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Castillo G, Fustamante L, Delgado-Kamiche AD, Camen-Orozco RP, Clark T, Bernal E, Morales-Alvarez J, Ferrufino M, Mamani-Palomino J, Bustos JA, Garcia HH, Gavidia CM, Gilman RH, Verastegui M. Understanding the pathogenic mechanisms and therapeutic effects in neurocysticercosis. Brain Pathol 2024; 34:e13237. [PMID: 38212958 PMCID: PMC11328352 DOI: 10.1111/bpa.13237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 01/01/2024] [Indexed: 01/13/2024] Open
Abstract
Despite being a leading cause of acquired seizures in endemic regions, the pathological mechanisms of neurocysticercosis are still poorly understood. This study aims to investigate the impact of anthelmintic treatment on neuropathological features in a rat model of neurocysticercosis. Rats were intracranially infected with Taenia solium oncospheres and treated with albendazole + praziquantel (ABZ), oxfendazole + praziquantel (OXF), or untreated placebo (UT) for 7 days. Following the last dose of treatment, brain tissues were evaluated at 24 h and 2 months. We performed neuropathological assessment for cyst damage, perilesional brain inflammation, presence of axonal spheroids, and spongy changes. Both treatments showed comparable efficacy in cyst damage and inflammation. The presence of spongy change correlated with spheroids counts and were not affected by anthelmintic treatment. Compared to white matter, gray matter showed greater spongy change (91.7% vs. 21.4%, p < 0.0001), higher spheroids count (45.2 vs. 0.2, p = 0.0001), and increased inflammation (72.0% vs. 21.4%, p = 0.003). In this rat model, anthelmintic treatment destroyed brain parasitic cysts at the cost of local inflammation similar to what is described in human neurocysticercosis. Axonal spheroids and spongy changes as markers of damage were topographically correlated, and not affected by anthelmintic treatment.
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Affiliation(s)
- Gino Castillo
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Lizbeth Fustamante
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Ana D Delgado-Kamiche
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Rogger P Camen-Orozco
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Taryn Clark
- The Department of International Health, Bloomberg School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Emergency Medicine, SUNY Downstate Medical Center, Kings County Hospital Medical Center, Brooklyn, New York, New York, United States
| | - Edson Bernal
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Jemima Morales-Alvarez
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Maria Ferrufino
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Javier Mamani-Palomino
- Facultad de Medicina Veterinaria y Salud animal, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Javier A Bustos
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Hector H Garcia
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - Cesar M Gavidia
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Robert H Gilman
- The Department of International Health, Bloomberg School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Manuela Verastegui
- Infectious Diseases Laboratory Research-LID, Facultad de Ciencia e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
- Asociación Benéfica Prisma, Lima, Peru
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2
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Araújo JAA, Gomes TC, Lima VCN, Silva YBD, Lino Junior RDS, Vinaud MC. Oxfendazole Nitazoxanide combination in experimental neurocysticercosis - Anti-inflammatory and cysticidal effects. Exp Parasitol 2024; 262:108764. [PMID: 38677580 DOI: 10.1016/j.exppara.2024.108764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 04/29/2024]
Abstract
Neurocysticercosis (NCC) is a parasitic infection caused by the larval stage of the pork tapeworm, Taenia solium. The complications of NCC include seizures, headaches, cognitive impairment, and focal neurological deficits. In addition to antiparasitic drugs and surgery, the management of NCC includes the use of corticosteroids to reduce inflammation and control symptoms. The traditional treatment with albendazole and praziquantel has not been altered over 30 years and present several side effects. There are other anti-helminthic drugs such as oxfendazole and nitazoxanide that may show efficacy in NCC treatment. The aim of this study was to determine the histopathologic aspects of experimental NCC after in vivo treatment with the combination of oxfendazole and nitazoxanide. Balb/c mice were infected with T. crassiceps cysticerci and divided into groups of 10 animals each that received a single dose through gavage as follows: group treated with NaCl 0.9% (control group); group treated by monotherapy of the anti-helminthic drugs, 30 mg/kg in single dose of oxfendazole (OXF) or nitazoxanide (NTZ); and groups treated with the combination of the drugs (OXF/NTZ group). Macroscopic and microscopic analysis were performed. There was greater presence of final stage cysticerci after treatment. The microscopic analysis of the general pathological processes showed that the monotherapy with all treatment groups induced higher perivasculitis than what was observed in the control group. In contrast, the combination treatment showed a lower observation of PMN and MN inflammatory infiltration in comparison to the other treatments and to the control one. These results show that indeed the association of benzimidazole derivatives which present both anti-helminthic and anti-inflammatory properties with other cysticidal drugs are beneficial for the NCC treatment in which the aim is to destroy parasite without inducing inflammatory damage in the brain tissue.
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Affiliation(s)
- Jefferson Aber Alves Araújo
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil
| | - Taynara Cristina Gomes
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil
| | - Vanessa Cindy Neres Lima
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil
| | - Yngrid Batista da Silva
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil
| | - Ruy de Souza Lino Junior
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil
| | - Marina Clare Vinaud
- Tropical Pathology and Public Health Institute, Federal University of Goias, Goiânia, Goiás, CEP: 74605-050, Brazil.
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3
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Prodjinotho UF, Gres V, Henkel F, Lacorcia M, Dandl R, Haslbeck M, Schmidt V, Winkler AS, Sikasunge C, Jakobsson PJ, Henneke P, Esser-von Bieren J, Prazeres da Costa C. Helminthic dehydrogenase drives PGE 2 and IL-10 production in monocytes to potentiate Treg induction. EMBO Rep 2022; 23:e54096. [PMID: 35357743 PMCID: PMC9066053 DOI: 10.15252/embr.202154096] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/02/2022] [Accepted: 03/14/2022] [Indexed: 01/03/2023] Open
Abstract
Immunoregulation of inflammatory, infection‐triggered processes in the brain constitutes a central mechanism to control devastating disease manifestations such as epilepsy. Observational studies implicate the viability of Taenia solium cysts as key factor determining severity of neurocysticercosis (NCC), the most common cause of epilepsy, especially in children, in Sub‐Saharan Africa. Viable, in contrast to decaying, cysts mostly remain clinically silent by yet unknown mechanisms, potentially involving Tregs in controlling inflammation. Here, we show that glutamate dehydrogenase from viable cysts instructs tolerogenic monocytes to release IL‐10 and the lipid mediator PGE2. These act in concert, converting naive CD4+ T cells into CD127−CD25hiFoxP3+CTLA‐4+ Tregs, through the G protein‐coupled receptors EP2 and EP4 and the IL‐10 receptor. Moreover, while viable cyst products strongly upregulate IL‐10 and PGE2 transcription in microglia, intravesicular fluid, released during cyst decay, induces pro‐inflammatory microglia and TGF‐β as potential drivers of epilepsy. Inhibition of PGE2 synthesis and IL‐10 signaling prevents Treg induction by viable cyst products. Harnessing the PGE2‐IL‐10 axis and targeting TGF‐ß signaling may offer an important therapeutic strategy in inflammatory epilepsy and NCC.
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Affiliation(s)
- Ulrich Fabien Prodjinotho
- Institute for Medical Microbiology, Immunology and Hygiene, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany.,Center for Global Health, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | - Vitka Gres
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Fiona Henkel
- Center of Allergy and Environment (ZAUM), Technical University of Munich and Helmholtz Center Munich, Munich, Germany
| | - Matthew Lacorcia
- Institute for Medical Microbiology, Immunology and Hygiene, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany
| | - Ramona Dandl
- Department of Chemistry, Technical University Munich (TUM), Garching, Germany
| | - Martin Haslbeck
- Department of Chemistry, Technical University Munich (TUM), Garching, Germany
| | - Veronika Schmidt
- Center for Global Health, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany.,Department of Neurology, University Hospital, Klinikum rechts der Isar, Technical University Munich (TUM), Munich, Germany.,Center for Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Andrea Sylvia Winkler
- Center for Global Health, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany.,Department of Neurology, University Hospital, Klinikum rechts der Isar, Technical University Munich (TUM), Munich, Germany.,Center for Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Chummy Sikasunge
- Department of Paraclinicals, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Per-Johan Jakobsson
- Rheumatology Unit, Department of Medicine, Solna, Karolinska University Hospital, Stockholm, Sweden
| | - Philipp Henneke
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center and Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Center for Pediatrics and Adolescent Medicine, Medical Center, University of Freiburg, Freiburg, Germany.,Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Julia Esser-von Bieren
- Center of Allergy and Environment (ZAUM), Technical University of Munich and Helmholtz Center Munich, Munich, Germany
| | - Clarissa Prazeres da Costa
- Institute for Medical Microbiology, Immunology and Hygiene, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany.,Center for Global Health, TUM School of Medicine, Technical University of Munich (TUM), Munich, Germany.,German Center for Infection and Research (DZIF), Munich, Germany
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4
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Validating efficacy of Sericocomopsis hildebrandtii, Carissa edulis, and Ximenia americana in treating Taenia solium cysticercosis in pigs: A randomized controlled trial. EXPERIMENTAL RESULTS 2021. [DOI: 10.1017/exp.2021.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Abstract
Ethnoveterinary use of plants dates back to ancient times. This study aimed to validate purported efficacy of Sericocomopsis hildebrandtii and a concoction of Carissa edulis and Ximenia americana in treating Taenia solium cysticercosis in pigs. Twenty-four infected pigs were randomly allocated to T1, T2, and T0 groups, each with eight pigs. Each T1 pig was provided with 8 g of S. hildebrandtii root powder, whereas each T2 pig was given 8 g of the concoction. T0 was a control. The pigs were slaughtered 16 weeks post treatment and carcase dissections were performed to establish cyst numbers. T1 cyst numbers were significantly lower than those of T0 (p = .004) and T2 (p = .013). No difference was observed between T2 and T0. This study validated efficacy of S. hildebrandtii but not of X. americana and C. edulis. Further studies are necessary for validation and documentation of plants of ethnoveterinary importance.
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5
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Lightowlers MW, Gasser RB, Hemphill A, Romig T, Tamarozzi F, Deplazes P, Torgerson PR, Garcia HH, Kern P. Advances in the treatment, diagnosis, control and scientific understanding of taeniid cestode parasite infections over the past 50 years. Int J Parasitol 2021; 51:1167-1192. [PMID: 34757089 DOI: 10.1016/j.ijpara.2021.10.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 02/07/2023]
Abstract
In the past 50 years, enormous progress has been made in the diagnosis, treatment and control of taeniid cestode infections/diseases and in the scientific understanding thereof. Most interest in this group of parasites stems from the serious diseases that they cause in humans. It is through this lens that we summarize here the most important breakthroughs that have made a difference to the treatment of human diseases caused by these parasites, reduction in transmission of the taeniid species associated with human disease, or understanding of the parasites' biology likely to impact diagnosis or treatment in the foreseeable future. Key topics discussed are the introduction of anti-cestode drugs, including benzimidazoles and praziquantel, and the development of new imaging modalities that have transformed the diagnosis and post-treatment monitoring of human echinococcoses and neurocysticercosis. The availability of new anti-cestode drugs for use in dogs and a detailed understanding of the transmission dynamics of Echinococcus granulosus sensu lato have underpinned successful programs that have eliminated cystic echinococcosis in some areas of the world and greatly reduced the incidence of infection in others. Despite these successes, cystic and alveolar echinococcosis and neurocysticercosis continue to be prevalent in many parts of the world, requiring new or renewed efforts to prevent the associated taeniid infections. Major advances made in the development of practical vaccines against E. granulosus and Taenia solium will hopefully assist in this endeavour, as might the understanding of the parasites' biology that have come from an elucidation of the nuclear genomes of each of the most important taeniid species causing human diseases.
