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Intirach J, Shu C, Lv X, Gao S, Sutthanont N, Chen T, Lv Z. Human parasitic infections of the class Adenophorea: global epidemiology, pathogenesis, prevention and control. Infect Dis Poverty 2024; 13:48. [PMID: 38902844 PMCID: PMC11188577 DOI: 10.1186/s40249-024-01216-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 06/07/2024] [Indexed: 06/22/2024] Open
Abstract
BACKGROUND Human parasitic infections caused by Adenophorean nematodes encompass a range of diseases, including dioctophymiasis, trichuriasis, capillariasis, trichinellosis, and myositis. These infection can result in adverse impacts on human health and cause societal and economic concerns in tropical and subtropical regions. METHODS This review conducted searches in PubMed, Embase and Google Scholar for relevant studies that published in established databases up to April 26, 2024. Studies that focused on the common morphology, life cycle, disease distribution, clinical manifestations, and prevention and control strategies for Adenophorean parasitic diseases in humans were included. RESULTS Adenophorean nematodes exhibit shared morphological characteristics with a four-layered cuticle; uninucleate epidermal cells; pseudocoelom with six or more coelomocytes; generally three caudal glands; five esophageal glands; two testes in males with median-ventral supplementary glands in a single row; tail in males rarely possessing caudal alae; amphids always postlabial; presence of cephalic sensory organs; absence of phasmids; and a secretory-excretory system consisting of a single ventral gland cell, usually with a non-cuticularized terminal duct. Humans play two important roles in the life cycle of the nematode class, Adenophorea: 1) as a definitive host infected by ingesting undercooked paratenic hosts, embryonated eggs, infective larvae in fish tissue and meat contaminated with encysted or non-encysted larvae, and 2) as an accidental host infected by ingesting parasitic eggs in undercooked meat. Many organs are targeted by the Adenophorean nematode in humans such as the intestines, lungs, liver, kidneys, lymphatic circulation and blood vessels, resulting in gastrointestinal problems, excessive immunological responses, cell disruption, and even death. Most of these infections have significant incidence rates in the developing countries of Africa, Asia and Latin America; however, some parasitic diseases have restricted dissemination in outbreaks. To prevent these diseases, interventions together with education, sanitation, hygiene and animal control measures have been introduced in order to reduce and control parasite populations. CONCLUSIONS The common morphology, life cycle, global epidemiology and pathology of human Adenophorean nematode-borne parasitic diseases were highlighted, as well as their prevention and control. The findings of this review will contribute to improvement of monitoring and predicting human-parasitic infections, understanding the relationship between animals, humans and parasites, and preventing and controlling parasitic diseases.
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Affiliation(s)
- Jitrawadee Intirach
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, Hainan, 570100, China
| | - Chang Shu
- School of Basic Medical Sciences and Life Sciences, Hainan Medical University, Haikou, Hainan, 571199, China
| | - Xin Lv
- School of Public Health, Hainan Medical University, Haikou, Hainan, 571199, China
| | - Suzhen Gao
- School of Public Health, Hainan Medical University, Haikou, Hainan, 571199, China
| | - Nataya Sutthanont
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Tao Chen
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, Hainan, 570100, China.
- Hainan Provincial Bureau of Disease Prevention and Control, Haikou, 570100, China.
| | - Zhiyue Lv
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, Hainan, 570100, China.
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, China.
- Key Laboratory of Tropical Disease Control (Sun Yat-Sen University), Ministry of Education, Guangzhou, Guangdong, 510080, China.
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Optimizing Implementation of Preventive Chemotherapy against Soil-Transmitted Helminthiasis and Intestinal Schistosomiasis Using High-Resolution Data: Field-Based Experiences from Côte d’Ivoire. Diseases 2022; 10:diseases10040066. [PMID: 36278565 PMCID: PMC9590038 DOI: 10.3390/diseases10040066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/07/2022] [Accepted: 09/14/2022] [Indexed: 11/17/2022] Open
Abstract
Background: Despite efforts to control neglected tropical diseases (NTDs) using preventive chemotherapy (PC), soil-transmitted helminthiases and schistosomiasis remain widely prevalent in sub-Saharan Africa. The current PC regimen in endemic settings is defined based on health district-level prevalence. This work aims to highlight the need for high-resolution data when elimination, rather than morbidity control, is the targeted goal. Methodology: Cross-sectional parasitological surveys were conducted from July to August 2019 and from September to October 2019, respectively, across the entire Dabou and Jacqueville health districts in southern Côte d’Ivoire. From every village, 60 school-aged children (6–15 years) were randomly selected and invited to provide one fresh stool sample, whereof duplicate Kato–Katz thick smears were prepared and read by two independent technicians. Principal Findings: 4338 school-aged children from 77 villages were screened from the Dabou (n = 2174; 50.12%, 39 villages) and Jacqueville (n = 2164; 49.88%, 38 villages) health districts. The prevalence of any soil-transmitted helminth (STH) infection was 12.47% and 11.09% in the Dabou and Jacqueville health districts, respectively. Species-specific district-level prevalence remained below 10%, varying between 0.51% (hookworm in Jacqueville) and 9.06% (Trichuris trichiura in Dabou). However, when considering sub-districts or villages only, several STH infection hotspots (five sub-districts with ≥20% and four villages with more than 50% infected) were observed. Schistosoma mansoni infection was found in less than 1% of the examined children in each health district. Conclusions/Significance: We conclude that keeping health district-level prevalence as a reference for PC implementation leaves many high-risk sub-districts or villages requiring PC (≥20% prevalence) untreated. To avoid maintaining those high-risk villages as STH reservoirs by skipping control interventions and jeopardizing the successes already achieved in STH control through PC during the past two decades, precision mapping is required. Further investigation is needed to assess cost-efficient approaches to implement small-scale disease surveillance.
