-associated Biomphalaria sudanica from PHS and RESP villages did not differ in relative abundance or prevalence of S. mansoni infection. Water hyacinth intrusions were associated with increased B. sudanica abundance. The deeper water snail Biomphalaria choanomphala was significantly more abundant in the PHS villages, and prevalence of S. mansoni among villages both before and after control was positively correlated with B. choanomphala abundance. Worm recoveries from sentinel mice did not differ between PHS and RESP villages, and abundance of non-schistosome trematode species was not associated with S. mansoni abundance. Biomphalaria choanomphala provides an alternative, deepwater mode of transmission that may favor greater persistence of S. mansoni in PHS villages. As we found evidence for ongoing S. mansoni transmission in all 10 villages, we conclude that conditions conducive for transmission and reinfection occur ubiquitously. This argues for an integrated, basin-wide plan for schistosomiasis control to counteract rapid reinfections facilitated by large snail populations and movements of infected people around the lake.
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Affiliation(s)
- Martin W Mutuku
- School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya.,Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Martina R Laidemitt
- Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico
| | - Brianna R Beechler
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon
| | - Ibrahim N Mwangi
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Fredrick O Otiato
- Influenza Surveillance Program, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Eric L Agola
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Horace Ochanda
- School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya
| | - Bishoy Kamel
- Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico
| | - Gerald M Mkoji
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Michelle L Steinauer
- Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon
| | - Eric S Loker
- Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico
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15
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Maier T, Wheeler NJ, Namigai EKO, Tycko J, Grewelle RE, Woldeamanuel Y, Klohe K, Perez-Saez J, Sokolow SH, De Leo GA, Yoshino TP, Zamanian M, Reinhard-Rupp J. Gene drives for schistosomiasis transmission control. PLoS Negl Trop Dis 2019; 13:e0007833. [PMID: 31856157 PMCID: PMC6922350 DOI: 10.1371/journal.pntd.0007833] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Schistosomiasis is one of the most important and widespread neglected tropical diseases (NTD), with over 200 million people infected in more than 70 countries; the disease has nearly 800 million people at risk in endemic areas. Although mass drug administration is a cost-effective approach to reduce occurrence, extent, and severity of the disease, it does not provide protection to subsequent reinfection. Interventions that target the parasites’ intermediate snail hosts are a crucial part of the integrated strategy required to move toward disease elimination. The recent revolution in gene drive technology naturally leads to questions about whether gene drives could be used to efficiently spread schistosome resistance traits in a population of snails and whether gene drives have the potential to contribute to reduced disease transmission in the long run. Responsible implementation of gene drives will require solutions to complex challenges spanning multiple disciplines, from biology to policy. This Review Article presents collected perspectives from practitioners of global health, genome engineering, epidemiology, and snail/schistosome biology and outlines strategies for responsible gene drive technology development, impact measurements of gene drives for schistosomiasis control, and gene drive governance. Success in this arena is a function of many factors, including gene-editing specificity and efficiency, the level of resistance conferred by the gene drive, how fast gene drives may spread in a metapopulation over a complex landscape, ecological sustainability, social equity, and, ultimately, the reduction of infection prevalence in humans. With combined efforts from across the broad global health community, gene drives for schistosomiasis control could fortify our defenses against this devastating disease in the future.
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Affiliation(s)
- Theresa Maier
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
| | - Nicolas James Wheeler
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Global Health Institute of Merck (KGaA), Eysins, Switzerland
| | | | - Josh Tycko
- Department of Genetics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Richard Ernest Grewelle
- Hopkins Marine Station, School of Humanities and Sciences, Stanford University, Pacific Grove, California, United States of America
| | - Yimtubezinash Woldeamanuel
- Department of Microbiology, Immunology & Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - Javier Perez-Saez
- Laboratory of Ecohydrology, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Susanne H. Sokolow
- Woods Institute for the Environment, Stanford University, Stanford, California, United States of America
- Marine Science Institute, University of California, Santa Barbara, California, United States of America
| | - Giulio A. De Leo
- Hopkins Marine Station, School of Humanities and Sciences, Stanford University, Pacific Grove, California, United States of America
| | - Timothy P. Yoshino
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mostafa Zamanian
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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16
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Shen J, Wang L, Peng M, Liu Z, Zhang B, Zhou T, Sun X, Wu Z. Recombinant Sj16 protein with novel activity alleviates hepatic granulomatous inflammation and fibrosis induced by Schistosoma japonicum associated with M2 macrophages in a mouse model. Parasit Vectors 2019; 12:457. [PMID: 31547847 PMCID: PMC6755699 DOI: 10.1186/s13071-019-3697-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 09/03/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Potent granulomatous inflammation responses induced by schistosome eggs and resultant fibrosis are the primary causes of morbidity in schistosomiasis. Recombinant Sj16 (rSj16), a 16-kDa protein of Schistosoma japonicum produced in Escherichia coli, has been demonstrated to have novel immunoregulatory effects in vivo and in vitro. Thus, this study investigated the anti-inflammatory and anti-fibrotic effects of rSj16 treatment in S. japonicum-infected mice and demonstrated the immune modulation between the schistosome and the host. METHODS Schistosoma japonicum infected mice were treated with the rSj16 protein and Sj16 peptide at different time points post-infection to assess their efficacy at the optimal time point. Sj16 peptide and/or Praziquantel (PZQ) treatments were initiated at week 5 post-infection to compare the therapeutic efficacy of each regimen. Hepatic granulomatous inflammation, fibrosis and cytokine production (pro-inflammatory, Th1, Th2, Th17 and regulatory cytokines IL-10) were detected. Moreover, M2 macrophages were measured to illuminate the mechanisms of Sj16. RESULTS The rSj16 protein and Sj16 peptide had significant protective effects in S. japonicum-infected mice, as shown by decreased granuloma formation, areas of collagen deposition and inhibition of pro-inflammatory Th1, Th2 and Th17 cytokine production. These protective activities were more obvious when animals were treated with either the Sj16 protein or peptide at early stages post-infection. Interestingly, the combined treatment of PZQ and Sj16 was more effective and upregulated IL-10 production than administration of PZQ alone in infected mice. Furthermore, the Sj16 treatment alleviated the pathological effects associated with activated M2 macrophages. CONCLUSIONS This study demonstrates the anti-inflammatory and anti-fibrotic effects of rSj16 in schistosomiasis. Therefore, the combination of rSj16 with PZQ could be a viable and promising therapeutic strategy for schistosomiasis. In addition, this investigation provides additional information on schistosome-mediated immune modulation and host-parasite interactions.
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Affiliation(s)
- Jia Shen
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Lifu Wang
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Mei Peng
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Zhen Liu
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Beibei Zhang
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Tao Zhou
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China.,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China
| | - Xi Sun
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China. .,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China. .,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China.
| | - Zhongdao Wu
- Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China. .,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, 510080, Guangdong, China. .,Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, Guangdong, China.
