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Bardosh K, Inthavong P, Xayaheuang S, Okello AL. Controlling parasites, understanding practices: the biosocial complexity of a One Health intervention for neglected zoonotic helminths in northern Lao PDR. Soc Sci Med 2014; 120:215-23. [PMID: 25261615 DOI: 10.1016/j.socscimed.2014.09.030] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 09/15/2014] [Accepted: 09/16/2014] [Indexed: 11/25/2022]
Abstract
A parasitological survey in northern Lao PDR showed a remote ethnic minority village to be hyper-endemic for Taenia solium, a Neglected Tropical Disease (NTD) that impacts human and pig health. An intervention combining human Mass Drug Administration (MDA) with porcine vaccination and antihelmintic treatment was then implemented, targeting both T. solium and other soil-transmitted helminths. To understand the biosocial complexity of this integrated One Health intervention, we conducted a rapid ethnographic study exploring the transmission dynamics of T. solium and locally acceptable long-term control options. Informed by two years of project work in the village, this included six focus group discussions, 35 semi-structured interviews, a latrine survey, a school-based education meeting, participant observation and many unstructured interviews conducted over two weeks in October 2013. We found that risk behaviours were mediated by various social determinants including limited market access, interrelationships between alcohol, ancestral sacrifices and the consumption of raw pork, seasonal variations and poor latrine coverage. Only sixteen percent of households had latrines, attributed to the unacceptability of dry latrines, lack of water access, poor building techniques and poverty. Whilst women could explain T. solium transmission, most men and children could not, revealing that distributed posters/leaflets relied too heavily on text and ambiguous images. Compliance with MDA was high due to trust between project staff and village leaders. However understandings of pharmacology, minor side effects, human migration and children's fear of worms may lead to resistance in future programmes. Our research highlights the complexities of controlling T. solium and other soil-transmitted helminths in a remote ethnic minority village and the need to integrate biomedical and participatory approaches. Although we showcase the heuristic value of using rapid ethnography to inform intervention strategies as part of a One Health/NTD agenda, we also identify several possible paradoxes and conundrums in embedding locally-grounded biosocial analysis into NTD programmes. These need to be acknowledged and negotiated by multidisciplinary teams.
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Affiliation(s)
- Kevin Bardosh
- School of Social and Political Science, The University of Edinburgh, 58 George Square, Edinburgh, United Kingdom; Division of Pathway Medicine and Centre for Infectious Diseases, School of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom.
| | - Phouth Inthavong
- National Animal Health Laboratory, Ministry of Agriculture and Forestry, Department of Livestock and Fisheries, Luang Prabang Road, Ban Huanmouang, Vientiane Capital, Lao Democratic People's Republic
| | - Sivilai Xayaheuang
- CSIRO Animal, Food and Health Sciences, Australian Animal Health Laboratory (AAHL) Regional Programme, 5 Portarlington Road, East Geelong, Victoria, Australia
| | - Anna L Okello
- National Animal Health Laboratory, Ministry of Agriculture and Forestry, Department of Livestock and Fisheries, Luang Prabang Road, Ban Huanmouang, Vientiane Capital, Lao Democratic People's Republic; CSIRO Animal, Food and Health Sciences, Australian Animal Health Laboratory (AAHL) Regional Programme, 5 Portarlington Road, East Geelong, Victoria, Australia
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Rebaudo F, Costa J, Almeida CE, Silvain JF, Harry M, Dangles O. Simulating population genetics of pathogen vectors in changing landscapes: guidelines and application with Triatoma brasiliensis. PLoS Negl Trop Dis 2014; 8:e3068. [PMID: 25102068 PMCID: PMC4125301 DOI: 10.1371/journal.pntd.0003068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/21/2014] [Indexed: 11/28/2022] Open
Abstract
Background Understanding the mechanisms that influence the population dynamics and spatial genetic structure of the vectors of pathogens infecting humans is a central issue in tropical epidemiology. In view of the rapid changes in the features of landscape pathogen vectors live in, this issue requires new methods that consider both natural and human systems and their interactions. In this context, individual-based model (IBM) simulations represent powerful yet poorly developed approaches to explore the response of pathogen vectors in heterogeneous social-ecological systems, especially when field experiments cannot be performed. Methodology/Principal Findings We first present guidelines for the use of a spatially explicit IBM, to simulate population genetics of pathogen vectors in changing landscapes. We then applied our model with Triatoma brasiliensis, originally restricted to sylvatic habitats and now found in peridomestic and domestic habitats, posing as the most important Trypanosoma cruzi vector in Northeastern Brazil. We focused on the effects of vector migration rate, maximum dispersal distance and attraction by domestic habitat on T. brasiliensis population dynamics and spatial genetic structure. Optimized for T. brasiliensis using field data pairwise fixation index (FST) from microsatellite loci, our simulations confirmed the importance of these three variables to understand vector genetic structure at the landscape level. We then ran prospective scenarios accounting for land-use change (deforestation and urbanization), which revealed that human-induced land-use change favored higher genetic diversity among sampling points. Conclusions/Significance Our work shows that mechanistic models may be useful tools to link observed patterns with processes involved in the population genetics of tropical pathogen vectors in heterogeneous social-ecological landscapes. Our hope is that our study may provide a testable and applicable modeling framework to a broad community of epidemiologists for formulating scenarios of landscape change consequences on vector dynamics, with potential implications for their surveillance and control. Worldwide, humans are modifying landscapes at an unprecedented rate. These modifications have an influence on the ecology of pathogen vectors, yet this issue has received relatively little input from modeling research. The current study presents guidelines for the use of a modeling framework for the representation of the dynamics and spatial genetic structure of pathogen vectors. It allows considering spatiotemporal landscape modifications explicitly, to represent human-altered modifications and consequences. We applied this modeling framework to Triatoma brasiliensis, vector of the pathogen Trypanosoma cruzi responsible for the Chagas disease, in the semi-arid Northeastern Brazil. Using field data of pairwise fixation index (FST) from microsatellite loci, we found that migration rate, maximum dispersal distance and attraction by domestic habitat were all key parameters to understand vector spatial genetic structure at the landscape level. At the interface across disciplines, this study provides to the community of epidemiologists a testable and applicable framework to foresee landscape modification consequences on vector dynamics and genetic structure, with potential implications for their surveillance and control.