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Aruni Chura J, Macchioni F, Furzi F, Balboa V, Mercado É, Gómez J, Rojas Gonzales P, Poma V, Loup A, Roselli M, Halkier P, Montresor A, Olliaro P, Bartoloni A, Spinicci M, Gabrielli S. Cross-sectional study on intestinal parasite infections in different ecological zones of the Department of La Paz, Bolivia. One Health 2021; 13:100271. [PMID: 34159246 PMCID: PMC8203811 DOI: 10.1016/j.onehlt.2021.100271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 05/18/2021] [Accepted: 05/25/2021] [Indexed: 11/13/2022] Open
Abstract
We performed a cross-sectional parasitological survey to assess the prevalence of protozoa and helminth infection among 275 school-age children (SAC) living in rural and peri-urban areas located in different ecological zones of the Department of La Paz, Bolivia. Public health activities for the control of STH, based on the biannual administration of mebendazole to preschool and school children are implemented at national level since 1986. We found an overall prevalence of 82.2% for intestinal parasites, including protozoa (80%) and helminths (23.3%). Blastocystis and Entamoeba coli were the most prevalent protozoa (found in 44% and 20.7% of the SAC enrolled); as for helminths, Ascaris lumbricoides and Hymenolepis nana were diagnosed in 14.5% and 3.3% of the children, respectively, followed by Trichuris trichiura 1.4%, Enterobius vermicularis 1.4%, Strongyloides stercoralis 0.7% and hookworms 0.7%. Molecular characterization of Blastocystis positive samples evidenced three different subtypes (ST1, ST2, ST3) highlighting the risk of transmission also from animal reservoir. We found a significant difference in the distribution of intestinal parasitic infection (IPIs) by ecological zone (44/74. 59% in Andean highlands, 94/170, 88% in tropical lowlands and 88/94, 94% in the Yungas, p < 0.001). Access to potable water (OR 0.1 95%CI 0.02–0.5, p = 0.004) and the habit of boiling drinking water (OR 0.3, 95% CI 0.2–0.7, p = 0.004) showed an independent association with a lower risk of all IPIs and STHs, respectively. The very low prevalence of STH infections of moderate heavy intensity demonstrate that periodical deworming has been successful in reducing the morbidity due to these parasites, however the high prevalence of protozoa demonstrate that sanitation is still problematic and there is a relevant contamination of the environment with human faeces. Significant efforts are still needed to reduce IPIs transmission and to improve health and sanitation in this area. In the Department of La Paz, the current overall STH among school-age children prevalence is high (17.1%), with a patchy distribution throughout the region. The prevalence of STH infections of moderate and heavy intensity shows that the morbidity due to these parasites has not been eliminated yet. The preventive chemotherapy coverage should be significantly improved in all the at-risk populations, and strategy of PC delivery should be tailored to local conditions. Updated epidemiological information is crucial to inform policy for STH control. Significant efforts are still needed to reduce transmission and to improve health and sanitation in this area. Interventions should be inspired by the WASH principles, endorsed by the WHO.
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Affiliation(s)
- Jorge Aruni Chura
- Instituto Nacional de Laboratorios de Salud (INLASA) - Ministerio de Salud, La Paz, Plurinational State of Bolivia
| | - Fabio Macchioni
- Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy
| | - Federica Furzi
- Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma Sapienza, Roma, Italy
| | - Victor Balboa
- Instituto Nacional de Laboratorios de Salud (INLASA) - Ministerio de Salud, La Paz, Plurinational State of Bolivia
| | - Érika Mercado
- Instituto Nacional de Laboratorios de Salud (INLASA) - Ministerio de Salud, La Paz, Plurinational State of Bolivia
| | - José Gómez
- Instituto Nacional de Laboratorios de Salud (INLASA) - Ministerio de Salud, La Paz, Plurinational State of Bolivia
| | | | - Veronica Poma
- Escuela de Salud del Chaco Tekove Katu, Gutierrez, Plurinational State of Bolivia
| | - Armando Loup
- Ministerio de Salud, Programa Nacional de Zoonosis, La Paz, Plurinational State of Bolivia
| | - Mimmo Roselli
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Percy Halkier
- Immunization, Pan-American Health Organization, La Paz, Plurinational State of Bolivia
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Piero Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Alessandro Bartoloni
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Michele Spinicci
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Simona Gabrielli
- Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma Sapienza, Roma, Italy