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17
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Turner HC, Walker M, Pion SDS, McFarland DA, Bundy DAP, Basáñez M. Economic evaluations of onchocerciasis interventions: a systematic review and research needs. Trop Med Int Health 2019; 24:788-816. [PMID: 31013395 PMCID: PMC6617745 DOI: 10.1111/tmi.13241] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To provide a systematic review of economic evaluations that has been conducted for onchocerciasis interventions, to summarise current key knowledge and to identify research gaps. METHOD A systematic review of the literature was conducted on the 8th of August 2018 using the PubMed (MEDLINE) and ISI Web of Science electronic databases. No date or language stipulations were applied to the searches. RESULTS We identified 14 primary studies reporting the results of economic evaluations of onchocerciasis interventions, seven of which were cost-effectiveness analyses. The studies identified used a variety of different approaches to estimate the costs of the investigated interventions/programmes. Originally, the studies only quantified the benefits associated with preventing blindness. Gradually, methods improved and also captured onchocerciasis-associated skin disease. Studies found that eliminating onchocerciasis would generate billions in economic benefits. The majority of the cost-effectiveness analyses evaluated annual mass drug administration (MDA). The estimated cost per disability-adjusted life year (DALY) averted of annual MDA varies between US$3 and US$30 (cost year variable). CONCLUSIONS The cost benefit and cost effectiveness of onchocerciasis interventions have consistently been found to be very favourable. This finding provides strong evidential support for the ongoing efforts to eliminate onchocerciasis from endemic areas. Although these results are very promising, there are several important research gaps that need to be addressed as we move towards the 2020 milestones and beyond.
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Affiliation(s)
- Hugo C. Turner
- Oxford University Clinical Research UnitWellcome Africa Asia ProgrammeHo Chi Minh CityVietnam
- Centre for Tropical Medicine and Global HealthNuffield Department of MedicineUniversity of OxfordOxfordUK
| | - Martin Walker
- London Centre for Neglected Tropical Disease ResearchDepartment of Pathobiology and Population SciencesRoyal Veterinary CollegeHatfieldUK
- London Centre for Neglected Tropical Disease ResearchDepartment of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK
| | - Sébastien D. S. Pion
- Institut de Recherche pour le DéveloppementUMI 233‐INSERMU1175‐Montpellier UniversityMontpellierFrance
| | | | | | - María‐Gloria Basáñez
- London Centre for Neglected Tropical Disease ResearchDepartment of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK
- MRC Centre for Global Infectious Disease AnalysisDepartment of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK
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18
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Nascimento GL, Domingues ALC, Ximenes RADA, Itria A, Cruz LN, Oliveira MRFD. Quality of life and quality-adjusted life years of chronic schistosomiasis mansoni patients in Brazil in 2015. Trans R Soc Trop Med Hyg 2019; 112:238-244. [PMID: 29945168 DOI: 10.1093/trstmh/try038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 04/12/2018] [Indexed: 02/06/2023] Open
Abstract
Background Measures of health-related quality of life (HRQoL) have been used to express the impact of neglected diseases and to generate indicators for health economic assessments. Schistosomiasis mansoni is a neglected disease with various clinical manifestations, including severe repercussions, caused by parasitic worms. Here we describe the quality of life of chronic schistosomiasis mansoni patients and estimate the quality-adjusted life years (QALYs) associated with chronic schistosomiasis mansoni in Brazil in 2015. Methods A HRQoL study was carried out using the three-level European Quality of Life 5-Dimensions (EQ-5D-3L) questionnaire in 147 chronic schistosomiasis mansoni patients at an outpatient monitoring facility of an endemic state for schistosomiasis. Results Losses in HRQoL were observed in all five dimensions of the EQ-5D-3L. Patients >60 y and 40-49 y of age reported the highest frequencies of problems. The average utility index was 0.71, and the median index was significantly lower among female patients and patients with comorbidities (0.68; p<0.05) compared with the entire sample. Approximately 26.7 QALYs were estimated for the study population and 31.2 QALYs for the chronic schistosomiasis mansoni patients in Brazil. Conclusions The advanced forms of schistosomiasis mansoni, even during treatment, contribute to important health losses in the population dealing with the disease.
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Affiliation(s)
- Gilmara Lima Nascimento
- Núcleo de Medicina Tropical - Universidade de Brasília. Campus Universitário Darcy Ribeiro, S/N. Asa Norte. Brasília-DF
| | - Ana Lúcia Coutinho Domingues
- Universidade Federal de Pernambuco, Programa de Pós-Graduação em Medicina Tropical. Av. Prof. Moraes Rego - s/n. 50670-901 - Cidade Universitária, Recife-PE
| | - Ricardo Arraes de Alencar Ximenes
- Universidade Federal de Pernambuco, Programa de Pós-Graduação em Medicina Tropical. Av. Prof. Moraes Rego - s/n. 50670-901 - Cidade Universitária, Recife-PE.,National Institute for Science and Technology for Health Technology Assessment (IATS/CNPq), Porto Alegre, Rio Grande do Sul, Brazil
| | - Alexander Itria
- National Institute for Science and Technology for Health Technology Assessment (IATS/CNPq), Porto Alegre, Rio Grande do Sul, Brazil.,Instituto de Patologia Tropical e Saúde Pública - Universidade Federal de Goiás. Rua 235 s/nº - Esq. com 1ª Avenida - Setor Universitário. Goiânia - GO
| | - Luciane Nascimento Cruz
- National Institute for Science and Technology for Health Technology Assessment (IATS/CNPq), Porto Alegre, Rio Grande do Sul, Brazil.,Hospital Moinhos de Vento, Rua Ramiro Barcelos, 630 sala 815. Porto Alegre - RS
| | - Maria Regina Fernandes de Oliveira
- Núcleo de Medicina Tropical - Universidade de Brasília. Campus Universitário Darcy Ribeiro, S/N. Asa Norte. Brasília-DF.,National Institute for Science and Technology for Health Technology Assessment (IATS/CNPq), Porto Alegre, Rio Grande do Sul, Brazil
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19
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Soloviova K, Fox EC, Dalton JP, Caffrey CR, Davies SJ. A secreted schistosome cathepsin B1 cysteine protease and acute schistosome infection induce a transient T helper 17 response. PLoS Negl Trop Dis 2019; 13:e0007070. [PMID: 30653492 PMCID: PMC6353221 DOI: 10.1371/journal.pntd.0007070] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 01/30/2019] [Accepted: 12/11/2018] [Indexed: 12/11/2022] Open
Abstract
The natural history of schistosome infection in the mammalian host is determined by CD4+ T helper responses mounted against different parasite life cycle stages. A T helper 2 (TH2) response to schistosome eggs is required for host survival and establishment of chronic infection. However, a TH2 cell-derived cytokine also contributes to an immune milieu that is conducive to schistosome growth and development. Thus, the same responses that allow for host survival have been co-opted by schistosomes to facilitate parasite development and transmission, underscoring the significance of CD4+ T cell responses to both worms and eggs in the natural history of schistosome infection. Here we show that a cathepsin B1 cysteine protease secreted by schistosome worms not only induces TH2 responses, but also TH1 and TH17 responses, by a mechanism that is dependent on the proteolytic activity of the enzyme. Further investigation revealed that, in addition to the expected TH1 and TH2 responses, acute schistosome infection also induces a transient TH17 response that is rapidly down-regulated at the onset of oviposition. TH17 responses are implicated in the development of severe egg-induced pathology. The regulation of worm-induced TH17 responses during acute infection could therefore influence the expression of high and low pathology states as infection progresses. Schistosomiasis, a neglected tropical disease caused by parasites of the genus Schistosoma, is prevalent throughout the developing world, with more than 230 million people infected. Left untreated, schistosome infection may cause relatively mild disease with some morbidity, or, in a minority of cases, result in severe pathology and death. These variable outcomes are recapitulated in animal models, where the natural history of schistosome infection is profoundly influenced by the responses of host CD4+ T helper cells. Type 2 CD4+ T cell (TH2) responses, which allow for host survival by limiting pathology, have ironically also been co-opted by schistosomes to promote parasite development. On the other hand, TH17 responses have been implicated in the development of severe pathology, in both experimentally infected animals and naturally infected humans. Here we show that a schistosome proteolytic enzyme (SmCB1), produced in the parasite gut and released into the bloodstream, induces both TH2 and TH17 responses by a mechanism that requires the enzyme’s inherent proteolytic activity. Further investigation revealed that acute schistosome infection also induces a transient TH17 response that is rapidly down-regulated once parasite egg-laying commences. Regulation of TH17 responses during early infection may help determine whether mild or severe pathology develops as the infection progresses.