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Affiliation(s)
- Francois Rebaudo
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
- * E-mail:
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz - Fiocruz, Rio de Janeiro, Rio de Janeiro, Brasil
| | - Carlos E. Almeida
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, UNESP, Araraquara, Sao Paolo, Brasil
| | - Jean-Francois Silvain
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
| | - Myriam Harry
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
| | - Olivier Dangles
- BEI-UR072, IRD, Gif-sur-Yvette, France
- LEGS-UPR9034, CNRS-UPSud11, Gif-sur-Yvette, France
- Instituto de Ecología, Campus Cotacota, Universidad Mayor San Andrés, La Paz, Bolivia
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Gabrie JA, Rueda MM, Canales M, Gyorkos TW, Sanchez AL. School hygiene and deworming are key protective factors for reduced transmission of soil-transmitted helminths among schoolchildren in Honduras. Parasit Vectors 2014; 7:354. [PMID: 25091035 PMCID: PMC4132920 DOI: 10.1186/1756-3305-7-354] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 07/29/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Among many neglected tropical diseases endemic in Honduras, soil-transmitted helminth (STH) infections are of particular importance. However, knowledge gaps remain in terms of risk factors involved in infection transmission. The aim of this study was to investigate risk factors associated with STH infections in schoolchildren living in rural Honduras. METHODS A cross-sectional study was conducted among Honduran rural schoolchildren in 2011. Demographic, socio-economic, and epidemiological data were obtained through a standardized questionnaire and STH infections were determined by the Kato-Katz method. Logistic regression models accounting for school clustering were used to assess putative risk factors for infection. RESULTS A total of 320 children completed the study. Prevalences for any STH and for Ascaris lumbricoides, Trichuris trichiura and hookworms were: 72.5%, 30.3%, 66.9% and 15.9%, respectively. A number of risk factors were identified at the individual, household, and school level. Boys were at increased odds of infection with hookworms (OR 2.33, 95% CI = 1.23-4.42). Higher socio-economic status in the family had a protective effect against infections by A. lumbricoides (OR 0.80, 95% CI = 0.65-0.99) and T. trichiura (OR 0.77, 95% CI = 0.63-0.94).Low school hygiene conditions significantly increased the odds for ascariasis (OR 14.85, 95% CI = 7.29-30.24), trichuriasis (OR 7.32, 95% CI = 3.71-14.45), mixed infections (OR 9.02, 95% CI = 4.66-17.46), and ascariasis intensity of infection (OR 3.32, 95% CI = 1.05 -10.52).Children attending schools not providing deworming treatment or that had provided it only once a year were at increased odds of ascariasis (OR 10.40, 95% CI = 4.39-24.65), hookworm (OR 2.92, 95% CI = 1.09-7.85) and mixed infections (OR 10.57, 95% CI = 4.53-24.66). CONCLUSIONS Poverty-reduction strategies will ultimately lead to sustainable control of STH infections in Honduras, but as shorter-term measures, uninterrupted bi-annual deworming treatment paired with improvements in school sanitary conditions may result in significant reductions of STH prevalence among Honduran schoolchildren.
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Affiliation(s)
| | | | | | | | - Ana Lourdes Sanchez
- Department of Health Sciences, Brock University, St, Catharines, Ontario, Canada.