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Vegvari C, Giardina F, Bajaj S, Malizia V, Hardwick RJ, Truscott JE, Montresor A, de Vlas SJ, Coffeng LE, Anderson RM. Deworming women of reproductive age during adolescence and pregnancy: what is the impact on morbidity from soil-transmitted helminths infection? Parasit Vectors 2021; 14:220. [PMID: 33892750 PMCID: PMC8063329 DOI: 10.1186/s13071-021-04620-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 02/01/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Soil-transmitted helminths (STHs) are a major cause of poor health in low- and middle-income countries. In particular, hookworm is known to cause anaemia in children and women of reproductive age (WRA). One goal of the World Health Organization's (WHO) 2030 roadmap for neglected tropical diseases is to reduce STH-related morbidity in WRA. As a minimal intervention, the WHO recommends deworming adolescent girls annually during human papilloma virus vaccination programmes and WRA during pregnancy and lactation. These routine interventions are low cost and can be implemented even by the most basic health services in endemic countries. In this study we use a cohort model to investigate the potential impact on STH-related morbidity in WRA. RESULTS Annual deworming treatment of adolescent girls reduces the prevalence of moderate- and heavy-intensity infections in this age group by up to 60% in moderate transmission settings and by 12-27% in high transmission settings. Treatment of WRA during pregnancy and lactation on its own has a small (< 20%) but significant effect on morbidity although it does not lead to the achievement of the morbidity target (< 2% moderate- to high-intensity infections) in this age group. However, depending on the age-intensity profile of infection, which may vary geographically, and assumptions on the density-dependence of egg production by fertilised female worms, continued school-based treatment may be able to reduce the force of infection acting on WRA, both through an indirect effect on the overall population-based force of infection and via reducing the burden of infection as children age and move into the WRA age classes. As a result, morbidity in WRA may be eliminated. CONCLUSION While deworming during pregnancy and lactation does not lead to the achievement of the morbidity target in WRA and its efficacy may vary by setting, it is still expected to be beneficial for maternity and child health. Monitoring of any WRA-based intervention is recommended to evaluate its effectiveness.
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Affiliation(s)
- Carolin Vegvari
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK.
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK.
- Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK.
| | - Federica Giardina
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sumali Bajaj
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Veronica Malizia
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Robert J Hardwick
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
- The DeWorm3 Project, The Natural History Museum of London, London, SW7 5BD, UK
| | - James E Truscott
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
- The DeWorm3 Project, The Natural History Museum of London, London, SW7 5BD, UK
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Sake J de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Luc E Coffeng
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Roy M Anderson
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, St Mary's Campus, Praed Street, London, W2 1PG, UK
- Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
- The DeWorm3 Project, The Natural History Museum of London, London, SW7 5BD, UK
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Montresor A, Mupfasoni D, Mikhailov A, Mwinzi P, Lucianez A, Jamsheed M, Gasimov E, Warusavithana S, Yajima A, Bisoffi Z, Buonfrate D, Steinmann P, Utzinger J, Levecke B, Vlaminck J, Cools P, Vercruysse J, Cringoli G, Rinaldi L, Blouin B, Gyorkos TW. The global progress of soil-transmitted helminthiases control in 2020 and World Health Organization targets for 2030. PLoS Negl Trop Dis 2020; 14:e0008505. [PMID: 32776942 PMCID: PMC7446869 DOI: 10.1371/journal.pntd.0008505] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 08/20/2020] [Accepted: 06/19/2020] [Indexed: 11/29/2022] Open
Abstract
Soil-transmitted helminth (STH) infections are the most widespread of the neglected tropical diseases, primarily affecting marginalized populations in low- and middle-income countries. More than one billion people are currently infected with STHs. For the control of these infections, the World Health Organization (WHO) recommends an integrated approach, which includes access to appropriate sanitation, hygiene education, and preventive chemotherapy (i.e., large-scale, periodic distribution of anthelmintic drugs). Since 2010, WHO has coordinated two large donations of benzimidazoles to endemic countries. Thus far, more than 3.3 billion benzimidazole tablets have been distributed in schools for the control of STH infections, resulting in an important reduction in STH-attributable morbidity in children, while additional tablets have been distributed for the control of lymphatic filariasis. This paper (i) summarizes the progress of global STH control between 2008 to 2018 (based on over 690 reports submitted by endemic countries to WHO); (ii) provides regional and country details on preventive chemotherapy coverage; and (iii) indicates the targets identified by WHO for the next decade and the tools that should be developed to attain these targets. The main message is that STH-attributable morbidity can be averted with evidence-informed program planning, implementation, and monitoring. Caution will still need to be exercised in stopping control programs to avoid any rebound of prevalence and loss of accrued morbidity gains. Over the next decade, with increased country leadership and multi-sector engagement, the goal of eliminating STH infections as a public health problem can be achieved.