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Affiliation(s)
- Kateryna Soloviova
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Ellen C. Fox
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - John P. Dalton
- School of Biological Sciences, Medical Biology Centre, Queen’s University Belfast, Northern Ireland, United Kingdom
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Stephen J. Davies
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
- * E-mail:
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20
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De Neve JW, Andriantavison RL, Croke K, Krisam J, Rajoela VH, Rakotoarivony RA, Rambeloson V, Schultz L, Qamruddin J, Verguet S. Health, financial, and education gains of investing in preventive chemotherapy for schistosomiasis, soil-transmitted helminthiases, and lymphatic filariasis in Madagascar: A modeling study. PLoS Negl Trop Dis 2018; 12:e0007002. [PMID: 30589847 PMCID: PMC6307713 DOI: 10.1371/journal.pntd.0007002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 11/15/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Neglected tropical diseases (NTDs) account for a large disease burden in sub-Saharan Africa. While the general cost-effectiveness of NTD interventions to improve health outcomes has been assessed, few studies have also accounted for the financial and education gains of investing in NTD control. METHODS We built on extended cost-effectiveness analysis (ECEA) methods to assess the health gains (e.g. infections, disability-adjusted life years or DALYs averted), household financial gains (out-of-pocket expenditures averted), and education gains (cases of school absenteeism averted) for five NTD interventions that the government of Madagascar aims to roll out nationally. The five NTDs considered were schistosomiasis, lymphatic filariasis, and three soil-transmitted helminthiases (Ascaris lumbricoides, Trichuris trichiura, and hookworm infections). RESULTS The estimated incremental cost-effectiveness for the roll-out of preventive chemotherapy for all NTDs jointly was USD125 per DALY averted (95% uncertainty range: 65-231), and its benefit-cost ratio could vary between 5 and 31. Our analysis estimated that, per dollar spent, schistosomiasis preventive chemotherapy, in particular, could avert a large number of infections (176,000 infections averted per $100,000 spent), DALYs (2,000 averted per $100,000 spent), and cases of school absenteeism (27,000 school years gained per $100,000 spent). CONCLUSION This analysis incorporates financial and education gains into the economic evaluation of health interventions, and therefore provides information about the efficiency of attainment of three Sustainable Development Goals (SDGs). Our findings reveal how the national scale-up of NTD control in Madagascar can help address health (SDG3), economic (SDG1), and education (SDG4) goals. This study further highlights the potentially large societal benefits of investing in NTD control in low-resource settings.
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Affiliation(s)
- Jan-Walter De Neve
- Institute of Global Health, Medical Faculty and University Hospital, Heidelberg University, Heidelberg, Germany
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston MA, United States of America
| | | | - Kevin Croke
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston MA, United States of America
- World Bank, Washington DC NW, Washington, DC, United States of America
| | - Johannes Krisam
- Institute of Medical Biometry and Informatics, Heidelberg University, Heidelberg, Germany
| | | | | | | | - Linda Schultz
- World Bank, Washington DC NW, Washington, DC, United States of America
| | - Jumana Qamruddin
- World Bank, Washington DC NW, Washington, DC, United States of America
| | - Stéphane Verguet
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston MA, United States of America
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21
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Potential Impact of Climate Change on Schistosomiasis: A Global Assessment Attempt. Trop Med Infect Dis 2018; 3:tropicalmed3040117. [PMID: 30400337 PMCID: PMC6306928 DOI: 10.3390/tropicalmed3040117] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 10/26/2018] [Accepted: 10/27/2018] [Indexed: 12/16/2022] Open
Abstract
Based on an ensemble of global circulation models (GCMs), four representative concentration pathways (RCPs) and several ongoing and planned Coupled Model Intercomparison Projects (CMIPs), the Intergovernmental Panel on Climate Change (IPCC) predicts that global, average temperatures will increase by at least 1.5 °C in the near future and more by the end of the century if greenhouse gases (GHGs) emissions are not genuinely tempered. While the RCPs are indicative of various amounts of GHGs in the atmosphere the CMIPs are designed to improve the workings of the GCMs. We chose RCP4.5 which represented a medium GHG emission increase and CMIP5, the most recently completed CMIP phase. Combining this meteorological model with a biological counterpart model accounted for replication and survival of the snail intermediate host as well as maturation of the parasite stage inside the snail at different ambient temperatures. The potential geographical distribution of the three main schistosome species: Schistosoma japonicum, S. mansoni and S. haematobium was investigated with reference to their different transmission capabilities at the monthly mean temperature, the maximum temperature of the warmest month(s) and the minimum temperature of the coldest month(s). The set of six maps representing the predicted situations in 2021⁻2050 and 2071⁻2100 for each species mainly showed increased transmission areas for all three species but they also left room for potential shrinkages in certain areas.
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22
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Schmidberger J, Weimer H, Schlingeloff P, Kratzer W, Grüner B. Health-related quality of life in patients with alveolar echinococcosis: a cross-sectional study. Infection 2018; 47:67-75. [PMID: 30225656 DOI: 10.1007/s15010-018-1219-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 09/11/2018] [Indexed: 01/30/2023]
Abstract
PURPOSE The Alveolar echinococcosis (AE) is a rare zoonosis caused by the parasite Echinococcus multilocularis. To date, nothing is known about the health-related quality of life (HRQoL) in patients with AE. The aim of the study was to evaluate the HRQoL in patients with AE in comparison of the healthy population. METHODS We used the 36-Item Short Form Health Survey (SF-36) questionnaire to evaluate the HRQoL. The SF-36 scales have a range of 0-100 (0 represents the worst and 100 the most favourable state of health). SAS Version 9.2 was used for the statistical analysis of AE-cases (n = 30) and the healthy control group (n = 35). RESULTS The analysis showed that the HRQoL in people with AE is reduced in comparison with the control population. The study group consisted of 15 (50.0%) men and 15 (50.0%) women; the control group of 16 (45.7%) men and 19 (54.3%) women. The mean age was 55.73 ± 16.65 years, while that of the control group was 54.57 ± 15.34 years. The physical quality of life in patients with AE (45.21 ± 11.42) was not significantly less than that of the control group (50.54 ± 10.52); p = 0.0568. Nevertheless, AE-patients show lower SF-36 scores for the physical quality of life. For the mental quality of life, patients with AE had a significantly lower score (45.46 ± 10.57) than the control group (51.57 ± 9.04); p = 0.0154. CONCLUSIONS The HRQoL in people with AE is reduced in comparison with a control population. Assessment of the physical and mental quality of life in patients with AE may help to evaluate the patient outcome.