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Affiliation(s)
- Marshall W Lightowlers
- Department of Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, 250 Princes Highway, Werribee, Victoria 3030, Australia.
| | - Robin B Gasser
- Department of Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Andrew Hemphill
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Thomas Romig
- University of Hohenheim, Parasitology Unit, Emil-Wolff-Strasse 34, 70599 Stuttgart, Germany
| | - Francesca Tamarozzi
- Department of Infectious Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, 37024 Negrar di Valpolicella, Verona, Italy
| | - Peter Deplazes
- Institute of Parasitology, Vetsuisse, and Medical Faculty, University of Zürich, Zürich, Switzerland
| | - Paul R Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland
| | - Hector H Garcia
- Infectious Diseases Laboratory Research-LID, Faculty of Science and Philosophy, Alberto Cazorla Talleri, Universidad Peruana Cayetano Heredia, Lima, Perú; Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Perú
| | - Peter Kern
- Ulm University Hospital, Division of Infectious Diseases, Albert-Einstein-Allee 23, 89081 Ulm, Germany
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Pray IW, Pizzitutti F, Bonnet G, Gonzales-Gustavson E, Wakeland W, Pan WK, Lambert WE, Gonzalez AE, Garcia HH, O’Neal SE. Validation of a spatial agent-based model for Taenia solium transmission ("CystiAgent") against a large prospective trial of control strategies in northern Peru. PLoS Negl Trop Dis 2021; 15:e0009885. [PMID: 34705827 PMCID: PMC8575314 DOI: 10.1371/journal.pntd.0009885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 11/08/2021] [Accepted: 10/08/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The pork tapeworm (Taenia solium) is a parasitic helminth that imposes a major health and economic burden on poor rural populations around the world. As recognized by the World Health Organization, a key barrier for achieving control of T. solium is the lack of an accurate and validated simulation model with which to study transmission and evaluate available control and elimination strategies. CystiAgent is a spatially-explicit agent based model for T. solium that is unique among T. solium models in its ability to represent key spatial and environmental features of transmission and simulate spatially targeted interventions, such as ring strategy. METHODS/PRINCIPAL FINDINGS We validated CystiAgent against results from the Ring Strategy Trial (RST)-a large cluster-randomized trial conducted in northern Peru that evaluated six unique interventions for T. solium control in 23 villages. For the validation, each intervention strategy was replicated in CystiAgent, and the simulated prevalences of human taeniasis, porcine cysticercosis, and porcine seroincidence were compared against prevalence estimates from the trial. Results showed that CystiAgent produced declines in transmission in response to each of the six intervention strategies, but overestimated the effect of interventions in the majority of villages; simulated prevalences for human taenasis and porcine cysticercosis at the end of the trial were a median of 0.53 and 5.0 percentages points less than prevalence observed at the end of the trial, respectively. CONCLUSIONS/SIGNIFICANCE The validation of CystiAgent represented an important step towards developing an accurate and reliable T. solium transmission model that can be deployed to fill critical gaps in our understanding of T. solium transmission and control. To improve model accuracy, future versions would benefit from improved data on pig immunity and resistance, field effectiveness of anti-helminthic treatment, and factors driving spatial clustering of T. solium infections including dispersion and contact with T. solium eggs in the environment.
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Affiliation(s)
- Ian W. Pray
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, Oregon, United States of America
| | - Francesco Pizzitutti
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, Oregon, United States of America
| | - Gabrielle Bonnet
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, Oregon, United States of America
| | - Eloy Gonzales-Gustavson
- Tropical and Highlands Veterinary Research Institute, School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, EL Mantaro, Peru
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Wayne Wakeland
- Systems Science Program, Portland State University, Portland, Oregon, United States of America
| | - William K. Pan
- Duke Global Health Institute & Nicholas School of Environment, Duke University, Durham, North Carolina, United States of America
| | - William E. Lambert
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, Oregon, United States of America
| | - Armando E. Gonzalez
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Hector H. Garcia
- School of Sciences, Department of Microbiology, Universidad Peruana Cayetano Heredia, Lima, Peru
- Center for Global Health Tumbes, Universidad Peruana Cayetano Heredia, Tumbes, Peru
| | - Seth E. O’Neal
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, Oregon, United States of America
- Center for Global Health Tumbes, Universidad Peruana Cayetano Heredia, Tumbes, Peru
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7
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Dixon MA, Winskill P, Harrison WE, Basáñez MG. Taenia solium taeniasis/cysticercosis: From parasite biology and immunology to diagnosis and control. ADVANCES IN PARASITOLOGY 2021; 112:133-217. [PMID: 34024358 DOI: 10.1016/bs.apar.2021.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Infection with the pork tapeworm (Taenia solium) is responsible for a substantial global burden of disease, not only restricted to its impact on human health, but also resulting in a considerable economic burden to smallholder pig farmers due to pig cysticercosis infection. The life-cycle, parasitology and immunology of T. solium are complex, involving pigs (the intermediate host, harbouring the larval metacestode stage), humans (the definitive host, harbouring the adult tapeworm, in addition to acting as accidental intermediate hosts) and the environment (the source of infection with eggs/proglottids). We review the parasitology, immunology, and epidemiology of the infection associated with each of the T. solium life-cycle stages, including the pre-adult/adult tapeworm responsible for human taeniasis; post-oncosphere and cysticercus associated with porcine and human cysticercosis, and the biological characteristics of eggs in the environment. We discuss the burden associated, in endemic settings, with neurocysticercosis (NCC) in humans, and the broader cross-sectoral economic impact associated both with NCC and porcine cysticercosis, the latter impacting food-value chains. Existing tools for diagnostics and control interventions that target different stages of the T. solium transmission cycle are reviewed and their limitations discussed. Currently, no national T. solium control programmes have been established in endemic areas, with further work required to identify optimal strategies according to epidemiological setting. There is increasing evidence suggesting that cross-sectoral interventions which target the parasite in both the human and pig host provide the most effective approaches for achieving control and ultimately elimination. We discuss future avenues for research on T. solium to support the attainment of the goals proposed in the revised World Health Organisation neglected tropical diseases roadmap for 2021-2030 adopted at the 73rd World Health Assembly in November 2020.
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Affiliation(s)
- Matthew A Dixon
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom; MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom; Schistosomiasis Control Initiative Foundation (SCI Foundation), London, United Kingdom
| | - Peter Winskill
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
| | - Wendy E Harrison
- Schistosomiasis Control Initiative Foundation (SCI Foundation), London, United Kingdom
| | - Maria-Gloria Basáñez
- London Centre for Neglected Tropical Disease Research (LCNTDR), Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom; MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.
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8
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Kabululu ML, Johansen MV, Mlangwa JED, Mkupasi EM, Braae UC, Trevisan C, Colston A, Cordel C, Lightowlers MW, Ngowi HA. Performance of Ag-ELISA in the diagnosis of Taenia solium cysticercosis in naturally infected pigs in Tanzania. Parasit Vectors 2020; 13:534. [PMID: 33109255 PMCID: PMC7590492 DOI: 10.1186/s13071-020-04416-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 10/21/2020] [Indexed: 12/23/2022] Open
Abstract
Background Taenia solium is a zoonotic parasite responsible for neurocysticercosis—a major cause of late-onset acquired epilepsy in humans. Lack of affordable, specific and sensitive diagnostic tools hampers control of the parasite. This study assessed the performance of an antigen detection enzyme-linked immunosorbent assay (Ag-ELISA) in the diagnosis of viable T. solium cysticercosis in naturally infected slaughter-age pigs in an endemic area in Tanzania. Methods A total of 350 pigs were bled before they were slaughtered and their carcases examined. Serum was analyzed for circulating antigens by using a monoclonal antibody-based B158/B60 Ag-ELISA. Each carcase was examined for the presence of Taenia hydatigena cysticerci and half carcase musculature together with the whole brain, head muscles, tongue, heart and diaphragm were sliced with fine cuts (< 0.5 cm) to reveal and enumerate T. solium cysticerci. Half carcase dissection can detect at least 84% of infected pigs. Prevalence and their 95% confidence intervals (CI) were calculated in Stata 12. Sensitivity, specificity, predictive values and likelihood ratios were determined. Results Twenty–nine pigs (8.3%, 95% CI: 5.6–11.7%) had viable T. solium cysticerci while 11 pigs had T. hydatigena cysticerci (3.1%, 95% CI: 1.6–5.5%). No co-infection was observed. Sixty-eight pigs (19.4%, 95% CI: 15.4–20%) tested positive on Ag-ELISA; of these, 24 had T. solium cysticerci and 7 had T. hydatigena cysticerci. Sensitivity and specificity were determined to be 82.7% and 86.3%, respectively. Positive and negative predictive values were 35.2% and 98.2%, respectively. Likelihood ratios for positive and negative Ag-ELISA test results were 6.0 and 0.2, respectively. There was a significant positive correlation between the titre of circulating antigens and intensity of T. solium cysticerci (r(348) = 0.63, P < 0.001). Conclusions The Ag-ELISA test characteristics reported in this study indicate that the test is more reliable in ruling out T. solium cysticercosis in pigs, than in confirming it. Hence, a negative result will almost certainly indicate that a pig has no infection, but a positive result should always be interpreted with caution. Estimates of T. solium prevalence based on Ag-ELISA results should, therefore, be adjusted for test performance characteristics and occurrence of T. hydatigena.![]()
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Affiliation(s)
| | - Maria V Johansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - James E D Mlangwa
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Ernatus M Mkupasi
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Uffe C Braae
- Department of Infectious Disease Epidemiology, Statens Serum Institut, Copenhagen, Denmark.,One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
| | - Chiara Trevisan
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Angela Colston
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Nairobi, Kenya
| | - Claudia Cordel
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Bloemfontein, Free State, South Africa
| | - Marshall W Lightowlers
- UVet, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee, VIC, Australia
| | - Helena A Ngowi
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
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Kabululu ML, Ngowi HA, Mlangwa JED, Mkupasi EM, Braae UC, Colston A, Cordel C, Poole EJ, Stuke K, Johansen MV. TSOL18 vaccine and oxfendazole for control of Taenia solium cysticercosis in pigs: A field trial in endemic areas of Tanzania. PLoS Negl Trop Dis 2020; 14:e0008785. [PMID: 33052939 PMCID: PMC7588121 DOI: 10.1371/journal.pntd.0008785] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 10/26/2020] [Accepted: 09/09/2020] [Indexed: 01/16/2023] Open
Abstract
A field trial was conducted in Tanzania to determine the effectiveness of TSOL18 vaccine used concurrently with oxfendazole (OFZ), and of OFZ alone, on T. solium cysticercosis determined by organ and half carcase dissection of slaughter age pigs. This study followed a quasi-experimental group design. Suitable trial sites were randomly allocated to either treatment group T1 (OFZ treatment alone [30mg/kg, Paranthic 10%]) or T2 (TSOL18 [1ml, Cysvax] plus OFZ). Three 4-monthly treatments were administered to eligible pigs. A random selection of pigs were necropsied at baseline and at endline, 2–3.5 months after the final treatment. Additionally, untreated pigs from T1 and T2 areas were necropsied at endline to provide contemporaneous comparisons with T1 and T2 pigs. Baseline prevalence of viable T. solium cysticerci for T1 was 25.5% (Exact 95% CI: 13.9, 40.3; n = 12/47), and for T2 was 12.0% (CI: 6.4, 20.0; n = 12/100). At endline, prevalence was 2.8% for T1 (CI: 0.1, 14.5, n = 1/36) and 0% for T2 (CI: 0, 4.7, n = 0/77). Among untreated pigs, three had viable cysticerci, one from T1 area (12.5%, CI: 0.3, 52.7; n = 1/8) and two from T2 area (5.7%, CI: 0.7, 19.2, n = 2/35). Fisher’s exact test showed significant changes in prevalence from baseline to endline in both groups (T1: p = 0.005, T2: p = 0.001). Firth’s penalized Maximum Likelihood method suggested the changes were not significant relative to their controls (T1: p = 0.245, T2: p = 0.076). These findings showed a significant reduction in the prevalence of viable cysticerci from baseline to endline after both interventions. However, the changes could not be definitively attributed to the interventions due, in part, to small numbers of control pigs. Concurrent administration of the TSOL18 and OFZ cleared infection among assessed pigs whereas infection remained after treatment with OFZ only. Further studies including larger sample sizes would be required for more definitive conclusions. A One Health approach is recommended for rapid and sustainable impact. The pork tapeworm T. solium affects the health and income of poor people in endemic areas. A pig vaccine—TSOL18, and a drug—oxfendazole (OFZ) present options for its control. In this study we assessed the effectiveness of the two tools against the parasite in pigs. We provided one group of pigs (T1) with a concurrent administration of TSOL18 and OFZ, and another group (T2) with OFZ only, in three rounds at 4 months intervals. We compared infection prevalence before and after the interventions by detection of cysticerci through carcase dissections. In addition, untreated pigs from the T1 and T2 areas were also sacrificed to serve as controls. We found a significant reduction in prevalence within the groups after the interventions. However, the reductions were not significant when compared with the reductions in the control groups, hence could not be definitively attributed to the interventions. Further, concurrent administration of TSOL18 and OFZ cleared infection among assessed pigs whereas OFZ alone did not clear the infection. Further studies would be required to make more definitive conclusions. We advocate for a One Health approach for a more rapid and sustainable impact.