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Affiliation(s)
- Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Denise Mupfasoni
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Alexei Mikhailov
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Pauline Mwinzi
- Expanded Special Programme for Elimination of Neglected Tropical Diseases, World Health Organization, Regional Office for Africa, Brazzaville, Congo
| | - Ana Lucianez
- Neglected, Tropical and Vector Borne Diseases, World Health Organization Regional Office for the Americas, Washington, United States of America
| | - Mohamed Jamsheed
- Neglected Tropical Disease Control, World Health Organization, Regional Office for South-East Asia, New Delhi, India
| | - Elkan Gasimov
- Malaria, NTDs and other Vector-Borne Diseases, World Health Organization, Regional Office for Europe, Copenhagen, Denmark
| | - Supriya Warusavithana
- Control of Communicable Diseases, World Health Organization, Regional Office for Eastern Mediterranean, Cairo, Egypt
| | - Aya Yajima
- Malaria, other Vectorborne and Parasitic Diseases, World Health Organization, Regional Office for Western Pacific, Manila, The Philippines
| | - Zeno Bisoffi
- Department of Infectious–Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Verona, Italy (WHO Collaborating Centre ITA-102)
| | - Dora Buonfrate
- Department of Infectious–Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Verona, Italy (WHO Collaborating Centre ITA-102)
| | - Peter Steinmann
- Swiss Tropical and Public Health Institute, Basel, Switzerland (WHO Collaborating Centre SWI-71)
- University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland (WHO Collaborating Centre SWI-71)
- University of Basel, Basel, Switzerland
| | - Bruno Levecke
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Sciences, Ghent University, Merelbeke, Belgium (WHO Collaborating Centre BEL-42)
| | - Johnny Vlaminck
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Sciences, Ghent University, Merelbeke, Belgium (WHO Collaborating Centre BEL-42)
| | - Piet Cools
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Sciences, Ghent University, Merelbeke, Belgium (WHO Collaborating Centre BEL-42)
| | - Jozef Vercruysse
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Sciences, Ghent University, Merelbeke, Belgium (WHO Collaborating Centre BEL-42)
| | - Giuseppe Cringoli
- Laboratory of Parasitology and Parasitic Diseases, Department of Veterinary Medicine and Animal Production. University of Naples, Naples, Italy (WHO Collaborating Centre ITA-116)
| | - Laura Rinaldi
- Laboratory of Parasitology and Parasitic Diseases, Department of Veterinary Medicine and Animal Production. University of Naples, Naples, Italy (WHO Collaborating Centre ITA-116)
| | - Brittany Blouin
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada (WHO Collaborating Centre CAN-88)
| | - Theresa W. Gyorkos
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada (WHO Collaborating Centre CAN-88)
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Partridge FA, Forman R, Bataille CJR, Wynne GM, Nick M, Russell AJ, Else KJ, Sattelle DB. Anthelmintic drug discovery: target identification, screening methods and the role of open science. Beilstein J Org Chem 2020; 16:1203-1224. [PMID: 32550933 PMCID: PMC7277699 DOI: 10.3762/bjoc.16.105] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022] Open
Abstract
Helminths, including cestodes, nematodes and trematodes, are a huge global health burden, infecting hundreds of millions of people. In many cases, existing drugs such as benzimidazoles, diethylcarbamazine, ivermectin and praziquantel are insufficiently efficacious, contraindicated in some populations, or at risk of the development of resistance, thereby impeding progress towards World Health Organization goals to control or eliminate these neglected tropical diseases. However, there has been limited recent progress in developing new drugs for these diseases due to lack of commercial attractiveness, leading to the introduction of novel, more efficient models for drug innovation that attempt to reduce the cost of research and development. Open science aims to achieve this by encouraging collaboration and the sharing of data and resources between organisations. In this review we discuss how open science has been applied to anthelmintic drug discovery. Open resources, including genomic information from many parasites, are enabling the identification of targets for new antiparasitic agents. Phenotypic screening remains important, and there has been much progress in open-source systems for compound screening with parasites, including motility assays but also high content assays with more detailed investigation of helminth physiology. Distributed open science compound screening programs, such as the Medicines for Malaria Venture Pathogen Box, have been successful at facilitating screening in diverse assays against many different parasite pathogens and models. Of the compounds identified so far in these screens, tolfenpyrad, a repurposed insecticide, shows significant promise and there has been much progress in creating more potent and selective derivatives. This work exemplifies how open science approaches can catalyse drug discovery against neglected diseases.
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Affiliation(s)
- Frederick A Partridge
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Ruth Forman
- The Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Carole J R Bataille
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
| | - Graham M Wynne
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
| | - Marina Nick
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Angela J Russell
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, United Kingdom
| | - Kathryn J Else
- The Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - David B Sattelle
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
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Estimated need for anthelminthic medicines to control soil-transmitted helminthiases in school-aged children, 2020-2030. Infect Dis Poverty 2020; 9:48. [PMID: 32381061 PMCID: PMC7204277 DOI: 10.1186/s40249-020-00656-9] [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: 11/11/2019] [Accepted: 04/06/2020] [Indexed: 11/24/2022] Open
Abstract
Background Soil-transmitted helminthiases (STH) are part of the group of neglected tropical diseases traditionally treated with preventive chemotherapy interventions. In recent years, drug donations have been essential to expanding preventive chemotherapy and achieving progressive control of morbidity from STH. This study aims to evaluate the need for anthelminthic medicines during 2020–2030. Methods To estimate the need for anthelminthic medicines, we considered three different scenarios: (1) the control programmes continues to expand coverage and maintains the frequency of drug administration established at baseline; (2) the programmes continues to expand coverage but adapts the frequency of drug administration when the STH prevalence is reduced and (3) the STH programme becomes self-sustainable in some endemic countries. Results We estimate that the number of anthelmintic medicines needed to treat school-aged children will increase by 40% by 2025 and by 52% by 2030 if countries do not change the frequency of preventive chemotherapy (scenario 1); that the number of tablets needed will reduce by 32.4% by 2025 and by 49.1% in 2030 if endemic countries reduce the frequency of preventive chemotherapy (scenario 2); and drug donations could be reduced by 54.4% by 2025 and 74.4% by 2030 if some endemic countries could become independent in drug procurement (scenario 3). Conclusions The number of anthelmintic medicines needed to achieve elimination of morbidity due to STH in school-aged children will decline during 2020–2030. The decline will be substantial if a number of “upper-middle income” countries in which STH are endemic procure, as expected, anthelminthic medicines independently.