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Abstract
Human gastrointestinal bacteria often share their environment with parasitic worms, allowing physical and physiological interaction between the two groups. Such associations have the potential to affect host health as well as the bacterial and helminth populations. Although still in its early stages, research on the interaction between the microbiome and parasitic helminths in humans offers the potential to improve health by manipulating the microbiome. Previously, supplementation with various nutritional compounds has been found to increase the abundance of potentially beneficial gut commensal bacteria. Thus, nutritional microbiome manipulation to produce an environment which may decrease malnutrition associated with helminth infection and/or aid host recovery from disease is conceivable. This review discusses the influence of the gut microbiota and helminths on host nutrition and immunity and the subsequent effects on the human host's overall health. It also discusses changes occurring in the microbiota upon helminth infections and the underlying mechanisms leading to these changes. There are still significant knowledge gaps which need to be filled before meaningful progress can be made in translating knowledge from studying the human gut microbiome into therapeutic strategies. Ultimately this review aims to discuss our current knowledge as well as highlight areas requiring further investigation.
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Williams AR, Fryganas C, Ramsay A, Mueller-Harvey I, Thamsborg SM. Direct anthelmintic effects of condensed tannins from diverse plant sources against Ascaris suum. PLoS One 2014; 9:e97053. [PMID: 24810761 PMCID: PMC4014605 DOI: 10.1371/journal.pone.0097053] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 04/01/2014] [Indexed: 11/20/2022] Open
Abstract
Ascaris suum is one of the most prevalent nematode parasites in pigs and causes significant economic losses, and also serves as a good model for A. lumbricoides, the large roundworm of humans that is ubiquitous in developing countries and causes malnutrition, stunted growth and compromises immunity to other pathogens. New treatment options for Ascaris infections are urgently needed, to reduce reliance on the limited number of synthetic anthelmintic drugs. In areas where Ascaris infections are common, ethno-pharmacological practices such as treatment with natural plant extracts are still widely employed. However, scientific validation of these practices and identification of the active compounds are lacking, although observed effects are often ascribed to plant secondary metabolites such as tannins. Here, we extracted, purified and characterised a wide range of condensed tannins from diverse plant sources and investigated anthelmintic effects against A. suum in vitro. We show that condensed tannins can have potent, direct anthelmintic effects against A. suum, as evidenced by reduced migratory ability of newly hatched third-stage larvae and reduced motility and survival of fourth-stage larvae recovered from pigs. Transmission electron microscopy showed that CT caused significant damage to the cuticle and digestive tissues of the larvae. Furthermore, we provide evidence that the strength of the anthelmintic effect is related to the polymer size of the tannin molecule. Moreover, the identity of the monomeric structural units of tannin polymers may also have an influence as gallocatechin and epigallocatechin monomers exerted significant anthelmintic activity whereas catechin and epicatechin monomers did not. Therefore, our results clearly document direct anthelmintic effects of condensed tannins against Ascaris and encourage further in vivo investigation to determine optimal strategies for the use of these plant compounds for the prevention and/or treatment of ascariosis.
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Affiliation(s)
- Andrew R. Williams
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
- * E-mail:
| | - Christos Fryganas
- Chemistry and Biochemistry Laboratory, School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | - Aina Ramsay
- Chemistry and Biochemistry Laboratory, School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | - Irene Mueller-Harvey
- Chemistry and Biochemistry Laboratory, School of Agriculture, Policy and Development, University of Reading, Reading, United Kingdom
| | - Stig M. Thamsborg
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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School-based health education targeting intestinal worms-further support for integrated control. PLoS Negl Trop Dis 2014; 8:e2621. [PMID: 24626109 PMCID: PMC3953022 DOI: 10.1371/journal.pntd.0002621] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Confalonieri UE, Margonari C, Quintão AF. Environmental change and the dynamics of parasitic diseases in the Amazon. Acta Trop 2014; 129:33-41. [PMID: 24056199 DOI: 10.1016/j.actatropica.2013.09.013] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 08/02/2013] [Accepted: 09/10/2013] [Indexed: 11/26/2022]
Abstract
The Amazonian environment is changing rapidly, due to deforestation, in the short term, and, climatic change is projected to alter its forest cover, in the next few decades. These modifications to the, environment have been altering the dynamics of infectious diseases which have natural foci in the, Amazonian biome, especially in its forest. Current land use practices which are changing the, epidemiological profile of the parasitic diseases in the region are road building; logging; mining; expansion of agriculture and cattle ranching and the building of large dams. Malaria and the cutaneous, leishmaniasis are the diseases best known for their rapid changes in response to environmental, modifications. Others such as soil-transmitted helminthiases, filarial infections and toxoplasmosis, which have part of their developmental cycles in the biophysical environment, are also expected to, change rapidly. An interdisciplinary approach and an integrated, international surveillance are needed, to manage the environmentally-driven changes in the Amazonian parasitic diseases in the near future.
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Abstract
Dung beetles are detrivorous insects that feed on and reproduce in the fecal material of vertebrates. This dependency on vertebrate feces implies frequent contact between dung beetles and parasitic helminths with a fecal component to their life-cycle. Interactions between dung beetles and helminths carry both positive and negative consequences for successful parasite transmission, however to date there has been no systematic review of dung beetle-helminth interactions, their epidemiological importance, or their underlying mechanisms. Here we review the observational evidence of beetle biodiversity-helminth transmission relationships, propose five mechanisms by which dung beetles influence helminth survival and transmission, and highlight areas for future research. Efforts to understand how anthropogenic impacts on biodiversity may influence parasite transmission must include the development of detailed, mechanistic understanding of the multiple interactions between free-living and parasitic species within ecological communities. The dung beetle-helminth system may be a promising future model system with which to understand these complex relationships.