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Affiliation(s)
- Julian Schmidberger
- Department of Internal Medicine I, Ulm University Hospital, Albert-Einstein-Allee 23, 89081, Ulm, Germany.
| | - Henriette Weimer
- Department of Internal Medicine I, Ulm University Hospital, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Patrycja Schlingeloff
- Department of Internal Medicine I, Ulm University Hospital, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Wolfgang Kratzer
- Department of Internal Medicine I, Ulm University Hospital, Albert-Einstein-Allee 23, 89081, Ulm, Germany
| | - Beate Grüner
- Department of Internal Medicine III, Ulm University Hospital, Albert-Einstein-Allee 23, 89081, Ulm, Germany
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23
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Schulz JD, Moser W, Hürlimann E, Keiser J. Preventive Chemotherapy in the Fight against Soil-Transmitted Helminthiasis: Achievements and Limitations. Trends Parasitol 2018; 34:590-602. [DOI: 10.1016/j.pt.2018.04.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 04/26/2018] [Accepted: 04/27/2018] [Indexed: 02/06/2023]
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24
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Binns C, Low WY. Controlling Worms Needs Traditional Public Health Programs. Asia Pac J Public Health 2018; 30:204-206. [DOI: 10.1177/1010539518769722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Colin Binns
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Wah Yun Low
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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25
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Ding X, Njus Z, Kong T, Su W, Ho CM, Pandey S. Effective drug combination for Caenorhabditis elegans nematodes discovered by output-driven feedback system control technique. SCIENCE ADVANCES 2017; 3:eaao1254. [PMID: 28983514 PMCID: PMC5627981 DOI: 10.1126/sciadv.aao1254] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/13/2017] [Indexed: 02/05/2023]
Abstract
Infections from parasitic nematodes (or roundworms) contribute to a significant disease burden and productivity losses for humans and livestock. The limited number of anthelmintics (or antinematode drugs) available today to treat these infections are rapidly losing their efficacy as multidrug resistance in parasites becomes a global health challenge. We propose an engineering approach to discover an anthelmintic drug combination that is more potent at killing wild-type Caenorhabditis elegans worms than four individual drugs. In the experiment, freely swimming single worms are enclosed in microfluidic drug environments to assess the centroid velocity and track curvature of worm movements. After analyzing the behavioral data in every iteration, the feedback system control (FSC) scheme is used to predict new drug combinations to test. Through a differential evolutionary search, the winning drug combination is reached that produces minimal centroid velocity and high track curvature, while requiring each drug in less than their EC50 concentrations. The FSC approach is model-less and does not need any information on the drug pharmacology, signaling pathways, or animal biology. Toward combating multidrug resistance, the method presented here is applicable to the discovery of new potent combinations of available anthelmintics on C. elegans, parasitic nematodes, and other small model organisms.
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Affiliation(s)
- Xianting Ding
- State Key Laboratory of Oncogenes and Related Genes, Institute for Personalized Medicine, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Zach Njus
- Department of Electrical and Computer Engineering, Iowa State University, Ames, IA 50011, USA
| | - Taejoon Kong
- Department of Electrical and Computer Engineering, Iowa State University, Ames, IA 50011, USA
| | - Wenqiong Su
- State Key Laboratory of Oncogenes and Related Genes, Institute for Personalized Medicine, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Chih-Ming Ho
- Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Santosh Pandey
- Department of Electrical and Computer Engineering, Iowa State University, Ames, IA 50011, USA
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Bustinduy AL, Stothard JR, Friedman JF. Paediatric and maternal schistosomiasis: shifting the paradigms. Br Med Bull 2017; 123:115-125. [PMID: 28910994 PMCID: PMC6279106 DOI: 10.1093/bmb/ldx028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 07/16/2017] [Indexed: 11/13/2022]
Abstract
BACKGROUND In endemic areas, schistosomiasis causes both overt and subclinical disease in young children and their mothers, as well as in returned travellers. SOURCES OF DATA Key recently published literature. AREAS OF AGREEMENT An action plan for paediatric schistosomiasis and female genital schistosomiasis (FGS) is needed with expanded access to praziquantel (PZQ) treatment required. AREAS OF CONTROVERSY Schistosomiasis-related morbidity is underappreciated. Present and future demand for PZQ treatment is bottlenecked, imbalanced and inequitable. Current dosing, treatment algorithms and access plans are suboptimal with treatment stalled during pregnancy. GROWING POINTS Raised dosing of PZQ (>40 mg/kg) is being explored in young children. Surveillance of female genital schistosomiasis FGS is increasing. Use of PZQ in pregnancy is safe and preventive chemotherapy guidelines are being revised in morbidity- and transmission-control settings. AREAS TIMELY FOR DEVELOPING RESEARCH Shifting focus of population-level control to individual-case management. Detection and prevention of FGS within general health services and integration of PZQ treatment for women and children in antenatal clinics. Feasibility studies assessing alternative and expanded access to PZQ treatment to at-risk children and mothers and pregnant women.
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Affiliation(s)
- Amaya L Bustinduy
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - J Russell Stothard
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Jennifer F Friedman
- Center for International Health Research, Rhode Island Hospital, 55 Claverick Street, Suite 101, Providence, RI 02903, USA
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27
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Purinergic signaling in schistosomal infection. Biomed J 2016; 39:316-325. [PMID: 27884378 PMCID: PMC6138794 DOI: 10.1016/j.bj.2016.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 06/27/2016] [Accepted: 06/30/2016] [Indexed: 01/06/2023] Open
Abstract
Human schistosomiasis is a chronic inflammatory disease caused by blood fluke worms belonging to the genus Schistosoma. Health metrics indicate that the disease is related to an elevated number of years lost-to-disability and years lost-to-life. Schistosomiasis is an intravascular disease that is related to a Th1 and Th2 immune response polarization, and the degree of polarization affects the outcome of the disease. The purinergic system is composed of adenosine and nucleotides acting as key messenger molecules. Moreover, nucleotide-transforming enzymes and cell-surface purinergic receptors are obligatory partners of this purinergic signaling. In mammalian cells, purinergic signaling modulates innate immune responses and inflammation among other functions; conversely purinergic signaling may also be modulated by inflammatory mediators. Moreover, schistosomes also express some enzymes of the purinergic system, and it is possible that worms modulate host purinergic signaling. Current data obtained in murine models of schistosomiasis support the notion that the host purinergic system is altered by the disease. The dysfunction of adenosine receptors, metabotropic P2Y and ionotropic P2X7 receptors, and NTPDases likely contributes to disease morbidity.