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Patel C, Coulibaly JT, Schulz JD, N'Gbesso Y, Hattendorf J, Keiser J. Efficacy and safety of ascending dosages of albendazole against Trichuris trichiura in preschool-aged children, school-aged children and adults: A multi-cohort randomized controlled trial. EClinicalMedicine 2020; 22:100335. [PMID: 32405623 PMCID: PMC7210508 DOI: 10.1016/j.eclinm.2020.100335] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND The efficacy of the widely used albendazole against the soil-transmitted helminth Trichuris trichiura is limited; yet optimal doses, which may provide increased efficacy, have not been thoroughly investigated to date. METHODS A randomized-controlled trial was conducted in Côte d'Ivoire with preschool-aged children (PSAC), school-aged children (SAC), and adults infected with T. trichiura. Participants were randomly assigned (1:1:1:1) using computer-generated randomization. PSAC were randomized to 200 mg, 400 mg, 600 mg of albendazole or placebo. SAC and adults were randomized to 400 mg, 600 mg, 800 mg of albendazole or placebo. The primary outcome was cure rates (CRs) against trichuriasis. Secondary outcomes were T. trichiura egg reduction rates (ERRs), safety, CRs and ERRs against other soil-transmitted helminths. Outcome assessors and the trial statistician were blinded. Trial registration at ClinicalTrial.gov: NCT03527745. FINDINGS 111 PSAC, 180 SAC, and 42 adults were randomized and 86, 172, and 35 provided follow-up stool samples, respectively. The highest observed CR among PSAC was 27·8% (95% CI: 9·7%-53·5%) in the 600 mg albendazole treatment arm. The most efficacious arm for SAC was 600 mg of albendazole showing a CR of 25·6% (95% CI: 13·5%-41·2%), and for adults it was 400 mg of albendazole with a CR of 55·6% (95% CI: 21·2%-86·3%). CRs and ERRs did not differ significantly among treatment arms and flat dose-responses were observed. 17·9% and 0·4% of participants reported any adverse event at 3 and 24 h follow-up, respectively. INTERPRETATION Albendazole shows low efficacy against T. trichiura in all populations and doses studied, though findings for PSAC and adults should be carefully interpreted as recruitment targets were not met. New drugs, treatment regimens, and combinations are needed in the management of T. trichiura infections. FUNDING Bill and Melinda Gates Foundation.
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Affiliation(s)
- Chandni Patel
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jean T. Coulibaly
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire and Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Jessica D. Schulz
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Yves N'Gbesso
- Department de Agboville, Centre de Santé Urbain d'Azaguié, Côte d'Ivoire
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Corresponding author.
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9
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Mupfasoni D, Bangert M, Mikhailov A, Marocco C, Montresor A. Sustained preventive chemotherapy for soil-transmitted helminthiases leads to reduction in prevalence and anthelminthic tablets required. Infect Dis Poverty 2019; 8:82. [PMID: 31575378 PMCID: PMC6774215 DOI: 10.1186/s40249-019-0589-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/14/2019] [Indexed: 11/27/2022] Open
Abstract
Background The goal of soil-transmitted helminthiases (STH) control programmes is to eliminate STH-associated morbidity in the target population by reducing the prevalence of moderate- and heavy-intensity infections and the overall STH infection prevalence mainly through preventive chemotherapy (PC) with either albendazole or mebendazole. Endemic countries should measure the success of their control programmes through regular epidemiological assessments. We evaluated changes in STH prevalence in countries that conducted effective PC coverage for STH to guide changes in the frequency of PC rounds and the number of tablets needed. Methods We selected countries from World Health Organization (WHO)‘s Preventive Chemotherapy and Transmission control (PCT) databank that conducted ≥5 years of PC with effective coverage for school-age children (SAC) and extracted STH baseline and impact assessment data using the WHO Epidemiological Data Reporting Form, Ministry of Health reports and/or peer-reviewed publications. We used pooled and weighted means to plot the prevalence of infection with any STH and with each STH species at baseline and after ≥5 years of PC with effective coverage. Finally, using the WHO STH decision tree, we estimated the reduction in the number of tablets needed. Results Fifteen countries in four WHO regions conducted annual or semi-annual rounds of PC for STH for 5 years or more and collected data before and after interventions. At baseline, the pooled prevalence was 48.9% (33.1–64.7%) for any STH, 23.2% (13.7–32.7%) for Ascaris lumbricoides, 21.01% (9.7–32.3%) for Trichuris trichiura and 18.2% (10.9–25.5%) for hookworm infections, while after ≥5 years of PC for STH, the prevalence was 14.3% (7.3–21.3%) for any STH, 6.9% (1.3–12.5%) for A. lumbricoides, 5.3% (1.06–9.6%) for T. trichiura and 8.1% (4.0–12.2%) for hookworm infections. Conclusions Countries endemic for STH have made tremendous progress in reducing STH-associated morbidity, but very few countries have data to demonstrate that progress. In this study, the data show that nine countries should adapt their PC strategies and the frequency of PC rounds to yield a 36% reduction in drug needs. The study also highlights the importance of impact assessment surveys to adapt control strategies according to STH prevalence. Electronic supplementary material The online version of this article (10.1186/s40249-019-0589-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Denise Mupfasoni
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland.