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Bieri FA, Yuan LP, Li YS, He YK, Bedford A, Li RS, Guo FY, Li SM, Williams GM, McManus DP, Raso G, Gray DJ. Development of an educational cartoon to prevent worm infections in Chinese schoolchildren. Infect Dis Poverty 2013; 2:29. [PMID: 24289667 PMCID: PMC4177148 DOI: 10.1186/2049-9957-2-29] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/13/2013] [Indexed: 12/03/2022] Open
Abstract
Background With more than two billion people infected worldwide, soil-transmitted helminths (STH) are the most widespread infections. To date, STH control efforts rely predominantly on recurrent mass drug administration (MDA), which does not prevent reinfection. Additional public health measures including novel health educational tools are required for more sustained integrated control of STH. We describe the development of an educational cartoon video (The Magic Glasses) targeting STH infections in Chinese schoolchildren and its pilot testing in China. We applied an extensive community-based mixed methods approach involving input from the target group of 9–10 year old schoolchildren and key informants, such as teachers, doctors and parents, in order to identify potential STH infection risks in the study area and to formulate key messages for the cartoon. The development of the educational cartoon included three major steps: formative research, production, and pilot testing and revision. Results We found that most adults and approximately 50% of the schoolchildren were aware of roundworm (Ascaris) infection, but knowledge of transmission, prevention and treatment of STH was poor. Observations in the study area showed that unhygienic food practices, such as eating raw and unwashed fruit or playing in vegetable gardens previously fertilised with human faeces, posed major STH infection risks. Conclusions It was crucial to assess the intellectual, emotional, social and cultural background of the target population prior to video production in order to integrate the key messages of the cartoon into everyday situations. Overall, our strategy for the development of the cartoon and its incorporation into a health education package proved successful, and we provide a summary of recommendations for the development of future educational videos based on our experiences in China.
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Affiliation(s)
- Franziska A Bieri
- QIMR Berghofer Medical Research Institute, Herston, Brisbane, Queensland, Australia.
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Gómez A, Nichols E. Neglected wild life: Parasitic biodiversity as a conservation target. Int J Parasitol Parasites Wildl 2013; 2:222-7. [PMID: 24533340 PMCID: PMC3862516 DOI: 10.1016/j.ijppaw.2013.07.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 07/17/2013] [Accepted: 07/20/2013] [Indexed: 11/20/2022]
Abstract
Parasites appropriate host resources to feed and/or to reproduce, and lower host fitness to varying degrees. As a consequence, they can negatively impact human and animal health, food production, economic trade, and biodiversity conservation. They can also be difficult to study and have historically been regarded as having little influence on ecosystem organization and function. Not surprisingly, parasitic biodiversity has to date not been the focus of much positive attention from the conservation community. However, a growing body of evidence demonstrates that parasites are extremely diverse, have key roles in ecological and evolutionary processes, and that infection may paradoxically result in ecosystem services of direct human relevance. Here we argue that wildlife parasites should be considered meaningful conservation targets no less relevant than their hosts. We discuss their numerical and functional importance, current conservation status, and outline a series of non-trivial challenges to consider before incorporating parasite biodiversity in conservation strategies. We also suggest that addressing the key knowledge gaps and communication deficiencies that currently impede broad discussions about parasite conservation requires input from wildlife parasitologists.
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Affiliation(s)
- Andrés Gómez
- American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - Elizabeth Nichols
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
- Department of Ecology, Institute of Bioscience, University of São Paulo, 05508-900 São Paulo, SP, Brazil
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Verhagen LM, Incani RN, Franco CR, Ugarte A, Cadenas Y, Sierra Ruiz CI, Hermans PWM, Hoek D, Campos Ponce M, de Waard JH, Pinelli E. High malnutrition rate in Venezuelan Yanomami compared to Warao Amerindians and Creoles: significant associations with intestinal parasites and anemia. PLoS One 2013; 8:e77581. [PMID: 24143243 PMCID: PMC3797096 DOI: 10.1371/journal.pone.0077581] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 09/03/2013] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Children in rural areas experience the interrelated problems of poor growth, anemia and parasitic infections. We investigated the prevalence of and associations between intestinal helminth and protozoan infections, malnutrition and anemia in school-age Venezuelan children. METHODS This cross-sectional study was conducted in 390 children aged 4-16 years from three rural areas of Venezuela: the Amazon Region, Orinoco Delta and Carabobo State. Stool samples were collected for direct parasitic examinations. Anthropometric indicators of chronic (height-for-age Z score) and acute (weight-for-height and Body Mass Index (BMI)-for-age Z score in respectively children under 5 years of age and children aged 5 years and above) malnutrition were calculated. Multivariate linear and logistic regression models were built to determine factors associated with nutritional status and polyparasitism. RESULTS Hookworm and Strongyloides stercoralis prevalences were highest in children from the Amazon rainforest (respectively 72% and 18%) while children from the Orinoco Delta and Carabobo State showed higher rates of Ascaris lumbricoides (respectively 28% and 37%) and Trichuris trichiura (40% in both regions). The prevalence of Giardia lamblia infection was not significantly different between regions (average: 18%). Anemia prevalence was highest in the Amazon Region (24%). Hemoglobin levels were significantly decreased in children with a hookworm infection. Malnutrition was present in respectively 84%, 30% and 13% of children from the Amazon Region, Orinoco Delta and Carabobo State. In multivariate analysis including all regions, G. lamblia and helminth infections were significantly and negatively associated with respectively height-for-age and weight-for-height/BMI-for-age Z scores. Furthermore, hemoglobin levels were positively associated with the height-for-age Z score (0.11, 95% CI 0.02 - 0.20). CONCLUSIONS In rural populations in Venezuela helminthiasis and giardiasis were associated with acute and chronic nutritional status respectively. These data highlight the need for an integrated approach to control transmission of parasites and improve the health status of rural Venezuelan children.