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Affiliation(s)
- Mwemezi L. Kabululu
- Tanzania Livestock Research Institute (TALIRI)—Uyole, Mbeya, Tanzania
- * E-mail:
| | - Helena A. Ngowi
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - James E. D. Mlangwa
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Ernatus M. Mkupasi
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Uffe C. Braae
- Department of Infectious Disease Epidemiology, Statens Serum Institut, Copenhagen, Denmark
- One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
| | - Angela Colston
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Nairobi, Kenya
| | - Claudia Cordel
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Bloemfontein, Free State, South Africa
| | - Elizabeth J. Poole
- Statistics for Sustainable Development (Stats4SD), Reading, United Kingdom
| | - Kristin Stuke
- Global Alliance for Livestock Veterinary Medicines (GALVmed), Nairobi, Kenya
| | - Maria V. Johansen
- Section for Parasitology and Aquatic Pathobiology, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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Krecek RC, Rabinowitz PM, Conrad PA. Demystifying and Demonstrating the Value of a One Health Approach to Parasitological Challenges. Vet Parasitol 2020; 287:109202. [PMID: 33045550 DOI: 10.1016/j.vetpar.2020.109202] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 08/06/2020] [Indexed: 01/20/2023]
Abstract
The One Health approach recognizes the interconnectedness of human, animal, and ecosystem health and encourages collaboration between diverse disciplines to address complex health problems. In this paper, 3 academics, with diverse training, experience and backgrounds who each work on different pathogenic parasites, will share their stories of tackling parasitic challenges by applying a One Health approach. The pathogenic parasites to be discussed include the helminth Taenia solium and protozoans Giardia, Theileria, Babesia, Neospora and Toxoplasma species. The 3 narratives focus on research and clinical case-based challenges and illustrate where collaboration between human, animal, and environmental health scientists either has or could lead to improved control of human and animal health as well as important research discoveries. The need for better evaluation of interventions and scientific evidence to support changes in clinical practice and encourage enhanced collaboration between human and veterinary clinicians, as well as new governmental policies to improve public and wildlife health, are described. The need for a range of evidence-based metrics to monitor the success and impact of the One Health approach to veterinary parasitology is also discussed.
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Affiliation(s)
- Rosina C Krecek
- 4302 Berwick Place, College Station, Texas 77845, United States; Department of Zoology, University of Johannesburg, Auckland Park, South Africa
| | - Peter M Rabinowitz
- Departments of Environmental and Occupational Health Sciences, Global Health, Family Medicine, University of Washington Center for One Health Research, 1959 NE Pacific Street HSB F551, Box 357234, Seattle, Washington 98195, United States
| | - Patricia A Conrad
- One Health Institute and Department of Pathology, Microbiology & Immunology, School of Veterinary Medicine, 1 Shields Avenue, University of California Davis, Davis, CA 95616, United States
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11
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Taenia solium insulin receptors: promising candidates for cysticercosis treatment and prevention. Acta Trop 2020; 209:105552. [PMID: 32485167 DOI: 10.1016/j.actatropica.2020.105552] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 11/23/2022]
Abstract
Insulin signaling pathway is an ancient and highly conserved pathway known to play critical roles in cell growth, control and metabolic regulation. In this study, we identified and characterized two insulin receptor genes (TsIR-1316 and TsIR-4810) from Taenia solium. TsIR-1316 was grouped with E. multilocularis insulin receptor (EmIR-1) and TsIR-4810 was closer to Taenia pisiformis insulin-like growth factor receptor (TpIR) on the same branch with a very high bootstrap value. TsIR-1316 was located on the integument of larvae and adult worms, as well as the ovary of adults and eggs. Alternatively, TsIR-4810 was located in the parenchyma and reproductive organs of the adult worms. By using in vitro cultivation systems with Cysticercus pisiformis as a model, we demonstrated that anti-TsIRs-LBD antibodies could effectively block the insulin signaling pathway, resulting in reduced phosphorylation of the insulin receptor as well as lower levels of glucose uptake and glycogen synthesis. The rabbits immunized with TsIR-1316-LBD, TsIR-4810-LBD and TsIR-1316-LBD + TsIR-4810-LBD produced protection against infection of T. pisiformis as demonstrated by a 94.6%, 96% and 80% reduction of establishment of larvae, respectively. These data suggested that TsIR-1316-LBD and TsIR-4810-LBD are promising vaccine candidates or novel drug targets against swine cysticercosis.
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12
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Pray IW, Wakeland W, Pan W, Lambert WE, Garcia HH, Gonzalez AE, O'Neal SE. Understanding transmission and control of the pork tapeworm with CystiAgent: a spatially explicit agent-based model. Parasit Vectors 2020; 13:372. [PMID: 32709250 PMCID: PMC7379812 DOI: 10.1186/s13071-020-04226-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 07/14/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The pork tapeworm, Taenia solium, is a serious public health problem in rural low-resource areas of Latin America, Africa and Asia, where the associated conditions of nuerocysticercosis (NCC) and porcine cysticercosis cause substantial health and economic harms. An accurate and validated transmission model for T. solium would serve as an important new tool for control and elimination, as it would allow for comparison of available intervention strategies, and prioritization of the most effective strategies for control and elimination efforts. METHODS We developed a spatially-explicit agent-based model (ABM) for T. solium ("CystiAgent") that differs from prior T. solium models by including a spatial framework and behavioral parameters such as pig roaming, open human defecation, and human travel. In this article, we introduce the structure and function of the model, describe the data sources used to parameterize the model, and apply sensitivity analyses (Latin hypercube sampling-partial rank correlation coefficient (LHS-PRCC)) to evaluate model parameters. RESULTS LHS-PRCC analysis of CystiAgent found that the parameters with the greatest impact on model uncertainty were the roaming range of pigs, the infectious duration of human taeniasis, use of latrines, and the set of "tuning" parameters defining the probabilities of infection in humans and pigs given exposure to T. solium. CONCLUSIONS CystiAgent is a novel ABM that has the ability to model spatial and behavioral features of T. solium transmission not available in other models. There is a small set of impactful model parameters that contribute uncertainty to the model and may impact the accuracy of model projections. Field and laboratory studies to better understand these key components of transmission may help reduce uncertainty, while current applications of CystiAgent may consider calibration of these parameters to improve model performance. These results will ultimately allow for improved interpretation of model validation results, and usage of the model to compare available control and elimination strategies for T. solium.
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Affiliation(s)
- Ian W Pray
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, OR, USA.
| | - Wayne Wakeland
- Systems Science Program, Portland State University, Portland, OR, USA
| | - William Pan
- Global Health Institute, Duke University, Durham, NC, USA
| | - William E Lambert
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, OR, USA
| | - Hector H Garcia
- School of Sciences, Department of Microbiology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Armando E Gonzalez
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Seth E O'Neal
- School of Public Health, Oregon Health & Science University and Portland State University, Portland, OR, USA
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13
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Møller KS, Ngowi H, Magnussen P, Magne J, Kabululu M, Johansen MV. The effect of temperature and time on the viability of Taenia solium metacestodes in pork. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2020; 21:100436. [PMID: 32862912 DOI: 10.1016/j.vprsr.2020.100436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/29/2020] [Accepted: 07/14/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Taenia solium taeniosis is a growing health problem in large parts of the world including Sub-Saharan Africa. Humans are infected by eating undercooked pork with T. solium metacestodes, which cause taeniosis. The aim of the present study was to assess the effect of increasing temperatures on T. solium metacestode viability in pork. METHODS Heavily T. solium infected pieces of pork were cooked in a water-bath at five different temperatures (40 °C, 50 °C, 60 °C, 70 °C and 80 °C) for 10-60 min. At each temperature/time point, five 5x5x5 cm pieces of pork fitted with thermometers at the core were placed in the water-bath. Controls were kept at 5 °C throughout exposure. After exposure, approximately 100 intact metacestodes were harvested and after a maximum of 6 h incubation at 37 °C in a culture media consisting of 50% porcine bile and 50% saline, the metacestodes were evaluated for viability. RESULTS The metacestodes were fully viable after cooking at a core temperature of 40 °C for up to an hour. The metacestodes were non-viable after cooking for >40 min at a core temperature over 50 °C. All metacestodes were dead after cooking for 30 min at a core temperature of 60 °C; at 70 °C, non-viability was found after 20 min and all metacestodes were dead after 10 min cooking at 80 °C. CONCLUSION Findings showed that pork pieces cooked at >80 °C for >10 min proved safe for human consumption. This means that dishes consisting of pork pieces in sizes not greater than a 5 cm cube which are immersed in continuously boiling water for at least 10 min would be safe to eat. However, pork deep-fried in oil may entail a risk due to generally shorter cooking time. More research on the cooking practises is needed in order to produce safe guidelines for risk-free pork consumption.