| | - Mathieu Bangert
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Alexei Mikhailov
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Chiara Marocco
- 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
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10
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Cools P, Vlaminck J, Albonico M, Ame S, Ayana M, José Antonio BP, Cringoli G, Dana D, Keiser J, Maurelli MP, Maya C, Matoso LF, Montresor A, Mekonnen Z, Mirams G, Corrêa-Oliveira R, Pinto SA, Rinaldi L, Sayasone S, Thomas E, Verweij JJ, Vercruysse J, Levecke B. Diagnostic performance of a single and duplicate Kato-Katz, Mini-FLOTAC, FECPAKG2 and qPCR for the detection and quantification of soil-transmitted helminths in three endemic countries. PLoS Negl Trop Dis 2019; 13:e0007446. [PMID: 31369558 PMCID: PMC6675048 DOI: 10.1371/journal.pntd.0007446] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/07/2019] [Indexed: 12/20/2022] Open
Abstract
Background Because the success of deworming programs targeting soil-transmitted helminths (STHs) is evaluated through the periodically assessment of prevalence and infection intensities, the use of the correct diagnostic method is of utmost importance. The STH community has recently published for each phase of a deworming program the minimal criteria that a potential diagnostic method needs to meet, the so-called target product profiles (TPPs). Methodology We compared the diagnostic performance of a single Kato-Katz (reference method) with that of other microscopy-based methods (duplicate Kato-Katz, Mini-FLOTAC and FECPAKG2) and one DNA-based method (qPCR) for the detection and quantification of STH infections in three drug efficacy trials in Ethiopia, Lao PDR, and Tanzania. Furthermore, we evaluated a selection of minimal diagnostic criteria of the TPPs. Principal findings All diagnostic methods showed a clinical sensitivity of ≥90% for all STH infections of moderate-to-heavy intensities. For infections of very low intensity, only qPCR resulted in a sensitivity that was superior to a single Kato-Katz for all STHs. Compared to the reference method, both Mini-FLOTAC and FECPAKG2 resulted in significantly lower fecal egg counts for some STHs, leading to a substantial underestimation of the infection intensity. For qPCR, there was a positive significant correlation between the egg counts of a single Kato-Katz and the DNA concentration. Conclusions/Significance Our results indicate that the diagnostic performance of a single Kato-Katz is underestimated by the community and that diagnostic specific thresholds to classify intensity of infection are warranted for Mini-FLOTAC, FECPAKG2 and qPCR. When we strictly apply the TPPs, Kato-Katz is the only microscopy-based method that meets the minimal diagnostic criteria for application in the planning, monitoring and evaluation phase of an STH program. qPCR is the only method that could be considered in the phase that aims to seek confirmation for cessation of program. Trial registration ClinicalTrials.gov NCT03465488 To control the burden caused by intestinal worms, the World Health Organization recommends large-scale deworming programs where anti-worm drugs are administered to at-risk populations. The decision to scale down drug distribution is based on the periodically assessment of prevalence and intensity of infections using a standard diagnostic method. Today, the scientific community strongly doubts whether this method can be used throughout the program. This is in particular when it fails to detect infections of low intensity, and hence may result in prematurely stopping the distribution of drugs. We compared the diagnostic performance of alternative diagnostic methods in three drug efficacy trials in two African and one Asian country. The diagnostic methods were based on demonstration of worm eggs or worm DNA in stool. We also checked the results with minimal diagnostic criteria which have been recently been proposed by the scientific community. Our results indicate that of all diagnostic methods based on demonstration of worm eggs, only the current standard method fulfills the diagnostic criteria for planning, monitoring and evaluation phases of deworming program. Furthermore, we showed that DNA-based methods could be considered in the phase that aims to seek confirmation for cessation of the deworming program.