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Affiliation(s)
- Lilly M. Verhagen
- Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela
- Laboratory of Pediatric Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Renzo N. Incani
- Departamento de Parasitología, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Venezuela
| | - Carolina R. Franco
- Departamento de Pediatría, Hospital de Niños ‘J.M. de los Ríos’, Caracas, Venezuela
| | - Alejandra Ugarte
- Escuela de Bioanálisis, Universidad Central de Venezuela, Caracas, Venezuela
| | - Yeneska Cadenas
- Escuela de Bioanálisis, Universidad Central de Venezuela, Caracas, Venezuela
| | - Carmen I. Sierra Ruiz
- Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela
| | - Peter W. M. Hermans
- Laboratory of Pediatric Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Denise Hoek
- Center for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Maiza Campos Ponce
- Department of Health Sciences, VU University, Amsterdam, The Netherlands
| | - Jacobus H. de Waard
- Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela
| | - Elena Pinelli
- Center for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
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Freeman MC, Ogden S, Jacobson J, Abbott D, Addiss DG, Amnie AG, Beckwith C, Cairncross S, Callejas R, Colford JM, Emerson PM, Fenwick A, Fishman R, Gallo K, Grimes J, Karapetyan G, Keene B, Lammie PJ, MacArthur C, Lochery P, Petach H, Platt J, Prabasi S, Rosenboom JW, Roy S, Saywell D, Schechtman L, Tantri A, Velleman Y, Utzinger J. Integration of water, sanitation, and hygiene for the prevention and control of neglected tropical diseases: a rationale for inter-sectoral collaboration. PLoS Negl Trop Dis 2013; 7:e2439. [PMID: 24086781 PMCID: PMC3784463 DOI: 10.1371/journal.pntd.0002439] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Improvements of water, sanitation, and hygiene (WASH) infrastructure and appropriate health-seeking behavior are necessary for achieving sustained control, elimination, or eradication of many neglected tropical diseases (NTDs). Indeed, the global strategies to fight NTDs include provision of WASH, but few programs have specific WASH targets and approaches. Collaboration between disease control programs and stakeholders in WASH is a critical next step. A group of stakeholders from the NTD control, child health, and WASH sectors convened in late 2012 to discuss opportunities for, and barriers to, collaboration. The group agreed on a common vision, namely "Disease-free communities that have adequate and equitable access to water and sanitation, and that practice good hygiene." Four key areas of collaboration were identified, including (i) advocacy, policy, and communication; (ii) capacity building and training; (iii) mapping, data collection, and monitoring; and (iv) research. We discuss strategic opportunities and ways forward for enhanced collaboration between the WASH and the NTD sectors.