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Affiliation(s)
- Karen Schou Møller
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 100, 1870 Frederiksberg C, Denmark..
| | - Helena Ngowi
- Department of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P.O. Box 3021, Morogoro, Tanzania
| | - Pascal Magnussen
- Centre for Medical Parasitology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Building 7-11-50, Blegdamsvej 3 B, 2200 Copenhagen, N, Denmark..
| | - Jeanette Magne
- Danish School of Education (DPU), Campus Emdrup, Tuborgvej 164, Building D 115, 2400 Copenhagen, NV, Denmark..
| | - Mwemezi Kabululu
- Tanzania Livestock Research Institute (TALIRI) - Uyole, P.O. Box 6191, Mbeya, Tanzania
| | - Maria Vang Johansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 100, 1870 Frederiksberg C, Denmark
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14
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Garcia HH, Gonzalez AE, Gilman RH. Taenia solium Cysticercosis and Its Impact in Neurological Disease. Clin Microbiol Rev 2020; 33:e00085-19. [PMID: 32461308 PMCID: PMC7254859 DOI: 10.1128/cmr.00085-19] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Taenia solium neurocysticercosis (NCC) is endemic in most of the world and contributes significantly to the burden of epilepsy and other neurological morbidity. Also present in developed countries because of immigration and travel, NCC is one of few diseases targeted for eradication. This paper reviews all aspects of its life cycle (taeniasis, porcine cysticercosis, human cysticercosis), with a focus on recent advances in its diagnosis, management, and control. Diagnosis of taeniasis is limited by poor availability of immunological or molecular assays. Diagnosis of NCC rests on neuroimaging findings, supported by serological assays. The treatment of NCC should be approached in the context of the particular type of infection (intra- or extraparenchymal; number, location, and stage of lesions) and has evolved toward combined symptomatic and antiparasitic management, with particular attention to modulating inflammation. Research on NCC and particularly the use of recently available genome data and animal models of infection should help to elucidate mechanisms of brain inflammation, damage, and epileptogenesis.
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Affiliation(s)
- Hector H Garcia
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - Armando E Gonzalez
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Robert H Gilman
- Department of International Health, Johns Hopkins School of Public Health, Baltimore, Maryland, USA
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15
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Lescano AG, Pray IW, Gonzalez AE, Gilman RH, Tsang VCW, Gamboa R, Guezala MC, Aybar V, Rodriguez S, Moulton LH, Leontsini E, Gonzalvez G, O'Neal SE, Garcia HH, For The Cysticercosis Working Group In Peru. Clustering of Necropsy-Confirmed Porcine Cysticercosis Surrounding Taenia solium Tapeworm Carriers in Peru. Am J Trop Med Hyg 2019; 100:314-322. [PMID: 30560769 DOI: 10.4269/ajtmh.18-0296] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The pork tapeworm, Taenia solium, is among the leading causes of preventable epilepsy in the world and is common in rural areas of developing countries where sanitation is limited and pigs have access to human feces. Prior studies in rural villages of Peru have observed clusters of T. solium cysticercosis among pigs that live near human tapeworm carriers. Such spatial analyses, however, have been limited by incomplete participation and substandard diagnostic tests. In this study, we evaluated the association between necropsy-confirmed cysticercosis in pigs and their distance to T. solium tapeworm carriers in six villages in northern Peru. A total of six (1.4%) tapeworm carriers were detected using copro-antigen enzyme-linked immunosorbent assay and seven of 10 (70%) pigs belonging to the tapeworm carriers were found with viable cyst infection on necropsy. This was significantly greater than the prevalence of viable cyst infection among pigs living < 500 m (11%) and > 500 m (0.5%) from a tapeworm carrier (P < 0.001 for distance trend). Similar statistically significant prevalence gradients were observed after adjustment for possible confounders and for other pig-level outcomes including infection with > 10 viable cysts, degenerated cyst infection, and serological outcomes. This investigation confirms that porcine cysticercosis clusters strongly around tapeworm carriers in endemic rural regions of northern Peru and supports interventions that target these hotspots.
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Affiliation(s)
- Andres G Lescano
- Emerging Diseases and Climate Change Research Unit, School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru.,Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Ian W Pray
- School of Public Health, Oregon Health and Science University and Portland State University, Portland, Oregon
| | - Armando E Gonzalez
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Robert H Gilman
- Research Department, Asociación Benéfica PRISMA (Proyectos en Informatica, Salud, Medicina y Agricultura), Lima, Peru.,Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Department of Microbiology, School of Sciences, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Victor C W Tsang
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ricardo Gamboa
- Center for Global Health Tumbes, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - M Claudia Guezala
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Viterbo Aybar
- School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru.,Center for Global Health Tumbes, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Silvia Rodriguez
- Instituto de Ciencias Neurológicas, Cysticercosis Unit, Lima, Peru
| | - Lawrence H Moulton
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Elli Leontsini
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Guillermo Gonzalvez
- Department of Microbiology, School of Sciences, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Seth E O'Neal
- School of Public Health, Oregon Health and Science University and Portland State University, Portland, Oregon
| | - Hector H Garcia
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,Instituto de Ciencias Neurológicas, Cysticercosis Unit, Lima, Peru.,Department of Microbiology, School of Sciences, Universidad Peruana Cayetano Heredia, Lima, Peru.,Center for Global Health Tumbes, Universidad Peruana Cayetano Heredia, Lima, Peru
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16
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Poudel I, Sah K, Subedi S, Kumar Singh D, Kushwaha P, Colston A, Gauci CG, Donadeu M, Lightowlers MW. Implementation of a practical and effective pilot intervention against transmission of Taenia solium by pigs in the Banke district of Nepal. PLoS Negl Trop Dis 2019; 13:e0006838. [PMID: 30802248 PMCID: PMC6405169 DOI: 10.1371/journal.pntd.0006838] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 03/07/2019] [Accepted: 01/23/2019] [Indexed: 11/29/2022] Open
Abstract
Taenia solium is a zoonotic cestode parasite which causes human neurocysticercosis. Pigs transmit the parasite by acting as the intermediate host. An intervention was implemented to control transmission of T. solium by pigs in Dalit communities of Banke District, Nepal. Every 3 months, pigs were vaccinated with the TSOL18 recombinant vaccine (Cysvax, IIL, India)) and, at the same time, given an oral treatment with 30mg/kg oxfendazole (Paranthic 10% MCI, Morocco). The prevalence of porcine cysticercosis was determined in both an intervention area as well as a similar no intervention control area, among randomly selected, slaughter-age pigs. Post mortem assessments were undertaken both at the start and at the end of the intervention. Participants conducting the post mortem assessments were blinded as to the source of the animals being assessed. At the start of the intervention the prevalence of porcine cysticercosis was 23.6% and 34.5% in the control and intervention areas, respectively. Following the intervention, the prevalence of cysticercosis in pigs from the control area was 16.7% (no significant change), whereas no infection was detected after complete slicing of all muscle tissue and brain in animals from the intervention area (P = 0.004). These findings are discussed in relation to the feasibility and sustainability of T. solium control. The 3-monthly vaccination and drug treatment intervention in pigs used here is suggested as an effective and practical method for reducing T. solium transmission by pigs. The results suggest that applying the intervention over a period of years may ultimately reduce the number of tapeworm carriers and thereby the incidence of NCC. Neurocysticercosis is a disease caused by a parasitic infection of the brain. The parasite responsible, Taenia solium, is transmitted by pigs where human sanitation is poor and pigs roam freely. Neurocysticercosis is responsible for many cases of epilepsy in people living in poor, developing countries. The feasibility and sustainability of implementing control measures have been major impediments to reducing the incidence of neurocysticercosis. Recently, two new commercial products have become available which together offer the possibility of interrupting the parasite’s transmission by pigs–the TSOL18 vaccine (Cysvax, IIL, India) and an oxfendazole formulation (Paranthic 10%, MCI, Morocco) licensed for use in pigs for the treatment of cysticercosis. Here we describe the impact of implementing vaccination plus drug treatment of pigs in the Banke district of Nepal. The intervention eliminated the risk of transmission of T. solium by the animals vaccinated and treated during the trial. Application of the vaccination and drug treatment program used here, possibly with strategic use of anthelmintics also in the human population, is an effective option for reducing the incidence of neurocysticercosis in Nepal and elsewhere.
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Affiliation(s)
- Ishab Poudel
- Heifer International, Kathmandu, Nepal
- * E-mail: (IP); (MWL)
| | | | | | - Dinesh Kumar Singh
- Department of Pathology and Clinics (HOD), Tribhuvan University, Institute of Agriculture and Animal Science, Rampur Campus, Chitwan, Nepal
| | - Peetambar Kushwaha
- GALVmed, Unit 118 & 120 B, Jasola District Centre, Jasola, New Delhi, India
| | - Angela Colston
- GALVmed, Galana Plaza, Galana Road, Kilimani, Nairobi, Kenya
| | - Charles G. Gauci
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee Victoria, Australia
| | - Meritxell Donadeu
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee Victoria, Australia
| | - Marshall W. Lightowlers
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee Victoria, Australia
- * E-mail: (IP); (MWL)
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17
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Meester M, Swart A, Deng H, van Roon A, Trevisan C, Dorny P, Gabriël S, Vieira-Pinto M, Johansen MV, van der Giessen J. A quantitative risk assessment for human Taenia solium exposure from home slaughtered pigs in European countries. Parasit Vectors 2019; 12:82. [PMID: 30755275 PMCID: PMC6371533 DOI: 10.1186/s13071-019-3320-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 01/28/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Taenia solium, a zoonotic tapeworm, is responsible for about a third of all preventable epilepsy human cases in endemic regions. In Europe, adequate biosecurity of pig housing and meat inspection practices have decreased the incidence of T. solium taeniosis and cysticercosis. Pigs slaughtered at home may have been raised in suboptimal biosecurity conditions and slaughtered without meat inspection. As a result, consumption of undercooked pork from home slaughtered pigs could pose a risk for exposure to T. solium. The aim of this study was to quantify the risk of human T. solium exposure from meat of home slaughtered pigs, in comparison to controlled slaughtered pigs, in European countries. A quantitative microbial risk assessment model (QMRA) was developed and porcine cysticercosis prevalence data, the percentage of home slaughtered pigs, meat inspection sensitivity, the cyst distribution in pork and pork consumption in five European countries, Bulgaria, Germany, Poland, Romania and Spain, were included as variables in the model. This was combined with literature about cooking habits to estimate the number of infected pork portions eaten per year in a country. RESULTS The results of the model showed a 13.83 times higher prevalence of contaminated pork portions from home slaughtered pigs than controlled slaughtered pigs. This difference is brought about by the higher prevalence of cysticercosis in pigs that are home raised and slaughtered. Meat inspection did not affect the higher exposure from pork that is home slaughtered. Cooking meat effectively lowered the risk of exposure to T. solium-infected pork. CONCLUSIONS This QMRA showed that there is still a risk of obtaining an infection with T. solium due to consumption of pork, especially when pigs are reared and slaughtered at home, using data of five European countries that reported porcine cysticercosis cases. We propose systematic reporting of cysticercosis cases in slaughterhouses, and in addition molecularly confirming suspected cases to gain more insight into the presence of T. solium in pigs and the risk for humans in Europe. When more data become available, this QMRA model could be used to evaluate human exposure to T. solium in Europe and beyond.