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28
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Vukman KV, Lalor R, Aldridge A, O'Neill SM. Mast cells: new therapeutic target in helminth immune modulation. Parasite Immunol 2016; 38:45-52. [PMID: 26577605 DOI: 10.1111/pim.12295] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 11/02/2015] [Indexed: 02/06/2023]
Abstract
Helminth infection and their secreted antigens have a protective role in many immune-mediated inflammatory disorders such as inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis. However, studies have focused primarily on identifying immune protective mechanisms of helminth infection and their secreted molecules on dendritic cells and macrophages. Given that mast cells have been shown to be implicated in the pathogenesis and progression of many inflammatory disorders, their role should also be examined and considered as cellular target for helminth-based therapies. As there is a dearth of studies examining the interaction of helminth-derived antigens and mast cells, this review will focus on the role of mast cells during helminth infection and examine our current understanding of the involvement of mast cells in TH 1/TH 17-mediated immune disorders. In this context, potential mechanisms by which helminths could target the TH 1/TH 17 promoting properties of mast cells can be identified to unveil novel therapeutic mast cell driven targets in combating these inflammatory disorders.
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Affiliation(s)
- K V Vukman
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Nagyvarad ter 4., H-1089, Budapest, Hungry.,Parasite Immune Modulation Group, School of Biotechnology, Faculty of Science and Health, Dublin City University, Glasnevin, Dublin, Ireland
| | - R Lalor
- Parasite Immune Modulation Group, School of Biotechnology, Faculty of Science and Health, Dublin City University, Glasnevin, Dublin, Ireland
| | - A Aldridge
- Parasite Immune Modulation Group, School of Biotechnology, Faculty of Science and Health, Dublin City University, Glasnevin, Dublin, Ireland
| | - S M O'Neill
- Parasite Immune Modulation Group, School of Biotechnology, Faculty of Science and Health, Dublin City University, Glasnevin, Dublin, Ireland
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29
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Ezeamama AE, He CL, Shen Y, Yin XP, Binder SC, Campbell CH, Rathbun S, Whalen CC, N'Goran EK, Utzinger J, Olsen A, Magnussen P, Kinung'hi S, Fenwick A, Phillips A, Ferro J, Karanja DMS, Mwinzi PNM, Montgomery S, Secor WE, Hamidou A, Garba A, King CH, Colley DG. Gaining and sustaining schistosomiasis control: study protocol and baseline data prior to different treatment strategies in five African countries. BMC Infect Dis 2016; 16:229. [PMID: 27230666 PMCID: PMC4880878 DOI: 10.1186/s12879-016-1575-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 05/17/2016] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study. METHODS Beginning in 2009, SCORE held a series of meetings to specify empirical questions and design studies related to different schedules of PCT for schistosomiasis control in communities with high (gaining control studies) and moderate (sustaining control studies) prevalence of Schistosoma infection among school-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention strategies. RESULTS These studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control. CONCLUSIONS We expect that the study outcomes will provide data for decision-making for country programme managers and a rich resource of information to the schistosomiasis research community. TRIAL REGISTRATION The trials are registered at International Standard Randomised Controlled Trial registry (identifiers: ISRCTN99401114 , ISRCTN14849830 , ISRCTN16755535 , ISRCTN14117624 , ISRCTN95819193 and ISRCTN32045736 ).
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Affiliation(s)
- Amara E Ezeamama
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA.
| | - Chun-La He
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA
| | - Ye Shen
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA
| | - Xiao-Ping Yin
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA
| | - Sue C Binder
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Carl H Campbell
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Stephen Rathbun
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA
| | - Christopher C Whalen
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, GA, USA
| | - 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
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | | | | | - Alan Fenwick
- Schistosomiasis Control Initiative, Imperial College, London, UK
| | - Anna Phillips
- Schistosomiasis Control Initiative, Imperial College, London, UK
| | - Josefo Ferro
- Catholic University of Mozambique, Beira, Mozambique
| | - Diana M S Karanja
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Pauline N M Mwinzi
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | | | - W Evan Secor
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Amina Hamidou
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), Niamey, Niger
| | - Amadou Garba
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), Niamey, Niger
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Daniel G Colley
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA.,Department of Microbiology, University of Georgia, Athens, GA, USA
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30
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Turner HC, Bettis AA, Chu BK, McFarland DA, Hooper PJ, Ottesen EA, Bradley MH. The health and economic benefits of the global programme to eliminate lymphatic filariasis (2000-2014). Infect Dis Poverty 2016; 5:54. [PMID: 27388873 PMCID: PMC4937583 DOI: 10.1186/s40249-016-0147-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 05/18/2016] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Lymphatic filariasis (LF), also known as elephantiasis, is a neglected tropical disease (NTD) targeted for elimination through a Global Programme to Eliminate LF (GPELF). Between 2000 and 2014, the GPELF has delivered 5.6 billion treatments to over 763 million people. Updating the estimated health and economic benefits of this significant achievement is important in justifying the resources and investment needed for eliminating LF. METHOD We combined previously established models to estimate the number of clinical manifestations and disability-adjusted life years (DALYs) averted from three benefit cohorts (those protected from acquiring infection, those with subclinical morbidity prevented from progressing and those with clinical disease alleviated). The economic savings associated with this disease prevention was then analysed in the context of prevented medical expenses incurred by LF clinical patients, potential income loss through lost-labour, and prevented costs to the health system to care for affected individuals. The indirect cost estimates were calculated using the human capital approach. A combination of four wage sources was used to estimate the fair market value of time for an agricultural worker with LF infection (to ensure a conservative estimate, the lowest wage value was used). RESULTS We projected that due to the first 15 years of the GPELF 36 million clinical cases and 175 (116-250) million DALYs will potentially be averted. It was estimated that due to this notable health impact, US$100.5 billion will potentially be saved over the lifetimes of the benefit cohorts. This total amount results from summing the medical expenses incurred by LF patients (US$3 billion), potential income loss (US$94 billion), and costs to the health system (US$3.5 billion) that were projected to be prevented. The results were subjected to sensitivity analysis and were most sensitive to the assumed percentage of work hours lost for those suffering from chronic disease (changing the total economic benefit between US$69.30-150.7 billion). CONCLUSIONS Despite the limitations of any such analysis, this study identifies substantial health and economic benefits that have resulted from the first 15 years of the GPELF, and it highlights the value and importance of continued investment in the GPELF.
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Affiliation(s)
- Hugo C Turner
- London Centre for Neglected Tropical Disease Research, London, UK.