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Affiliation(s)
- Matthew C. Freeman
- Department of Environmental Health, Emory University, Atlanta, Georgia, United States of America
| | - Stephanie Ogden
- Department of Environmental Health, Emory University, Atlanta, Georgia, United States of America
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
- International Trachoma Initiative, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Julie Jacobson
- Bill & Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Daniel Abbott
- Save the Children, Washington, D.C., United States of America
| | - David G. Addiss
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Asrat G. Amnie
- Hubert Department of Global Health, Emory University, Atlanta, Georgia, United States of America
| | - Colin Beckwith
- International Trachoma Initiative, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Sandy Cairncross
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Rafael Callejas
- Millennium Water Alliance, Washington, D.C., United States of America
| | - Jack M. Colford
- Department of Epidemiology, University of California-Berkeley, Berkeley, California, United States of America
| | - Paul M. Emerson
- The Carter Center, Atlanta, Georgia, United States of America
| | - Alan Fenwick
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
| | | | - Kerry Gallo
- Children Without Worms, Taskforce for Global Health, Atlanta, Georgia, United States of America
| | - Jack Grimes
- Schistosomiasis Control Initiative, Imperial College, London, United Kingdom
- Department of Civil and Environmental Engineering, Imperial College, London, United Kingdom
| | | | - Brooks Keene
- CARE International, Atlanta, Georgia, United States of America
| | - Patrick J. Lammie
- Taskforce for Global Health, Atlanta, Georgia, United States of America
- Center for Global Health, United States Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Chad MacArthur
- Helen Keller International, New York, New York, United States of America
| | - Peter Lochery
- CARE International, Atlanta, Georgia, United States of America
| | - Helen Petach
- United States Agency for International Development, Washington, D.C., United States of America
| | - Jennifer Platt
- WASH Advocates, Washington, D.C., United States of America
| | - Sarina Prabasi
- ORBIS International, New York, New York, United States of America
| | | | - Sharon Roy
- Waterborne Disease Prevention Branch, United States Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Darren Saywell
- Plan International, Washington, D.C., United States of America
| | - Lisa Schechtman
- WaterAid America, Washington, D.C., United States of America
| | - Anupama Tantri
- Sabin Vaccine Institute, Washington, D.C., United States of America
| | | | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Qian MB, Chen YD, Fang YY, Tan T, Zhu TJ, Zhou CH, Wang GF, Xu LQ, Zhou XN. Epidemiological profile of Clonorchis sinensis infection in one community, Guangdong, People's Republic of China. Parasit Vectors 2013; 6:194. [PMID: 23816055 PMCID: PMC3750548 DOI: 10.1186/1756-3305-6-194] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Accepted: 06/29/2013] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Clonorchiasis caused by ingesting improperly prepared fish ranks among the most important but still neglected food-borne parasitic diseases, especially in the People's Republic of China (P.R. China). To promote the implementation of interventions efficiently, the demonstration of an epidemiological profile of Clonorchis sinensis infection is essential in hyper-epidemic areas. METHODS In one community with higher levels of economic development in Guangdong province, P.R. China, villagers were motivated to provide stool samples for examining helminth eggs. Then, those infected with C. sinensis completed the structured questionnaire including demographical characteristics, knowledge and behavior. RESULTS A total of 293 villagers infected with C. sinensis participated in questionnaire investigation. Among them, 94.54% were adult and 93.17% were indigenous. The geometric mean of C. sinensis eggs per gram of feces in the children, adult females and adult males was 58, 291 and 443, respectively. The divergence between knowledge and behavior in the adults, especially the adult males, was shown. Out of 228 persons eating raw fish, 160 did it more frequently at restaurants, the proportion of which varied in different populations, showing 25.00%, 54.88% and 80.28% in the children, adult females and adult males, respectively. CONCLUSIONS Different interventions need to be adopted in different populations. Chemotherapy should be prioritized in the adults, especially the adult males. In addition, health education targeting the children, is essential and may play a crucial role in controlling clonorchiasis in the long term. In order to successfully control clonorchiasis, intervention in the restaurant should not be overlooked in some endemic areas.
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Affiliation(s)
- Men-Bao Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Ying-Dan Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Yue-Yi Fang
- Center for Disease Control and Prevention of Guangdong Province, Guangzhou, People’s Republic of China
| | - Tan Tan
- Center for Disease Control and Prevention of Shunde District, Shunde, People’s Republic of China
| | - Ting-Jun Zhu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Chang-Hai Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Guo-Fei Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Long-Qi Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
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Abstract
HIV research has identified approaches that can be combined to be more effective in transmission reduction than any 1 modality alone: delayed adolescent sexual debut, mutual monogamy or sexual partner reduction, correct and consistent condom use, pre-exposure prophylaxis with oral antiretroviral drugs or vaginal microbicides, voluntary medical male circumcision, antiretroviral therapy (ART) for prevention (including prevention of mother to child HIV transmission [PMTCT]), treatment of sexually transmitted infections, use of clean needles for all injections, blood screening prior to donation, a future HIV prime/boost vaccine, and the female condom. The extent to which evidence-based modalities can be combined to prevent substantial HIV transmission is largely unknown, but combination approaches that are truly implementable in field conditions are likely to be far more effective than single interventions alone. Analogous to PMTCT, "treatment as prevention" for adult-to-adult transmission reduction includes expanded HIV testing, linkage to care, antiretroviral coverage, retention in care, adherence to therapy, and management of key co-morbidities such as depression and substance use. With successful viral suppression, persons with HIV are far less infectious to others, as we see in the fields of sexually transmitted infection control and mycobacterial disease control (tuberculosis and leprosy). Combination approaches are complex, may involve high program costs, and require substantial global commitments. We present a rationale for such investments and cite an ongoing research agenda that seeks to determine how feasible and cost-effective a combination prevention approach would be in a variety of epidemic contexts, notably that in a sub-Saharan Africa.
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Affiliation(s)
- Sten H Vermund
- Vanderbilt Institute for Global Health and Department of Pediatrics, Vanderbilt School of Medicine, Nashville, TN 37203, USA.