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Affiliation(s)
- Marina Meester
- National Institute for Public Health and the Environment (RIVM), Center for Infectious Disease Control, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Arno Swart
- National Institute for Public Health and the Environment (RIVM), Center for Infectious Disease Control, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Huifang Deng
- National Institute for Public Health and the Environment (RIVM), Center for Infectious Disease Control, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Annika van Roon
- National Institute for Public Health and the Environment (RIVM), Center for Infectious Disease Control, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
| | - Chiara Trevisan
- Department of Biomedical Sciences, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium
| | - Pierre Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium
| | - Sarah Gabriël
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - Madalena Vieira-Pinto
- Department of Veterinary Medicine, Universidade de Trás-os-Montes e Alto Douro, UTAD, Quinta de Prados, 5000-801 Vila Real, Portugal
- CECAV, Centro de Ciência Animale Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal
| | - Maria Vang Johansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 100, 1870 Frederiksberg C, Denmark
| | - Joke van der Giessen
- National Institute for Public Health and the Environment (RIVM), Center for Infectious Disease Control, P.O. Box 1, 3720 BA Bilthoven, The Netherlands
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Gabriël S, Mwape K, Phiri I, Devleesschauwer B, Dorny P. Taenia solium control in Zambia: The potholed road to success. Parasite Epidemiol Control 2019; 4:e00082. [PMID: 30662967 PMCID: PMC6324015 DOI: 10.1016/j.parepi.2018.e00082] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 12/19/2022] Open
Abstract
The taeniosis/cysticercosis neglected zoonotic disease complex is caused by Taenia solium, and is associated with significant economic and public health impacts. This paper reviews the current knowledge on T. solium in Zambia and the control strategies already studied, covering almost 20 years of research, and explores the way forward. Studies on occurrence of porcine cysticercosis indicated very high prevalences, ranging from 15 to 34% based on detection of circulating antigens, and of 46% to 68% based on full carcass dissection in slaughter age pigs. Taeniosis prevalences have been reported to range from 6.3% to 12% based on copro-Ag-ELISA. Human cysticercosis prevalence results ranged from 5.8% to 13% based on serum Ag-ELISA, and from 34% to 39% based on sero-antibody detection. Later on, a study in people with epilepsy suggested neurocysticercosis to be the single most important cause of epilepsy in this T. solium endemic area, with 57% of the people with active epilepsy diagnosed with probable or definite neurocysticercosis. While the need to reduce the disease burden of T. solium in Zambia is obvious, the exact short and long term goals, and the strategies to achieve these goals, are not clear. We have selected the most promising control/elimination strategies from reviews and assessed these for feasibility via discussions with local stakeholders from both medical and veterinary sectors. The proposed measures were evaluated using the newly developed agent-based disease transmission model, cystiSim and optimised using Zambian demographic and disease data. As a control option, yearly porcine treatments were selected as best option, while the preferred strategy for elimination was determined to be the combination of human and porcine mass drug administration combined with porcine vaccination of all eligible people and pigs, in a schedule of six iterations of four monthly interventions. These interventions are currently being field tested, combined with education. Several other hurdles to control, such as cost and socio-political factors and the need for an improved advocacy and awareness creation are discussed.
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Affiliation(s)
- S. Gabriël
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Belgium
| | - K.E. Mwape
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - I.K. Phiri
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - B. Devleesschauwer
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Belgium
- Department of Epidemiology and Public Health, Sciensano, Brussels, Belgium
| | - P. Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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de Coster T, Van Damme I, Baauw J, Gabriël S. Recent advancements in the control of Taenia solium: A systematic review. Food Waterborne Parasitol 2018; 13:e00030. [PMID: 32095601 PMCID: PMC7034013 DOI: 10.1016/j.fawpar.2018.e00030] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 01/07/2023] Open
Abstract
The combined health and economic impact of Taenia solium urges for control and, if possible, elimination of this neglected parasitic zoonosis. Up till now there is still no consensus about the most cost-effective and feasible approaches for control. The objective of this systematic review is to identify and summarize the evidence in English scientific literature on the control and elimination of T. solium since 2014, based on the rapidly evolving field of evidence on control and elimination of T. solium. The search resulted in the identification of 458 records of which 31 were included, covering 13 field trials and 18 articles containing experimental data, mathematical models, and other information directly relevant the control of T. solium. Recent field studies confirm that combinations of interventions or multiple rounds are more successful in obtaining rapid reductions in transmission and parasite occurrence, with the quick impact of the combination of human and pig treatment confirmed in a South Asian and Peruvian context. Moreover, elimination of transmission through a one-year intensive program, combining human and pig treatment/vaccination was described in a Peruvian study. Recent studies also provide more data on the positive impact of specific health education, as well as newly developed electronic educational tools, providing opportunities for area specific community-engaged participatory interventions. Once control has been achieved, monitoring of migration of both potentially infected people and pigs from outside the control area is important for sustained disease control. Combined intervention field studies demonstrate sharp decreases in disease occurrence. New, specific, efficient, electronic educational tools are available. Elimination of Taenia solium in a Peruvian endemic area has been described. Integration of Taenia solium control in other NTD control programs can be effective.
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Affiliation(s)
- T de Coster
- Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - I Van Damme
- Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - J Baauw
- Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - S Gabriël
- Ghent University, Faculty of Veterinary Medicine, Department of Veterinary Public Health and Food Safety, Salisburylaan 133, 9820 Merelbeke, Belgium
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Symeonidou I, Arsenopoulos K, Tzilves D, Soba B, Gabriël S, Papadopoulos E. Human taeniasis/cysticercosis: a potentially emerging parasitic disease in Europe. Ann Gastroenterol 2018; 31:406-412. [PMID: 29991885 PMCID: PMC6033766 DOI: 10.20524/aog.2018.0260] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 01/30/2018] [Indexed: 12/04/2022] Open
Abstract
Taenia saginata (T. saginata)/Taenia solium (T. solium) taeniasis/cysticercosis disease complexes remain a significant challenge for food safety and public health. Human taeniasis is an infectious disease caused by the ingestion of the metacestode larval stage, the cysticerci of T. saginata in beef or T. solium in pork. Humans can also become infected via the ingestion of T. solium eggs. In this case, the cysticerci can establish in the central nervous system, causing the infection called neurocysticercosis. T. solium is of higher importance than T. saginata because the former species can cause neurocysticercosis in humans, a major cause of neurological morbidity in the world. The taeniasis/cysticercosis complex is included in the list of neglected zoonotic diseases by the World Health Organization and Food and Agriculture Organization, with T. solium being the number one foodborne parasite; it occurs mostly in developing countries, such as regions of Asia, Africa and Latin America, where the disease remains endemic. Long absent in Western Europe and other developed countries, cysticercosis has been recently re-emerged as a result of immigration, travel and commerce. In this review, cysticercosis is presented with special emphasis on some aspects of this neglected disease: the main clinical manifestations, risk factors and epidemiology. In addition, any recent advances in diagnostic approaches and treatment are discussed. Finally, the complexities involved in the control of the disease and the need to revise current management strategies are highlighted.
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Affiliation(s)
- Isaia Symeonidou
- Laboratory of Parasitology and Parasitic Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece (Isaia Symeonidou, Konstantinos Arsenopoulos, Elias Papadopoulos)
| | - Konstantinos Arsenopoulos
- Laboratory of Parasitology and Parasitic Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece (Isaia Symeonidou, Konstantinos Arsenopoulos, Elias Papadopoulos)
| | - Dimitrios Tzilves
- Gastroenterology Department, Theageneio Hospital, Thessaloniki, Greece (Dimitrios Tzilves)
| | - Barbara Soba
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Slovenia (Barbara Soba)
| | - Sarah Gabriël
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium (Sarah Gabriël)
| | - Elias Papadopoulos
- Laboratory of Parasitology and Parasitic Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece (Isaia Symeonidou, Konstantinos Arsenopoulos, Elias Papadopoulos)
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Effectiveness of an integrated intervention in the control of endo- and ectoparasites of pigs kept by smallholder farmers in Mbeya rural and Mbozi districts, Tanzania. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2018; 13:64-73. [PMID: 31014892 DOI: 10.1016/j.vprsr.2018.03.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 02/02/2018] [Accepted: 03/31/2018] [Indexed: 11/23/2022]
Abstract
This study was conducted to evaluate effectiveness of an integrated management intervention in the control of endo- and ectoparasites of pigs kept by smallholder farmers in Mbeya Rural and Mbozi districts of southern highlands of Tanzania. A repeated cross-sectional group randomization design was employed, with 10 villages in the intervention group and six villages in the control group. The intervention consisted of improving pig confinement, feeds and feeding practices, and strategic anthelmintic treatment of pigs with oxfendazole, to primarily control Taenia solium (porcine) cysticercosis and nematodes; and with ivermectin to control ectoparasites and nematodes. Blood and faecal samples, ectoparasite specimens and skin scrapings were collected at baseline and two follow-up rounds, at an interval of seven months. A total of 482, 460 and 421 pigs were sampled in 221, 196 and 139 households at baseline, first and second follow-up visits respectively. Sero-prevalence of PC, prevalence and burden of gastrointestinal (GI) nematodes and prevalence of ectoparasites were determined using Ag-ELISA, McMaster faecal egg counting technique and body searches/skin scrapings, respectively. Mann Whitney test was used to measure intervention effect by comparing changes from baseline values of prevalence and faecal egg counts between the two groups. No significant difference (p > 0.05) was observed between the two groups, in changes from baseline of sero-prevalence of PC. The intervention significantly reduced prevalence of Trichuris suis (p = 0.044) and mean faecal egg counts of Ascaris suum (p = 0.02) from baseline to first follow-up. The intervention showed a substantial effect on the prevalence of ectoparasites as it significantly reduced overall prevalence of ectoparasites (p = 0.026), lice (p = 0.045), ticks (p = 0.049) and mites (p = 0.013) from baseline to first follow-up, and prevalence of ectoparasites, lice and mites from baseline to second follow-up (p = 0.052, p = 0.03, p = 0.017 respectively). This study has demonstrated a moderate effect of the intervention on controlling GI nematodes and ectoparasites, but no effect on sero-prevalence of PC. The reported ineffectiveness of the intervention against PC is probably an underestimation because serology is not able to provide quantitative data. It may also be a result of reduced compliance as this was a field study. Nevertheless, further studies are needed to better understand transmission dynamics of PC and explore One Health approaches including treatment of the human population against taeniosis to better secure public health.
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Donadeu M, Fahrion AS, Olliaro PL, Abela-Ridder B. Target product profiles for the diagnosis of Taenia solium taeniasis, neurocysticercosis and porcine cysticercosis. PLoS Negl Trop Dis 2017; 11:e0005875. [PMID: 28892472 PMCID: PMC5608417 DOI: 10.1371/journal.pntd.0005875] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/21/2017] [Accepted: 08/17/2017] [Indexed: 11/19/2022] Open
Abstract
Target Product Profiles (TPPs) are process tools providing product requirements to guide researchers, developers and manufacturers in their efforts to develop effective and useful products such as biologicals, drugs or diagnostics. During a WHO Stakeholders Meeting on Taenia solium diagnostics, several TPPs were initiated to address diagnostic needs for different stages in the parasite's transmission (taeniasis, human and porcine cysticercosis). Following the meeting, draft TPPs were completed and distributed for consultation to 100 people/organizations, including experts in parasitology, human and pig cysticercosis, diagnostic researchers and manufacturers, international organizations working with neglected or zoonotic diseases, Ministries of Health and Ministries of Livestock in some of the endemic countries, WHO regional offices and other interested parties. There were 53 respondents. All comments and feedback received were considered and discussions were held with different experts according to their area of expertise. The comments were consolidated and final TPPs are presented here. They are considered to be live documents which are likely to undergo review and updating in the future when new knowledge and technologies become available.