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - Alison A Bettis
- London Centre for Neglected Tropical Disease Research, London, UK
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK
| | - Brian K Chu
- Neglected Tropical Diseases Support Center, Task Force for Global Health, Decatur, GA, USA
| | | | - Pamela J Hooper
- Neglected Tropical Diseases Support Center, Task Force for Global Health, Decatur, GA, USA
| | - Eric A Ottesen
- Neglected Tropical Diseases Support Center, Task Force for Global Health, Decatur, GA, USA
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Xu J, Bergquist R, Qian YJ, Wang Q, Yu Q, Peeling R, Croft S, Guo JG, Zhou XN. China-Africa and China-Asia Collaboration on Schistosomiasis Control: A SWOT Analysis. ADVANCES IN PARASITOLOGY 2016; 92:435-66. [PMID: 27137455 DOI: 10.1016/bs.apar.2016.02.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Schistosomiasis, a disease caused by a trematode, parasitic worm, is a worldwide public health problem. In spite of great progress with regard to morbidity control, even elimination of this infection in recent decades, there are still challenges to overcome in sub-Saharan Africa and endemic areas in Southeast Asia. Regarded as one of the most successful countries with respect to schistosomiasis control, The People's Republic of China has accumulated considerable experience and learnt important lessons in various local settings that could benefit schistosomiasis control in other endemic countries. Based on an analysis of conceived strengths, weaknesses, opportunities and threats (SWOT) of potential collaborative activities with regard to schistosomiasis in Africa and Asia, this article addresses the importance of collaborative efforts and explores the priorities that would be expected to facilitate the transfer of Chinese experience to low- and middle-income countries in Africa and Asia.
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Affiliation(s)
- J Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, The People's Republic of China; Key Laboratory of Parasite & Vector Biology, Ministry of Public Health, Shanghai, The People's Republic of China; WHO Collaborating Center for Tropical Diseases, Shanghai, The People's Republic of China
| | - R Bergquist
- Geospatial Health, University of Naples Federico II, Naples, Italy
| | - Y-J Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, The People's Republic of China; Key Laboratory of Parasite & Vector Biology, Ministry of Public Health, Shanghai, The People's Republic of China; WHO Collaborating Center for Tropical Diseases, Shanghai, The People's Republic of China
| | - Q Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, The People's Republic of China; Key Laboratory of Parasite & Vector Biology, Ministry of Public Health, Shanghai, The People's Republic of China; WHO Collaborating Center for Tropical Diseases, Shanghai, The People's Republic of China
| | - Q Yu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, The People's Republic of China; Key Laboratory of Parasite & Vector Biology, Ministry of Public Health, Shanghai, The People's Republic of China; WHO Collaborating Center for Tropical Diseases, Shanghai, The People's Republic of China
| | - R Peeling
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - S Croft
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - J-G Guo
- World Health Organization, Geneva, Switzerland
| | - X-N Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, The People's Republic of China; Key Laboratory of Parasite & Vector Biology, Ministry of Public Health, Shanghai, The People's Republic of China; WHO Collaborating Center for Tropical Diseases, Shanghai, The People's Republic of China
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Ziniel PD, Karumudi B, Barnard AH, Fisher EMS, Thatcher GRJ, Podust LM, Williams DL. The Schistosoma mansoni Cytochrome P450 (CYP3050A1) Is Essential for Worm Survival and Egg Development. PLoS Negl Trop Dis 2015; 9:e0004279. [PMID: 26713732 PMCID: PMC4694641 DOI: 10.1371/journal.pntd.0004279] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 11/13/2015] [Indexed: 12/29/2022] Open
Abstract
Schistosomiasis affects millions of people in developing countries and is responsible for more than 200,000 deaths annually. Because of toxicity and limited spectrum of activity of alternatives, there is effectively only one drug, praziquantel, available for its treatment. Recent data suggest that drug resistance could soon be a problem. There is therefore the need to identify new drug targets and develop drugs for the treatment of schistosomiasis. Analysis of the Schistosoma mansoni genome sequence for proteins involved in detoxification processes found that it encodes a single cytochrome P450 (CYP450) gene. Here we report that the 1452 bp open reading frame has a characteristic heme-binding region in its catalytic domain with a conserved heme ligating cysteine, a hydrophobic leader sequence present as the membrane interacting region, and overall structural conservation. The highest sequence identity to human CYP450s is 22%. Double stranded RNA (dsRNA) silencing of S. mansoni (Sm)CYP450 in schistosomula results in worm death. Treating larval or adult worms with antifungal azole CYP450 inhibitors results in worm death at low micromolar concentrations. In addition, combinations of SmCYP450-specific dsRNA and miconazole show additive schistosomicidal effects supporting the hypothesis that SmCYP450 is the target of miconazole. Treatment of developing S. mansoni eggs with miconazole results in a dose dependent arrest in embryonic development. Our results indicate that SmCYP450 is essential for worm survival and egg development and validates it as a novel drug target. Preliminary structure-activity relationship suggests that the 1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethan-1-ol moiety of miconazole is necessary for activity and that miconazole activity and selectivity could be improved by rational drug design. Over 600 million people in endemic countries are at risk of contracting schistosomiasis, which results in over 200,000 deaths each year and significant illness to most people that are infected. There are concerns that the drug widely used for the treatment of schistosomiasis, praziquantel, may be losing efficacy due to evolution of drug resistant worms. Since the disease mainly affects the poor in developing countries, pharmaceutical companies have little interest in developing new drugs and none are currently being tested. In this paper we focus on a novel parasite protein, cytochrome P450, which we propose to be a new drug target. Worms are unusual in having only one cytochrome P450 gene; humans have 57 cytochrome P450 genes. By using reverse genetic and chemical approaches we found that the schistosome cytochrome P450 is essential for worm survival and egg development and, therefore, is an essential and druggable target. Drugs that target fungal cytochrome P450s and are already in use for treating several human diseases were identified as potential hits for further development for schistosomiasis treatment.
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Affiliation(s)
- Peter D. Ziniel
- Department of Immunology & Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Bhargava Karumudi
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Andrew H. Barnard
- Department of Immunology & Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Ethan M. S. Fisher
- Department of Immunology & Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Gregory R. J. Thatcher
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Larissa M. Podust
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - David L. Williams
- Department of Immunology & Microbiology, Rush University Medical Center, Chicago, Illinois, United States of America
- * E-mail:
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Turner HC, Truscott JE, Hollingsworth TD, Bettis AA, Brooker SJ, Anderson RM. Cost and cost-effectiveness of soil-transmitted helminth treatment programmes: systematic review and research needs. Parasit Vectors 2015; 8:355. [PMID: 26137945 PMCID: PMC4499443 DOI: 10.1186/s13071-015-0885-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 05/05/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In this time of rapidly expanding mass drug administration (MDA) coverage and the new commitments for soil-transmitted helminth (STH) control, it is essential that resources are allocated in an efficient manner to have the greatest impact. However, many questions remain regarding how best to deliver STH treatment programmes; these include which age-groups should be targeted and how often. To perform further analyses to investigate what the most cost-effective control strategies are in different settings, accurate cost data for targeting different age groups at different treatment frequencies (in a range of settings) are essential. METHODS Using the electronic databases PubMed, MEDLINE, and ISI Web of Knowledge, we perform a systematic review of costing studies and cost-effectiveness evaluations for potential STH treatment strategies. We use this review to highlight research gaps and outline the key future research needs. RESULTS We identified 29 studies reporting costs of STH treatment and 17 studies that investigated its cost-effectiveness. The majority of these pertained to programmes only targeting school-aged children (SAC), with relatively few studies investigating alternative preventive chemotherapy (PCT) treatment strategies. The methods of cost data collection, analysis and reporting were highly variable among the different studies. Only four of the costing studies were found to have high applicability for use in forthcoming economic evaluations. There are also very few studies quantifying the costs of increasing the treatment frequency. CONCLUSIONS The absence of cost data and inconsistencies in the collection and analysis methods constitutes a major research gap for STH control. Detailed and accurate costs of targeting different age groups or increasing treatment frequency will be essential to formulate cost-effective public health policy. Defining the most cost-effective control strategies in different settings is of high significance during this period of expanding MDA coverage and new resource commitments for STH control.