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Affiliation(s)
- Piet Cools
- Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| | - Johnny Vlaminck
- Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| | - Marco Albonico
- Center for Tropical Diseases, Sacro Cuore Don Calabria Hospital, Negrar, Italy
- Department of Life Sciences and Systems Biology, University of Turin, Italy
| | - Shaali Ame
- Public Health Laboratory-Ivo de Carneri, Chake Chake, United Republic of Tanzania
| | - Mio Ayana
- Jimma University Institute of Health, Jimma University, Jimma, Ethiopia
| | | | - Giuseppe Cringoli
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Daniel Dana
- Jimma University Institute of Health, Jimma University, Jimma, Ethiopia
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Maria P. Maurelli
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Catalina Maya
- Engineering Institute of National Autonomous University of Mexico, Mexico City, Mexico
| | - Leonardo F. Matoso
- Laboratory of Molecular and Cellular Immunology, Research Center René Rachou—FIOCRUZ, Belo Horizonte, Brazil
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Zeleke Mekonnen
- Jimma University Institute of Health, Jimma University, Jimma, Ethiopia
| | | | - Rodrigo Corrêa-Oliveira
- Laboratory of Molecular and Cellular Immunology, Research Center René Rachou—FIOCRUZ, Belo Horizonte, Brazil
| | - Simone A. Pinto
- Laboratory of Molecular and Cellular Immunology, Research Center René Rachou—FIOCRUZ, Belo Horizonte, Brazil
| | - Laura Rinaldi
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Somphou Sayasone
- Lao Tropical and Public Health Institute, Ministry of Health, Vientiane, Lao People’s Democratic Republic
| | | | - Jaco J. Verweij
- Laboratory for Medical Microbiology and Immunology, Elisabeth-Tweesteden Hospital, Tilburg, The Netherlands
| | - Jozef Vercruysse
- Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| | - Bruno Levecke
- Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
- * E-mail:
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11
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Freeman MC, Akogun O, Belizario V, Brooker SJ, Gyorkos TW, Imtiaz R, Krolewiecki A, Lee S, Matendechero SH, Pullan RL, Utzinger J. Challenges and opportunities for control and elimination of soil-transmitted helminth infection beyond 2020. PLoS Negl Trop Dis 2019; 13:e0007201. [PMID: 30973872 PMCID: PMC6459486 DOI: 10.1371/journal.pntd.0007201] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Matthew C. Freeman
- Department of Environmental Health, Emory University, Atlanta, Georgia, United States of America
| | | | - Vicente Belizario
- College of Public Health, University of the Philippines Manila, Manila, the Philippines
| | - Simon J. Brooker
- Global Health, Bill & Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Theresa W. Gyorkos
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Rubina Imtiaz
- Children Without Worms, The Task Force for Global Health, Decatur, Georgia, United States of America
| | - Alejandro Krolewiecki
- Instituto de Investigaciones en Enfermedades Tropicales, Universidad Nacional de Salta, Oran, Argentina
| | - Seung Lee
- Save the Children, Washington, DC, United States of America
| | | | - Rachel L. Pullan
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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12
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Montresor A, Trouleau W, Mupfasoni D, Bangert M, Joseph SA, Mikhailov A, Fitzpatrick C. Preventive chemotherapy to control soil-transmitted helminthiasis averted more than 500 000 DALYs in 2015. Trans R Soc Trop Med Hyg 2018; 111:457-463. [PMID: 29346640 DOI: 10.1093/trstmh/trx082] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/19/2017] [Indexed: 01/04/2023] Open
Abstract
Background Preventive chemotherapy (PC), the large-scale administration of anthelminthics, is recommended by the World Health Organization (WHO) for the control of soil-transmitted helminthiasis (STH). Since 2010, donated anthelminthics for STH have boosted the implementation of PC programmes in children, achieving global coverage of more than 60% in 2015. The WHO Global Health Estimates attribute an annual loss of over 3.3 million disability-adjusted life-years (DALYs) to STH. The aim of this study is to estimate the impact of PC programmes on child morbidity. Method We used data from the WHO Global Health Estimates, national coverage data on PC and the results of an evaluation of the impact of PC in 17 countries on morbidity previously conducted by our group. Results We estimated that the implementation of PC averted in 2015 over 44% of the DALYs that would have been caused in children by STH without the control intervention. A reduction in morbidity of over 75% is expected, if the global target is reached in 2020. If the programme is subsequently maintained, morbidity from STH will be almost totally removed by 2025. Conclusions In endemic areas, preventive chemotherapy provides a significant health benefit. We consider this estimation potentially useful to evaluate the cost utility of the investment made by several endemic countries on PC to control STH.
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Affiliation(s)
- A Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
| | - W Trouleau
- School of Computer and Communication Sciences, EPFL, Lausanne, Switzerland
| | - D Mupfasoni
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
| | - M Bangert
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
| | - S A Joseph
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
| | - A Mikhailov
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
| | - C Fitzpatrick
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva
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13
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Debaveye S, Gonzalez Torres CV, De Smedt D, Heirman B, Kavanagh S, Dewulf J. The public health benefit and burden of mass drug administration programs in Vietnamese schoolchildren: Impact of mebendazole. PLoS Negl Trop Dis 2018; 12:e0006954. [PMID: 30419030 PMCID: PMC6258429 DOI: 10.1371/journal.pntd.0006954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 11/26/2018] [Accepted: 10/29/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Mass anthelmintic drug administration is recommended in developing countries to address infection by soil-transmitted helminthiases (STH). We quantified the public health benefit of treatment with mebendazole in eight million Vietnamese children aged 5-14 years from 2006 to 2011. This was compared to the environmental impact of the pharmaceutical supply chain of mebendazole, as the resource use and emissions associated with pharmaceutical production can be associated with a public health burden, e.g. through emissions of fine particulate matter. METHODOLOGY Through Markov modelling the disability due to STH was quantified for hookworm, Ascaris lumbricoides and Trichuris trichiura. For each worm type, four levels of intensity of infection were included: none, light, medium and heavy. The treatment effect on patients was quantified in Disability-Adjusted Life Years (DALYs). The public health burden induced by the pharmaceutical supply chain of mebendazole was quantified in DALYs through Life Cycle Assessment. PRINCIPAL FINDINGS Compared to 'no treatment', the modelled results of five-year treatment averted 116,587 DALYs (68% reduction) for the three worms combined and largely driven by A. lumbricoides. The main change in DALYs occurred in the first year of treatment, after which the results stabilized. The public health burden associated with the pharmaceutical supply chain was 6 DALYs. CONCLUSIONS The public health benefit of the Mass Drug Administration (MDA) averted substantially more DALYs than those induced by the pharmaceutical supply chain. These results were verified in a sensitivity analysis. The starting prevalence for each worm was the most sensitive model parameter. This methodology is useful for policymakers interested in a holistic approach towards the public health performance of MDA programs, enveloping both the treatment benefit received by the patient and the public health burden associated with the resource consumption and environmental emissions of the pharmaceutical production and supply chain.