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Affiliation(s)
- Meritxell Donadeu
- The University of Melbourne, Faculty of Veterinary and Agricultural Sciences, Veterinary Clinical Centre, Werribee, Victoria, Australia
- Initiative for Neglected Animal Diseases (INAND), Midrand, South Africa
- * E-mail:
| | - Anna S. Fahrion
- Department of Control of Neglected Tropical Diseases, World Health Organization, Genève, Switzerland
| | - Piero L. Olliaro
- Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Genève, Switzerland
| | - Bernadette Abela-Ridder
- Department of Control of Neglected Tropical Diseases, World Health Organization, Genève, Switzerland
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Okello AL, Thomas LF. Human taeniasis: current insights into prevention and management strategies in endemic countries. Risk Manag Healthc Policy 2017; 10:107-116. [PMID: 28615981 PMCID: PMC5461055 DOI: 10.2147/rmhp.s116545] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Human taeniasis is a zoonotic condition resulting from infection with the adult stages of Taenia saginata ("beef tapeworm"), Taenia solium ("pork tapeworm") or Taenia asiatica ("Asian tapeworm"). Although these parasites have a worldwide distribution, the overwhelming burden is felt by communities in low- and middle-income countries. This is particularly true for T. solium, whereby infection of the central nervous system with the larval stage of the parasite (neurocysticercosis) is a major cause of acquired epilepsy in low-resource settings. With a focus on endemic countries, this review provides an insight into the prevention and management of human taeniasis, concluding with some recent case studies describing their implementation. Discussion of the opportunities and challenges regarding current fecal and serological diagnostic assays for detecting Taenia spp. highlights the importance of accurate and accessible diagnostic options for the field situation. The lack of long-term impact on the parasites' lifecycle from human anthelmintic treatment, coupled with the propensity for adverse reactions, highlights the importance of a "two-pronged" approach that considers the relevant animal hosts, particularly in the case of T. solium. Aside from the therapeutic options, this review reiterates the importance of adequate assessment and consideration of the associated behavioral and policy aspects around sanitation, hygiene and meat inspection that have been shown to support parasite control, and potential elimination, in endemic regions.
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Affiliation(s)
- Anna L Okello
- Division of Infection and Pathway Medicine, Edinburgh Medical School, Biomedical Sciences College of Medicine and Veterinary Medicine, University of Edinburgh, Scotland
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Designing a Minimal Intervention Strategy to Control Taenia solium. Trends Parasitol 2017; 33:426-434. [DOI: 10.1016/j.pt.2017.01.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/13/2017] [Accepted: 01/23/2017] [Indexed: 11/21/2022]
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Kungu JM, Dione MM, Ejobi F, Ocaido M, Grace D. Risk factors, perceptions and practices associated with Taenia solium cysticercosis and its control in the smallholder pig production systems in Uganda: a cross-sectional survey. BMC Infect Dis 2017; 17:1. [PMID: 28049444 PMCID: PMC5209818 DOI: 10.1186/s12879-016-2122-x] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 12/14/2016] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Prevalence studies report Taenia solium cysticercosis in pig and human populations in Uganda. However, the factors influencing occurrence in smallholder pig production systems are not well documented and little is known about farmers' perceptions of T. solium cysticercosis or farmer practices that could reduce transmission. METHODS To determine the risk factors, perceptions and practices regarding T. solium cysticercosis, a household survey using a semi-structured questionnaire was conducted in 1185 households in the rural and urban pig production systems in Masaka, Mukono and Kamuli Districts. Logistic regression was used to measure associations of risk factors with infection. Performance scores were calculated to summarise perceptions and practices of farmers regarding taeniosis, human cysticercosis and porcine cysticercosis as well as farmer behavior related to control or breaking transmission. RESULTS Pig breed type, farmers' knowledge about transmission, sources of water used, and pig keeping homes where family members were unable to use the latrine were all significantly associated with T. solium cysticercosis in pigs. Performance scores indicated that farmers were more aware of taeniosis (63.0%; 95% Confidence Interval 60.0-65.8) than human or porcine cysticercosis; only three farmers (0.3%, 95% CI = 0.1-0.8) had knowledge on all three conditions. More farmers reported that they dewormed pigs (94.1%) than reported deworming themselves and their family members (62.0%). Albendazole was the most commonly used drug for deworming both pigs and humans (85.0 and 81.5% respectively). Just over half (54.6%) of the farmers interviewed had clean water near the latrines for washing hands. Of these, only 41.9% used water with soap to wash hands after latrine use. CONCLUSION Factors that significantly influenced occurrence of T. solium cysticercosis in pigs were identified. Farmers had some knowledge about the disease but did not link taeniosis, human cysticercosis, and porcine cysticercosis. Therefore, there is need to employ strategies that raise awareness and interrupt transmission.
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Affiliation(s)
- Joseph M. Kungu
- National Livestock Resources Research Institute, P. O. Box 96, Tororo, Uganda
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P. O. Box 7062, Kampala, Uganda
- International Livestock Research Institute, P.O. Box 24384, Kampala, Uganda
| | - Michel M. Dione
- International Livestock Research Institute, P.O. Box 24384, Kampala, Uganda
| | - Francis Ejobi
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P. O. Box 7062, Kampala, Uganda
| | - Michael Ocaido
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, P. O. Box 7062, Kampala, Uganda
| | - Delia Grace
- International Livestock Research Institute, P.O. Box 30709, Nairobi, Kenya
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Gabriël S, Dorny P, Mwape KE, Trevisan C, Braae UC, Magnussen P, Thys S, Bulaya C, Phiri IK, Sikasunge CS, Makungu C, Afonso S, Nicolau Q, Johansen MV. Control of Taenia solium taeniasis/cysticercosis: The best way forward for sub-Saharan Africa? Acta Trop 2017; 165:252-260. [PMID: 27140860 DOI: 10.1016/j.actatropica.2016.04.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 11/15/2022]
Abstract
Taenia solium taeniasis/cysticercosis is a neglected parasitic zoonosis with significant economic and public health impacts. Control measures can be broadly grouped into community health education, improvements in hygiene and sanitary conditions, proper meat handling at household and community level, improved standards of meat inspection, pig management, treatment of individual patients and possibly human populations, and treatment and/or vaccination of porcine populations. This manuscript looks critically into currently existing control options and provides suggestions on which (combination of) tools would be most effective in the control of T. solium taeniasis/cysticercosis in sub-Saharan Africa. Field data and disease transmission simulations suggest that implementation of a single intervention control strategy will not lead to a satisfactory reduction of disease morbidity or transmission. A feasible strategy to combat T. solium taeniasis/cysticercosis would include a combination of approaches focussing on both human (health education and treatment) and animal host (management, treatment and vaccination), which can vary for different communities and different geographical locations. Selection of the specific strategy depends on cost-effectiveness analyses based on solid field data, currently unavailable, though urgently needed; as well as on health priorities and resources of the country. A One Health approach involving medical, veterinary, environmental and social sectors is essential for T. solium to be controlled and eventually eliminated. Finally the success of any intervention is largely dependent on the level of societal and political acceptance, commitment and engagement.
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Affiliation(s)
- S Gabriël
- Institute of Tropical Medicine, Antwerp, Belgium.
| | - P Dorny
- Institute of Tropical Medicine, Antwerp, Belgium; Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - K E Mwape
- School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - C Trevisan
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - U C Braae
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - P Magnussen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - S Thys
- Institute of Tropical Medicine, Antwerp, Belgium
| | - C Bulaya
- School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - I K Phiri
- School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - C S Sikasunge
- School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - C Makungu
- School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - S Afonso
- Faculty of Veterinary Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Q Nicolau
- Faculty of Veterinary Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - M V Johansen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
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Braae UC, Devleesschauwer B, Gabriël S, Dorny P, Speybroeck N, Magnussen P, Torgerson P, Johansen MV. CystiSim - An Agent-Based Model for Taenia solium Transmission and Control. PLoS Negl Trop Dis 2016; 10:e0005184. [PMID: 27984581 PMCID: PMC5161321 DOI: 10.1371/journal.pntd.0005184] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 11/14/2016] [Indexed: 11/19/2022] Open
Abstract
Taenia solium taeniosis/cysticercosis was declared eradicable by the International Task Force for Disease Eradication in 1993, but remains a neglected zoonosis. To assist in the attempt to regionally eliminate this parasite, we developed cystiSim, an agent-based model for T. solium transmission and control. The model was developed in R and available as an R package (http://cran.r-project.org/package=cystiSim). cystiSim was adapted to an observed setting using field data from Tanzania, but adaptable to other settings if necessary. The model description adheres to the Overview, Design concepts, and Details (ODD) protocol and consists of two entities—pigs and humans. Pigs acquire cysticercosis through the environment or by direct contact with a tapeworm carrier's faeces. Humans acquire taeniosis from slaughtered pigs proportional to their infection intensity. The model allows for evaluation of three interventions measures or combinations hereof: treatment of humans, treatment of pigs, and pig vaccination, and allows for customary coverage and efficacy settings. cystiSim is the first agent-based transmission model for T. solium and suggests that control using a strategy consisting of an intervention only targeting the porcine host is possible, but that coverage and efficacy must be high if elimination is the ultimate goal. Good coverage of the intervention is important, but can be compensated for by including an additional intervention targeting the human host. cystiSim shows that the scenarios combining interventions in both hosts, mass drug administration to humans, and vaccination and treatment of pigs, have a high probability of success if coverage of 75% can be maintained over at least a four year period. In comparison with an existing mathematical model for T. solium transmission, cystiSim also includes parasite maturation, host immunity, and environmental contamination. Adding these biological parameters to the model resulted in new insights in the potential effect of intervention measures. Taenia solium is the leading cause of preventable epilepsy and the highest ranking foodborne parasite in terms of disease burden worldwide. Currently there are no large scale control programmes implemented against T. solium, but efficacious intervention tools are there, making control programmes the next step forward. Because of the zoonotic properties of the parasite, existing in both humans and pigs, a combination of intervention tools is likely to be needed. cystiSim is an agent-based disease model that provides insight into which intervention tools, and the frequency of administration of these tools, are needed to yield an effect on disease prevalence. cystiSim is a valuable tool in designing future control programmes and will assist in the elimination of T. solium as a public health problem.