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65
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Human neurocysticercosis: immunological features involved in the host's susceptibility to become infected and to develop disease. Microbes Infect 2013; 15:524-30. [PMID: 23542217 DOI: 10.1016/j.micinf.2013.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 03/13/2013] [Accepted: 03/15/2013] [Indexed: 11/23/2022]
Abstract
Human neurocysticercosis (NC) is a clinically and radiologically heterogeneous disease caused by the establishment of Taenia solium larvae in the central nervous system. Herein, the immunological and endocrinological features involved in resistance to infection and severe forms of the disease are reviewed, and their clinical relevance is discussed.
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66
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Qian MB, Chen YD, Yan F. Time to tackle clonorchiasis in China. Infect Dis Poverty 2013; 2:4. [PMID: 23849773 PMCID: PMC3707093 DOI: 10.1186/2049-9957-2-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 01/31/2013] [Indexed: 01/19/2023] Open
Abstract
Recent publication of the global epidemiology of clonorchiasis and its relationship with cholangiocarcinoma in the journal of Infectious Diseases of Poverty has stressed the importance of Clonorchis sinensis infection. To further demonstrate its threat on public health, especially in China, comparisons between clonorchiasis and hepatitis B are made in terms of epidemiology, clinical symptoms and carcinogenicity, disability, as well as changing trends. Furthermore, major problems and prioritized researches are argued, from basic biology to intervention. Imbalance between the majority of infected population and the minority of researches in China urges for more work from Chinese scientists and international cooperation.
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Affiliation(s)
- Men-Bao Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Ying-Dan Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborative Center for Malaria, Schistosomiasis and Filariasis; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, People’s Republic of China
| | - Fei Yan
- School of Public Health, Fudan University, Shanghai, People’s Republic of China
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68
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The promise and pitfalls of mass drug administration to control intestinal helminth infections. Curr Opin Infect Dis 2012; 25:584-9. [DOI: 10.1097/qco.0b013e328357e4cf] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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69
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Boatin BA, Basáñez MG, Prichard RK, Awadzi K, Barakat RM, García HH, Gazzinelli A, Grant WN, McCarthy JS, N'Goran EK, Osei-Atweneboana MY, Sripa B, Yang GJ, Lustigman S. A research agenda for helminth diseases of humans: towards control and elimination. PLoS Negl Trop Dis 2012; 6:e1547. [PMID: 22545161 PMCID: PMC3335858 DOI: 10.1371/journal.pntd.0001547] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human helminthiases are of considerable public health importance in sub-Saharan Africa, Asia, and Latin America. The acknowledgement of the disease burden due to helminth infections, the availability of donated or affordable drugs that are mostly safe and moderately efficacious, and the implementation of viable mass drug administration (MDA) interventions have prompted the establishment of various large-scale control and elimination programmes. These programmes have benefited from improved epidemiological mapping of the infections, better understanding of the scope and limitations of currently available diagnostics and of the relationship between infection and morbidity, feasibility of community-directed or school-based interventions, and advances in the design of monitoring and evaluation (M&E) protocols. Considerable success has been achieved in reducing morbidity or suppressing transmission in a number of settings, whilst challenges remain in many others. Some of the obstacles include the lack of diagnostic tools appropriate to the changing requirements of ongoing interventions and elimination settings; the reliance on a handful of drugs about which not enough is known regarding modes of action, modes of resistance, and optimal dosage singly or in combination; the difficulties in sustaining adequate coverage and compliance in prolonged and/or integrated programmes; an incomplete understanding of the social, behavioural, and environmental determinants of infection; and last, but not least, very little investment in research and development (R&D). The Disease Reference Group on Helminth Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), was given the mandate to undertake a comprehensive review of recent advances in helminthiases research, identify research gaps, and rank priorities for an R&D agenda for the control and elimination of these infections. This review presents the processes undertaken to identify and rank ten top research priorities; discusses the implications of realising these priorities in terms of their potential for improving global health and achieving the Millennium Development Goals (MDGs); outlines salient research funding needs; and introduces the series of reviews that follow in this PLoS Neglected Tropical Diseases collection, "A Research Agenda for Helminth Diseases of Humans."