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Affiliation(s)
- Hugo C Turner
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - James E Truscott
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - T Déirdre Hollingsworth
- Mathematics Institute, University of Warwick, Coventry, CV4 7AL, UK. .,School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
| | - Alison A Bettis
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - Simon J Brooker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK. .,Kenya Medical Research Institute, Nairobi, Kenya.
| | - Roy M Anderson
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
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Smit CH, van Diepen A, Nguyen DL, Wuhrer M, Hoffmann KF, Deelder AM, Hokke CH. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs. Mol Cell Proteomics 2015; 14:1750-69. [PMID: 25883177 PMCID: PMC4587318 DOI: 10.1074/mcp.m115.048280] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Indexed: 11/30/2022] Open
Abstract
Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles of glycans and antigenic glycan-motifs during a range of critical stages of the complex schistosome lifecycle. We performed a longitudinal profiling study covering schistosome glycosylation throughout worm- and egg-development using a mass spectrometry-based glycomics approach. Our study revealed that during worm development N-glycans with Galβ1–4(Fucα1–3)GlcNAc (LeX) and core-xylose motifs were rapidly lost after cercariae to schistosomula transformation, whereas GalNAcβ1–4GlcNAc (LDN)-motifs gradually became abundant and predominated in adult worms. LeX-motifs were present on glycolipids up to 2 weeks of schistosomula development, whereas glycolipids with mono- and multifucosylated LDN-motifs remained present up to the adult worm stage. In contrast, expression of complex O-glycans diminished to undetectable levels within days after transformation. During egg development, a rich diversity of N-glycans with fucosylated motifs was expressed, but with α3-core fucose and a high degree of multifucosylated antennae only in mature eggs and miracidia. N-glycan antennae were exclusively LDN-based in miracidia. O-glycans in the mature eggs were also diverse and contained LeX- and multifucosylated LDN, but none of these were associated with miracidia in which we detected only the Galβ1–3(Galβ1–6)GalNAc core glycan. Immature eggs also exhibited short O-glycan core structures only, suggesting that complex fucosylated O-glycans of schistosome eggs are derived primarily from glycoproteins produced by the subshell envelope in the developed egg. Lipid glycans with multifucosylated GlcNAc repeats were present throughout egg development, but with the longer highly fucosylated stretches enriched in mature eggs and miracidia. This global analysis of the developing schistosome's glycome provides new insights into how stage-specifically expressed glycans may contribute to different aspects of schistosome-host interactions.
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Affiliation(s)
- Cornelis H Smit
- From the ‡Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Angela van Diepen
- From the ‡Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - D Linh Nguyen
- From the ‡Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Manfred Wuhrer
- §Center for Proteomics and Metabolomics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Karl F Hoffmann
- ¶Institute of Biological Environmental and Rural Sciences (IBERS), Aberystwyth University, Penglais Campus, Aberystwyth SY23 3FG, United Kingdom
| | - André M Deelder
- §Center for Proteomics and Metabolomics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Cornelis H Hokke
- From the ‡Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands;
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Becker SL, Fürst T, Addiss DG, Utzinger J. Assessing numbers and faces: a prerequisite for improving access to lymphatic filariasis morbidity care. Trans R Soc Trop Med Hyg 2015; 109:357-9. [PMID: 25778735 DOI: 10.1093/trstmh/trv022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/23/2015] [Indexed: 11/12/2022] Open
Abstract
Concerted efforts to eliminate lymphatic filariasis worldwide have registered success; multiple rounds of mass drug administration have led to the interruption of transmission in many previously endemic areas. However, the management of patients with established clinical disease (e.g., lymphoedema, hydrocoele and acute dermatolymphangioadenitis) has not been addressed sufficiently. Two recent studies from Malawi underscore the need for accurate epidemiological and clinical data, and comprehensive morbidity assessments across various domains of daily life. Addressing these issues will guide the implementation of programmes to improve access to treatment and disability prevention for affected individuals in Malawi and beyond.
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Affiliation(s)
- Sören L Becker
- 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 Institute of Medical Microbiology and Hygiene, Saarland University Medical Center, Kirrberger Straße, Building 43, D-66421 Homburg/Saar, Germany
| | - Thomas Fürst
- Centre for Health Policy and Department of Infectious Disease Epidemiology, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - David G Addiss
- Children Without Worms, Task Force for Global Health, 325 Swanton Way, Decatur, GA 30030, USA
| | - 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
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Spatio-temporal transmission and environmental determinants of Schistosomiasis Japonica in Anhui Province, China. PLoS Negl Trop Dis 2015; 9:e0003470. [PMID: 25659112 PMCID: PMC4319937 DOI: 10.1371/journal.pntd.0003470] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 12/11/2014] [Indexed: 11/16/2022] Open
Abstract
Background Schistosomiasis japonica still remains of public health and economic significance in China, especially in the lake and marshland areas along the Yangtze River Basin, where the control of transmission has proven difficult. In the study, we investigated spatio-temporal variations of S. japonicum infection risk in Anhui Province and assessed the associations of the disease with key environmental factors with the aim of understanding the mechanism of the disease and seeking clues to effective and sustainable schistosomiasis control. Methodology/Principal Findings Infection data of schistosomiasis from annual conventional surveys were obtained at the village level in Anhui Province, China, from 2000 to 2010 and used in combination with environmental data. The spatio-temporal kriging model was used to assess how these environmental factors affected the spatio-temporal pattern of schistosomiasis risk. Our results suggested that seasonal variation of the normalized difference vegetation index (NDVI), seasonal variation of land surface temperature at daytime (LSTD), and distance to the Yangtze River were negatively significantly associated with risk of schistosomiasis. Predictive maps showed that schistosomiasis prevalence remained at a low level and schistosomiasis risk mainly evolved along the Yangtze River. Schistosomiasis risk also followed a focal spatial pattern, fluctuating temporally with a peak (the largest spatial extent) in 2005 and then contracting gradually but with a scattered distribution until 2010. Conclusion The fitted spatio-temporal kriging model can capture variations of schistosomiasis risk over space and time. Combined with techniques of geographic information system (GIS) and remote sensing (RS), this approach facilitates and enriches risk modeling of schistosomiasis, which in turn helps to identify prior areas for effective and sustainable control of schistosomiasis in Anhui Province and perhaps elsewhere in China. Schistosomiasis japonica is one of the most serious parasitic diseases in China. It is estimated that more than 50 million people are still at risk, especially those living in the lake and marshland areas along the Yangtze River Basin. The Chinese government has made great efforts to implement schistosomiasis control programs since 1950s. The latest, major two programs are the 10-year World Bank Loan Project (WBLP) terminated in 2001, which was based on large-scale chemotherapy, and the national integrated control strategy implemented since 2005, which was aimed at reducing the roles of bovines and humans as infection sources. Based on spatio-temporal analyses of the S. japonicum infection prevalence data during 2000–2010 in Anhui Province, we found schistosomiasis prevalence remained at a low level but the spatial distribution of the disease became widely scattered at the later stage of the study period, suggesting that the integrated program could not fully effectively reduce the spatial extent of schistosomiasis risk. To achieve an effective and sustainable control strategy, we emphasize the need to control snail habitats within areas of high schistosomiasis risk.