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Affiliation(s)
- Uffe Christian Braae
- Section for Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
- * E-mail:
| | - Brecht Devleesschauwer
- Department of Public Health and Surveillance, Scientific Institute of Public Health (WIV-ISP), Brussels, Belgium
| | - Sarah Gabriël
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Pierre Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Niko Speybroeck
- Institute of Health and Society (IRSS), Université catholique de Louvain, Brussels, Belgium
| | - Pascal Magnussen
- Section for Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Paul Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Maria Vang Johansen
- Section for Parasitology and Aquatic Diseases, Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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Lightowlers MW, Garcia HH, Gauci CG, Donadeu M, Abela-Ridder B. Monitoring the outcomes of interventions against Taenia solium: options and suggestions. Parasite Immunol 2016; 38:158-69. [PMID: 26538513 PMCID: PMC4819694 DOI: 10.1111/pim.12291] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 10/26/2015] [Indexed: 11/27/2022]
Abstract
There is an increasing interest in reducing the incidence of human neurocysticercosis, caused by infection with the larval stage of Taenia solium. Several intervention trials are currently assessing various options for control of T. solium transmission. A critical aspect of these trials will be the evaluation of whether the interventions have been successful. However, there is no consensus about the most appropriate or valuable methods that should be used. Here, we undertake a critical assessment of the diagnostic tests which are currently available for human T. solium taeniasis and human and porcine cysticercosis, as well as their suitability for evaluation of intervention trial outcomes. Suggestions are made about which of the measures that are available for evaluation of T. solium interventions would be most suitable, and which methodologies are the most appropriate given currently available technologies. Suggestions are also made in relation to the most urgent research needs in order to address deficiencies in current diagnostic methods.
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Affiliation(s)
- M W Lightowlers
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Vic., Australia
| | - H H Garcia
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru.,Department of Microbiology, School of Sciences, Centre for Global Health-Tumbes, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - C G Gauci
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Vic., Australia
| | - M Donadeu
- Veterinary Clinical Centre, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Vic., Australia
| | - B Abela-Ridder
- Department of Control of Neglected Tropical Diseases, World Health Organization, Genève 27, Switzerland
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Anamnestic responses in pigs to the Taenia solium TSOL18 vaccine and implications for control strategies. Parasitology 2016; 143:416-20. [PMID: 26892239 DOI: 10.1017/s0031182016000202] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Specific antibody responses were assessed in pigs immunized with the Taenia solium vaccine TSOL18. Anti-TSOL18 responses were compared 2 weeks after secondary immunization, where the interval between primary and secondary immunization was 4, 8, 12, 16 or 20 weeks. All animals responded to the vaccine and there was no diminution in antibody responses in animals receiving their second injection after an interval up to 20 weeks. Pigs receiving vaccinations at an interval of 12 weeks developed significantly increased antibody responses compared with animals receiving immunizations 4 weeks apart (P = 0.046). The ability to deliver TSOL18 vaccination effectively where the revaccination schedule can be delayed for up to 12-16 weeks in pigs increases the options available for designing T. solium control interventions that incorporate TSOL18 vaccination.
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Singh AK, Singh SK, Singh A, Gupta KK, Khatoon J, Prasad A, Rai RP, Gupta RK, Tripathi M, Husain N, Prasad KN. Immune response to Taenia solium cysticerci after anti-parasitic therapy. Int J Parasitol 2015; 45:749-59. [DOI: 10.1016/j.ijpara.2015.05.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/14/2015] [Accepted: 05/18/2015] [Indexed: 01/11/2023]
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Productivity and parasitic infections of pigs kept under different management systems by smallholder farmers in Mbeya and Mbozi districts, Tanzania. Trop Anim Health Prod 2015; 47:1121-30. [PMID: 25934145 DOI: 10.1007/s11250-015-0836-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 04/16/2015] [Indexed: 10/23/2022]
Abstract
An on farm experiment was carried out to assess the effects of production systems on the performance of local pigs kept by smallholder farmers. Six villages from Mbeya and Mbozi districts, Tanzania were purposely selected based on the prominent pig production systems: free range, semi-confinement and total confinement. Fifteen pig keeping households were randomly selected from each village to participate in the study. A participatory rural appraisal and structured questionnaire were used for collecting information from the households on pig production and reproduction performance. In addition, a total of 180 weaner pigs, 2-3 months old, were purchased and randomly allocated to the 90 participating households. The pigs were subjected to three production systems: free range (M1), confinement with local diet (M2) and confinement with a compounded diet and anthelmintic treatment (M3). The anthelmintic treatment (piperazine citrate) was administered at 1 g per kg body weight. Faecal and blood samples were collected at month three of the experiment to assess the burden of intestinal helminths and sero-prevalence of Taenia solium cysticercosis, respectively. Sows kept under free range system were reported to have smaller litter size both at farrowing and at weaning compared to those kept under confinement. The experiment showed pigs under M3 had higher (P < 0.05) liveweight gains (136 g/day) compared to pigs in M2 (73 g/day) and M1 (68 g/day). In addition, pigs in M3 had higher body length and heart girth size with the feed to gain ratio of 8.5. Free range pigs tended to have lower faecal egg counts for most worm species compared to permanently confined pigs. Sero-prevalence of Taenia solium cysticercosis was 26%, with village prevalence ranging from 8 to 52%. Although pigs kept in M3 performed better than the rest, the compounded feed was too expensive for the farmers to afford. Locally available feed types combined with vitamin and mineral supplements may be a more sustainable option.
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Mahanty S, Orrego MA, Mayta H, Marzal M, Cangalaya C, Paredes A, Gonzales-Gustavson E, Arroyo G, Gonzalez AE, Guerra-Giraldez C, García HH, Nash TE. Post-treatment vascular leakage and inflammatory responses around brain cysts in porcine neurocysticercosis. PLoS Negl Trop Dis 2015; 9:e0003577. [PMID: 25774662 PMCID: PMC4361613 DOI: 10.1371/journal.pntd.0003577] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/29/2015] [Indexed: 11/18/2022] Open
Abstract
Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB) dysfunction, as determined by Evans blue (EB) extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue) and non stained (clear) cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα) were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3) was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model can be used to investigate mechanisms involved in host damaging inflammatory responses and agents or modalities that may control damaging post treatment inflammation. Neurocysticercosis is caused by infection of the brain with the larval (cyst) stage of the tape worm Taenia solium in humans and pigs. Antiparasitic drug treatment is compromised by worsening of neurological symptoms during therapy due to reactive inflammation triggered by the dying parasite. The immune mechanisms that cause this inflammation are poorly understood. In this study, we investigated the nature of inflammation after treatment in pigs naturally infected with T. solium cysts. Evans blue dye injected into infected pigs marks areas in the brain where the normally impermeable capillaries have become more permeable, allowing damaging cells and molecules to leak out into the brain. By microscopy and measurement of gene expression for inflammation-inducing immune mediators, we show that inflammation in the brain tissues around cysts is more severe with increased vessel leakage. Furthermore, the levels of these mediators increased after antiparasitic drug treatment. A significant implication of these findings is that it may be possible to inhibit the inflammation around parasites using drugs or biologics that inhibit these inflammatory pathways and, thereby, reduce local brain damage during treatment. These observations may also be applicable to other inflammatory conditions that affect the brain.
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Affiliation(s)
- Siddhartha Mahanty
- Laboratory of Parasitic Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
- * E-mail:
| | - Miguel Angel Orrego
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Holger Mayta
- Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Miguel Marzal
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Carla Cangalaya
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Adriana Paredes
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
| | | | - Gianfranco Arroyo
- Faculty of Veterinary Sciences, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Armando E. Gonzalez
- Faculty of Veterinary Sciences, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Cristina Guerra-Giraldez
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
- Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Hector H. García
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
- Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurologicas, Lima, Peru
| | - Theodore E. Nash
- Laboratory of Parasitic Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Laboratory of Immunopathology, Universidad Peruana Cayetano Heredia, Lima, Peru
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Afonso SMS, Neves L, Pondja A, Macuamule C, Mukaratirwa S, Arboix M, Cristòfol C, Capece BPS. Efficacy of albendazole against Taenia multiceps larvae in experimentally infected goats. Vet Parasitol 2014; 206:304-7. [PMID: 25450723 DOI: 10.1016/j.vetpar.2014.09.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 09/23/2014] [Accepted: 09/28/2014] [Indexed: 11/24/2022]
Abstract
A controlled trial was conducted to evaluate the efficacy of three therapeutics regimes of albendazole (ABZ) against Taenia multiceps larvae in experimental infected goats. Forty-nine goats experimentally infected with 3000 T. multiceps eggs were selected and randomly divided into treatment or control groups. Treatment with 10mg/kg for 3 days for group 1 (G1), 10mg/kg for group 2 (G2) and 20mg/kg/day for group 3 (G3) was applied 2 months after infection; group 4 (G4) served as a control group. A treatment with doses of 10mg/kg/day for 3 days on group 5 (G5) and group 6 (G6) was used as control, 5 months after the infection. The efficacy of ABZ was assessed as percentage of non-viable cysts which were determined by morphologic characteristics, movement and methyl blue staining technique. The efficacy of ABZ against 2 months old cysts was significantly different from the control and were 90.3% (28/31), 72.7% (8/11) and 73.9% (14/19) for G1, G2 and G3, respectively. No differences were observed in cyst viability between treated and control groups for 5-month old cysts. The results in this study indicate that ABZ is effective in goats against 2-month-old cysts of T. multiceps larva located in tissues outside the brain.
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Affiliation(s)
- Sónia M S Afonso
- Faculdade de Veterinária, Universidade Eduardo Mondlane, Av. de Moçambique, km 1.5, P.O. Box 257, Maputo, Mozambique
| | - Luis Neves
- Faculdade de Veterinária, Universidade Eduardo Mondlane, Av. de Moçambique, km 1.5, P.O. Box 257, Maputo, Mozambique
| | - Alberto Pondja
- Faculdade de Veterinária, Universidade Eduardo Mondlane, Av. de Moçambique, km 1.5, P.O. Box 257, Maputo, Mozambique
| | - Cristiano Macuamule
- Faculdade de Veterinária, Universidade Eduardo Mondlane, Av. de Moçambique, km 1.5, P.O. Box 257, Maputo, Mozambique
| | - Samson Mukaratirwa
- School of Life Sciences, University of KwaZulu-Natal, Biological Science Building, Westville Campus, Durban 4000, South Africa
| | - Margarita Arboix
- Department of Pharmacology, Therapeutics and Toxicology, Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Carles Cristòfol
- Department of Pharmacology, Therapeutics and Toxicology, Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Bettencourt P S Capece
- Faculdade de Veterinária, Universidade Eduardo Mondlane, Av. de Moçambique, km 1.5, P.O. Box 257, Maputo, Mozambique.
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Evans blue staining reveals vascular leakage associated with focal areas of host-parasite interaction in brains of pigs infected with Taenia solium. PLoS One 2014; 9:e97321. [PMID: 24915533 PMCID: PMC4051593 DOI: 10.1371/journal.pone.0097321] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 04/18/2014] [Indexed: 11/19/2022] Open
Abstract
Cysticidal drug treatment of viable Taenia solium brain parenchymal cysts leads to an acute pericystic host inflammatory response and blood brain barrier breakdown (BBB), commonly resulting in seizures. Naturally infected pigs, untreated or treated one time with praziquantel were sacrificed at 48 hr and 120 hr following the injection of Evans blue (EB) to assess the effect of treatment on larval parasites and surrounding tissue. Examination of harvested non encapsulated muscle cysts unexpectedly revealed one or more small, focal round region(s) of Evans blue dye infiltration (REBI) on the surface of otherwise non dye-stained muscle cysts. Histopathological analysis of REBI revealed focal areas of eosinophil-rich inflammatory infiltrates that migrated from the capsule into the tegument and internal structures of the parasite. In addition some encapsulated brain cysts, in which the presence of REBI could not be directly assessed, showed histopathology identical to that of the REBI. Muscle cysts with REBI were more frequent in pigs that had received praziquantel (6.6% of 3736 cysts; n = 6 pigs) than in those that were untreated (0.2% of 3172 cysts; n = 2 pigs). Similar results were found in the brain, where 20.7% of 29 cysts showed histopathology identical to muscle REBI cysts in praziquantel-treated pigs compared to the 4.3% of 47 cysts in untreated pigs. Closer examination of REBI infiltrates showed that EB was taken up only by eosinophils, a major component of the cellular infiltrates, which likely explains persistence of EB in the REBI. REBI likely represent early damaging host responses to T. solium cysts and highlight the focal nature of this initial host response and the importance of eosinophils at sites of host-parasite interaction. These findings suggest new avenues for immunomodulation to reduce inflammatory side effects of anthelmintic therapy.