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Affiliation(s)
- Boakye A. Boatin
- Lymphatic Filariasis Support Centre, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
- Institute of Parasitology, McGill University, Montreal, Canada
| | - María-Gloria Basáñez
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom
| | | | - Kwablah Awadzi
- Onchocerciasis Chemotherapy Research Centre, Hohoe Hospital, Hohoe, Ghana
| | - Rashida M. Barakat
- High Institute of Public Health, Alexandria University, Alexandria, Egypt
| | - Héctor H. García
- Department of Microbiology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Andrea Gazzinelli
- Department of Maternal and Child Nursing and Public Health, School of Nursing, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Warwick N. Grant
- The Nematode Functional Genomics Laboratory, La Trobe University, Victoria, Australia
| | - James S. McCarthy
- Queensland Institute of Medical Research, University of Queensland, Herston, Australia
| | - Eliézer K. N'Goran
- Laboratoire de Zoologie et de Biologie Animale, Université de Cocody, UFR Biosciences, Abidjan, Côte d'Ivoire
| | - Mike Y. Osei-Atweneboana
- Council for Scientific and Industrial Research (CSIR), Department of Environmental Biology and Health, Water Research Institute, Accra, Ghana
| | - Banchob Sripa
- Tropical Disease Research Laboratory, Division of Experimental Pathology, Department of Pathology, Khon Kaen University, Khon Kaen, Thailand
| | - Guo-Jing Yang
- Department of Schistosomiasis Control, Jiangsu Institute of Parasitic Diseases, Meiyuan Yangxiang, Wuxi, People's Republic of China
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
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Affiliation(s)
- Jürg Utzinger
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Osei-Atweneboana MY, Lustigman S, Prichard RK, Boatin BA, Basáñez MG. A research agenda for helminth diseases of humans: health research and capacity building in disease-endemic countries for helminthiases control. PLoS Negl Trop Dis 2012; 6:e1602. [PMID: 22545167 PMCID: PMC3335878 DOI: 10.1371/journal.pntd.0001602] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Capacity building in health research generally, and helminthiasis research particularly, is pivotal to the implementation of the research and development agenda for the control and elimination of human helminthiases that has been proposed thematically in the preceding reviews of this collection. Since helminth infections affect human populations particularly in marginalised and low-income regions of the world, they belong to the group of poverty-related infectious diseases, and their alleviation through research, policy, and practice is a sine qua non condition for the achievement of the United Nations Millennium Development Goals. Current efforts supporting research capacity building specifically for the control of helminthiases have been devised and funded, almost in their entirety, by international donor agencies, major funding bodies, and academic institutions from the developed world, contributing to the creation of (not always equitable) North-South "partnerships". There is an urgent need to shift this paradigm in disease-endemic countries (DECs) by refocusing political will, and harnessing unshakeable commitment by the countries' governments, towards health research and capacity building policies to ensure long-term investment in combating and sustaining the control and eventual elimination of infectious diseases of poverty. The Disease Reference Group on Helminth Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), was given the mandate to review helminthiases research and identify research priorities and gaps. This paper discusses the challenges confronting capacity building for parasitic disease research in DECs, describes current capacity building strategies with particular reference to neglected tropical diseases and human helminthiases, and outlines recommendations to redress the balance of alliances and partnerships for health research between the developed countries of the "North" and the developing countries of the "South". We argue that investing in South-South collaborative research policies and capacity is as important as their North-South counterparts and is essential for scaled-up and improved control of helminthic diseases and ultimately for regional elimination.
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Affiliation(s)
- Mike Y. Osei-Atweneboana
- Council for Scientific and Industrial Research, Water Research Institute, Department of Environmental Biology and Health, Accra, Ghana
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | | | - Boakye A. Boatin
- Institute of Parasitology, McGill University, Montreal, Canada
- Lymphatic Filariasis Support Centre, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
| | - María-Gloria Basáñez
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine (St Mary's campus), Imperial College London, London, United Kingdom
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Prichard RK, Basáñez MG, Boatin BA, McCarthy JS, García HH, Yang GJ, Sripa B, Lustigman S. A research agenda for helminth diseases of humans: intervention for control and elimination. PLoS Negl Trop Dis 2012; 6:e1549. [PMID: 22545163 PMCID: PMC3335868 DOI: 10.1371/journal.pntd.0001549] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recognising the burden helminth infections impose on human populations, and particularly the poor, major intervention programmes have been launched to control onchocerciasis, lymphatic filariasis, soil-transmitted helminthiases, schistosomiasis, and cysticercosis. The Disease Reference Group on Helminth Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), was given the mandate to review helminthiases research and identify research priorities and gaps. A summary of current helminth control initiatives is presented and available tools are described. Most of these programmes are highly dependent on mass drug administration (MDA) of anthelmintic drugs (donated or available at low cost) and require annual or biannual treatment of large numbers of at-risk populations, over prolonged periods of time. The continuation of prolonged MDA with a limited number of anthelmintics greatly increases the probability that drug resistance will develop, which would raise serious problems for continuation of control and the achievement of elimination. Most initiatives have focussed on a single type of helminth infection, but recognition of co-endemicity and polyparasitism is leading to more integration of control. An understanding of the implications of control integration for implementation, treatment coverage, combination of pharmaceuticals, and monitoring is needed. To achieve the goals of morbidity reduction or elimination of infection, novel tools need to be developed, including more efficacious drugs, vaccines, and/or antivectorial agents, new diagnostics for infection and assessment of drug efficacy, and markers for possible anthelmintic resistance. In addition, there is a need for the development of new formulations of some existing anthelmintics (e.g., paediatric formulations). To achieve ultimate elimination of helminth parasites, treatments for the above mentioned helminthiases, and for taeniasis and food-borne trematodiases, will need to be integrated with monitoring, education, sanitation, access to health services, and where appropriate, vector control or reduction of the parasite reservoir in alternative hosts. Based on an analysis of current knowledge gaps and identification of priorities, a research and development agenda for intervention tools considered necessary for control and elimination of human helminthiases is presented, and the challenges to be confronted are discussed.
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