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Affiliation(s)
- Charles H. King
- Center for Global Health and Diseases, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
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Utzinger J, Brattig NW, Leonardo L, Zhou XN, Bergquist R. Progress in research, control and elimination of helminth infections in Asia. Acta Trop 2015; 141:135-45. [PMID: 25446170 DOI: 10.1016/j.actatropica.2014.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Global health has substantially improved over the past 20 years. In low- and middle-income countries, in particular, great strives have been made in the control of communicable diseases, including helminth infections. Nevertheless, the most marginalised communities still suffer from infectious diseases that are intimately connected with poverty and lack of access to essential commodities and services, such as clean water, improved sanitation and sufficient food. A two-pronged approach is thus necessary: (i) intensifying control in remaining high-endemicity areas and pockets of high transmission; and (ii) moving from morbidity control to interruption of disease transmission in low-endemicity areas with the goal of local elimination. The latter will require new tools and strategies, going hand-in-hand with strong partnerships and new strategic alliances. In this special issue of Acta Tropica, 35 articles are featured that, together, provide an up-to-date overview of the latest progress made in research, control and elimination of helminth infections in East and Southeast Asia. The first 12 articles expound tools and approaches for improved detection, surveillance and monitoring of helminth infections. Control and elimination approaches for the most important helminth infections are revisited in the next 20 articles. The three remaining articles are cross-cutting pieces examining the interface of agriculture, environment and helminth infections and providing a rationale for integrated, multi-sectorial control approaches that are necessary for sustaining helminthiasis control and progressively moving towards elimination. An interesting aspect revealed through an in-depth analysis of the provenance of the 35 contributions is that the People's Republic of China emerges as a key player in global health, which is documented through its prominent role in research and control of helminth infection and networking throughout Asia. Policy implications are discussed and will hopefully shape the future agenda for the control and elimination of helminth infections the world over.
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Affiliation(s)
- 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.
| | - Norbert W Brattig
- Tropical Medicine Section, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Str. 74, D-20359 Hamburg, Germany
| | - Lydia Leonardo
- College of Public Health, University of the Philippines-Manila, Manila, Philippines
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, People's Republic of China; Key Laboratory on Biology of Parasite and Vector, Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai 200025, People's Republic of China
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Hürlimann E, Houngbedji CA, Yapi RB, Ndri PB, Silué KD, Soro G, Kouamé FN, Fürst T, Utzinger J, N'Goran EK, Raso G. Health-related quality of life among school children with parasitic infections: findings from a national cross-sectional survey in Côte d'Ivoire. PLoS Negl Trop Dis 2014; 8:e3287. [PMID: 25474579 PMCID: PMC4256278 DOI: 10.1371/journal.pntd.0003287] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 09/22/2014] [Indexed: 12/28/2022] Open
Abstract
Background Parasitic infections are still of considerable public health relevance, notably among children in low- and middle-income countries. Measures to assess the magnitude of ill-health in infected individuals, however, are debated and patient-based proxies through generic health-related quality of life (HrQoL) instruments are among the proposed strategies. Disability estimates based on HrQoL are still scarce and conflicting, and hence, there is a need to strengthen the current evidence-base. Methodology Between November 2011 and February 2012, a national school-based cross-sectional survey was conducted in Côte d'Ivoire. Children underwent parasitological and clinical examination to assess infection status with Plasmodium and helminth species and clinical parameters, and responded to a questionnaire interview incorporating sociodemographic characteristics, self-reported morbidity, and HrQoL. Validity analysis of the HrQoL instrument was performed, assessing floor and ceiling effects, internal consistency, and correlation with morbidity scores. Multivariate regression models were applied to identify significant associations between HrQoL and children's parasitic infection and clinical status. Principal Findings Parasitological examination of 4,848 children aged 5–16 years revealed Plasmodium spp., hookworm, Schistosoma haematobium, Schistosoma mansoni, Ascaris lumbricoides, and Trichuris trichiura prevalences of 75.0%, 17.2%, 5.7%, 3.7%, 1.8%, and 1.3%, respectively. Anemic children showed a significant 1-point reduction in self-rated HrQoL on a scale from 0 to 100, whereas no significant negative association between HrQoL and parasite infection was observed. The 12-item HrQoL questionnaire proofed useful, as floor and ceiling effects were negligible, internally consistent (Cronbach's alpha = 0.71), and valid, as revealed by significant negative correlations and associations with children's self-reported and clinically assessed morbidity. Conclusions/Significance Our results suggest that HrQoL tools are not sufficiently sensitive to assess subtle morbidities due to parasitic infection in Ivorian school-aged children. However, more advanced morbid sequelae (e.g., anemia), were measurable by the instrument's health construct. Further investigations on health impacts of parasitic infection among school-aged children and refinement of generic HrQoL questionnaires are warranted. Infectious diseases like malaria and parasitic worms affect hundreds of millions of people, and impact physical and cognitive development of children in Africa, Asia, and the Americas. Over the past 20 years, it was debated how the magnitude of ill-health due to these conditions should be assessed. One proposed strategy was to include patient-based ratings of wellbeing by administration of health-related quality of life (HrQoL) questionnaires. In order to provide new evidence on disability from parasitic infections, we conducted HrQoL interviews with children aged 5–16 years from 92 schools across Côte d'Ivoire. Children were examined for parasitic infections and clinical signs like anemia, malnutrition, and organ enlargement. We compared the self-rated HrQoL of infected and non-infected children and also considered their sociodemographic background. We could not identify lowered HrQoL in infected children, but we found that children with anemia reported a 1-point lower score on a 100-point HrQoL scale in comparison with their non-anemic counterparts. We consider our HrQoL questionnaire as useful and valid, but would recommend its further testing and development in few purposefully selected settings. Further investigation of disability induced by malaria and parasitic worm infections is warranted.
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Affiliation(s)
- 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
| | - Clarisse A. Houngbedji
- 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
- Unité de Formation et de Recherche Sciences de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Richard B. Yapi
- 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
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Prisca B. Ndri
- 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 Nature, Université Nangui Abrogoua, 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
| | - Gotianwa Soro
- Programme National de Santé Scolaire et Universitaire, Abidjan, Côte d'Ivoire
| | - Ferdinand N. Kouamé
- Programme National de Santé Scolaire et Universitaire, Abidjan, Côte d'Ivoire
| | - Thomas Fürst
- Centre for Health Policy, Imperial College London, London, United Kingdom
- Department of Infectious Disease Epidemiology, 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
| | - 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
| | - 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
- * E-mail:
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