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Affiliation(s)
- Sam Debaveye
- Department of Green Chemistry and Technology, Ghent University, Campus Coupure, Ghent, Belgium
| | | | - Delphine De Smedt
- Department of Public Health, Ghent University, Campus UZ, Ghent, Belgium
| | - Bert Heirman
- Johnson & Johnson EHS&S, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Shane Kavanagh
- Health Economics, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Jo Dewulf
- Department of Green Chemistry and Technology, Ghent University, Campus Coupure, Ghent, Belgium
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14
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Booth M, Clements A. Neglected Tropical Disease Control - The Case for Adaptive, Location-specific Solutions. Trends Parasitol 2018; 34:272-282. [PMID: 29500033 DOI: 10.1016/j.pt.2018.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 02/07/2023]
Abstract
The world is experiencing environmental and social change at an unprecedented rate, with the effects being felt at local, regional, and international scales. This phenomenon may disrupt interventions against neglected tropical diseases (NTDs) that operate on the basis of linear scaling and 'one-size-fits-all'. Here we argue that investment in field-based data collection and building modelling capacity is required; that it is important to consider unintended consequences of interventions; that inferences can be drawn from wildlife ecology; and that interventions should become more location-specific. Collectively, these ideas underpin the development of adaptive decision-support tools that are sufficiently flexible to address emerging issues within the Anthropocene.
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Affiliation(s)
- Mark Booth
- Faculty of Medical Sciences, Newcastle University, UK.
| | - Archie Clements
- Research School of Population Health, Australian National University, Australia
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15
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A´sbjo¨rnsdo´ttir KH, Means AR, Werkman M, Walson JL. Prospects for elimination of soil-transmitted helminths. Curr Opin Infect Dis 2017; 30:482-488. [PMID: 28700363 PMCID: PMC7680933 DOI: 10.1097/qco.0000000000000395] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW Soil-transmitted helminths (STH) are endemic in 120 countries and are associated with substantial morbidity and loss of economic productivity. Although current WHO guidelines focus on morbidity control through mass drug administration (MDA), there is global interest in whether a strategy targeting disease elimination might be feasible in some settings. This review summarizes the prospects for switching from control to an elimination strategy. RECENT FINDINGS STH control efforts have reduced the intensity of infections in targeted populations with associated reductions in morbidity. However, adults are not frequently targeted and remain important reservoirs for reinfection of treated children. Recent modeling suggests that transmission interruption may be possible through expanded community-wide delivery of MDA, the feasibility of which has been demonstrated by other programs. However, these models suggest that high levels of coverage and compliance must be achieved. Potential challenges include the risk of prematurely dismantling STH programs and the potential increased risk of antihelminthic resistance. SUMMARY Elimination of STH may offer an opportunity to eliminate substantial STH-related morbidity while reducing resource needs of neglected tropical disease programs. Evidence from large community trials is needed to determine the feasibility of interrupting the transmission of STH in some geographic settings.
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Affiliation(s)
- Kristjana H. A´sbjo¨rnsdo´ttir
- DeWorm3, The Natural History Museum, London, UK
- Department of Global Health, University of Washington, Seattle, Washington, USA and
| | - Arianna R. Means
- DeWorm3, The Natural History Museum, London, UK
- Department of Global Health, University of Washington, Seattle, Washington, USA and
| | - Marleen Werkman
- DeWorm3, The Natural History Museum, London, UK
- Department of Infectious Disease Epidemiology, London Centre for Neglected Tropical Disease Research (LCNTDR), St. Mary’s Campus, Imperial College London, London, UK
| | - Judd L. Walson
- DeWorm3, The Natural History Museum, London, UK
- Department of Global Health, University of Washington, Seattle, Washington, USA and
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Montresor A, King JD. Elimination of lymphatic filariasis in Loa loa areas. THE LANCET. INFECTIOUS DISEASES 2017; 17:683-684. [PMID: 28372976 PMCID: PMC5584658 DOI: 10.1016/s1473-3099(17)30163-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 03/10/2017] [Indexed: 06/07/2023]
Affiliation(s)
- Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Av Appia 20CH-1211, Geneva 27, Switzerland.
| | - Jonathan D King
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Av Appia 20CH-1211, Geneva 27, Switzerland
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17
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Jourdan PM, Montresor A, Walson JL. Building on the success of soil-transmitted helminth control - The future of deworming. PLoS Negl Trop Dis 2017; 11:e0005497. [PMID: 28426784 PMCID: PMC5398509 DOI: 10.1371/journal.pntd.0005497] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Judd L. Walson
- DeWorm3, Natural History Museum, London, United Kingdom
- Departments of Global Health, Internal Medicine (Allergy and Infectious Disease), Pediatrics and Epidemiology, University of Washington, Seattle, Washington, United States of America
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