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Rasamoelina-Andriamanivo H, Porphyre V, Jambou R. Control of cysticercosis in Madagascar: beware of the pitfalls. Trends Parasitol 2013; 29:538-47. [PMID: 24145061 DOI: 10.1016/j.pt.2013.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Revised: 09/09/2013] [Accepted: 09/09/2013] [Indexed: 01/21/2023]
Abstract
Taenia solium cysticercosis is a zoonosis of public health importance in areas where the disease is endemic, with significant economic impacts on human health and the swine industry. Several gaps remain in the epidemiology of the parasite and the strategies of control in developing countries. We detail the key factors to consider in Madagascar in terms of the porcine husbandry system, Taenia transmission cycle, and diagnosis of cysticercosis in pigs, in order to better estimate the sanitary and economic impacts of this parasitic disease as well as to define an integrated control program.
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Affiliation(s)
- Harentsoaniaina Rasamoelina-Andriamanivo
- FOFIFA, Département de Recherches Zootechniques et Vétérinaires, Antananarivo, Madagascar; Département Vétérinaire, Faculté de Médecine, Antananarivo, Madagascar
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Mkupasi EM, Ngowi HA, Sikasunge CS, Leifsson PS, Johansen MV. Efficacy of ivermectin and oxfendazole against Taenia solium cysticercosis and other parasitoses in naturally infected pigs. Acta Trop 2013; 128:48-53. [PMID: 23806569 DOI: 10.1016/j.actatropica.2013.06.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 06/11/2013] [Accepted: 06/14/2013] [Indexed: 11/13/2022]
Abstract
Smallholder semi-confined pig production is a fast growing practice in sub-Saharan Africa with an unfortunate outcome of high prevalence of Taenia solium cysticercosis and other parasitoses. The widely used anthelmintic for control of endo and ecto-parasites in pigs in the area is ivermectin at a recommended dose of 0.3mg/kg. This study was conducted to evaluate the efficacy and safety in pigs after subcutaneous injection of ivermectin (IVM, 0.3mg/kg) and orally administration of oxfendazole (OFZ, 30mg/kg) in treatment of porcine cysticercosis and other parasitoses in naturally infected pigs. A total of 61 pigs with T. solium cysticercosis (38 males and 23 females) as identified by tongue palpation with age ranging from 3 to 24 months were recruited. The pigs were stratified based on sex, age and number of cysts on the tongue and randomly allocated to IVM, OFZ and control groups. Three days before treatment and two weeks after treatment faecal samples and skin scrapings were taken to establish the burden of endo- and ectoparasites, respectively and the effect of the treatment. No adverse effect was observed in any of the treatment groups throughout the study period. Half of the pigs from each group were slaughtered at week four and the remaining half at week twelve post treatment. The IVM treatment group had no significant effect (p=0.224) on T. solium cysts viability in comparison to the control group. Significant effect on cysts viability was observed in the OFZ treated group (p<0.001) compared to IVM and control groups in all muscle tissues. Regarding to brain cysts, neither of the drugs was efficacious. Ivermectin and OFZ treatments significantly reduced (p<0.001) the faecal egg count of Ascaris suum, strongyles and Trichuris suis two weeks after treatment. At slaughter, Oesophagostomum dentatum, Ascarops strongylina and Physocephalus sexalatus were recovered from pigs in the IVM treated and in the control groups. Ivermectin was 100% effective in control of Sarcoptes scabiei. In conclusion, IVM at a single dose of 0.3mg/kg was efficacious against ectoparasites but did not effectively cure pigs from T. solium cysticercosis or nematodes. Oxfendazole, on the other hand, killed all nematodes and muscle cysts, but did not have any effect on ectoparasites. A combination of the two drugs would be a most useful treatment option for control of pig parasitoses in sub-Saharan Africa.
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Affiliation(s)
- Ernatus Martin Mkupasi
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C, Denmark.
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DeWolf BD, Peregrine AS, Jones-Bitton A, Jansen JT, Menzies PI. Taenia ovisinfection and its control: a Canadian perspective. N Z Vet J 2013; 62:1-7. [DOI: 10.1080/00480169.2013.832109] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Control of Taenia solium taeniasis/cysticercosis: past practices and new possibilities. Parasitology 2013; 140:1566-77. [DOI: 10.1017/s0031182013001005] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYNeurocysticercosis continues to be a major health burden on humans living in many regions of the world, despite the availability of highly effective taeniacides and identification of the cause, Taenia solium, as being potentially eradicable. Several T. solium control trials have been undertaken, generally achieving limited success and none that has been fully documented has achieved what was demonstrated to be a sustainable level of disease control. Pigs act as intermediate hosts for T. solium and two new control tools have become available for application in pigs – single-dose oxfendazole treatment of porcine cysticercosis and the TSOL18 vaccine. Three potential intervention scenarios for pigs are compared for control of cysticercosis, using either oxfendazole or vaccination. A control scenario involving vaccination plus oxfendazole treatment delivered at 4 monthly intervals was predicted to achieve the best outcome, with no pigs slaughtered at 12 months of age having viable T. solium cysticerci. Now that new control tools are available, there are opportunities to concentrate research attention on evaluation of novel control scenarios leading to the implementation of effective and sustainable control programmes and a reduction in the global burden of neurocysticercosis.
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Mkupasi EM, Sikasunge CS, Ngowi HA, Johansen MV. Efficacy and safety of anthelmintics tested against Taenia solium cysticercosis in pigs. PLoS Negl Trop Dis 2013; 7:e2200. [PMID: 23936558 PMCID: PMC3723597 DOI: 10.1371/journal.pntd.0002200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Porcine cysticercosis, an infection caused by Taenia solium metacestodes, is continuously being reported in low-income countries of Latin America, Asia, and sub-Saharan Africa. The disease was declared eradicable by the International Task Force for Diseases Eradication (ITFDE) in 1993, and it is listed among the 17 WHO Neglected Tropical Diseases and Neglected Zoonoses that are potentially eradicable. In view of that, WHO has proposed a step-wise approach to its elimination, including chemotherapy of infected pigs. Different drugs have been tested on porcine cysticercosis with varying efficacies. These include flubendazole, fenbendazole, albendazole, albendazole sulphoxide, oxfendazole, praziquantel, and nitazoxanide. This review summarises available information on the efficacies and adverse effects shown by these drugs in pigs. Oxfendazole has shown to be effective for the control of porcine cysticercosis; however, it needs to be integrated with other control approaches. There is a need for standardised guidelines for evaluating the efficacy of anthelmintics against porcine cysticercosis, and more efficacy studies are needed since the conclusions so far are based on a limited number of studies using few infected pigs.
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Affiliation(s)
- Ernatus Martin Mkupasi
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
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Assana E, Lightowlers MW, Zoli AP, Geerts S. Taenia solium taeniosis/cysticercosis in Africa: Risk factors, epidemiology and prospects for control using vaccination. Vet Parasitol 2013; 195:14-23. [DOI: 10.1016/j.vetpar.2012.12.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 12/04/2012] [Accepted: 12/11/2012] [Indexed: 10/27/2022]
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Gilman RH, Gonzalez AE, Llanos-Zavalaga F, Tsang VCW, Garcia HH. Prevention and control of Taenia solium taeniasis/cysticercosis in Peru. Pathog Glob Health 2013; 106:312-8. [PMID: 23265557 DOI: 10.1179/2047773212y.0000000045] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Taenia solium is endemic in most of the world, causing seizures and other neurological symptoms. Transmission is mainly maintained in rural areas by a human to pig cycle. Despite claims on its eradicability, sustainable interruption of transmission has not yet been reported. This manuscript reviews the conceptual basis for control, available diagnostic and control tools, and recent experiences on control in the field performed in Peru along the past decade.
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Affiliation(s)
- Robert H Gilman
- Department of Microbiology, and Center for Global Health-Tumbes, Universidad Peruana Cayetano Heredia, Lima, Peru
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Disruption of the blood-brain barrier in pigs naturally infected with Taenia solium, untreated and after anthelmintic treatment. Exp Parasitol 2013; 134:443-6. [PMID: 23684909 DOI: 10.1016/j.exppara.2013.05.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 04/01/2013] [Accepted: 05/05/2013] [Indexed: 11/23/2022]
Abstract
Neurocysticercosis is a widely prevalent disease in the tropics that causes seizures and a variety into of neurological symptoms in most of the world. Experimental models are limited and do not allow assessment of the degree of inflammation around brain cysts. The vital dye Evans Blue (EB) was injected to 11 pigs naturally infected with Taenia solium cysts to visually identify the extent of disruption of the blood-brain barrier. A total of 369 cysts were recovered from the 11 brains and classified according to the staining of their capsules as blue or unstained. The proportion of cysts with blue capsules was significantly higher in brains from pigs that had received anthelmintic treatment 48 and 120h before the EB infusion, indicating a greater compromise of the blood-brain barrier due to treatment. The model could be useful for understanding the pathology of treatment-induced inflammation in neurocysticercosis.
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Prevalence of porcine cysticercosis and associated risk factors in Homa Bay District, Kenya. BMC Vet Res 2012; 8:234. [PMID: 23217158 PMCID: PMC3528429 DOI: 10.1186/1746-6148-8-234] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 11/27/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Taenia solium is an important zoonosis in many developing countries. Cysticercosis poses a serious public health risk and leads to economic losses to the pig production industry. Due to scarcity of data on the epidemiology of porcine cysticercosis in Kenya, the present study was conducted to determine the prevalence and risk factors for porcine cysticercosis within Homa Bay district. A cross-sectional survey was carried out in 2010, and a total of 392 pigs were recruited in a household survey, with all being tested by ante-mortem lingual palpation (together with questionnaire data on pig production, occurrence and transmission of porcine cysticercosis, risk factors and awareness of porcine cysticercosis collected from the households from which pigs were sampled). Sufficient serum was collected from 232 of the pigs to be tested for the presence of circulating parasite antigen using a monoclonal antibody-based sandwich enzyme-linked immunosorbent assay (Ag-ELISA). RESULTS Seventy six pigs were found positive by the Ag-ELISA (32.8%, 95% C.I. 26.8-39.2%), while by tongue inspection cysticerci were detected in 22/ 392 pigs (5.6% 95% C.I. 3.6-8.4%).The most important risk factor for porcine cysticercosis in the Homa Bay area was for pigs to belong to a farm where latrine use by members of the household was not evident (OR = 1.9, 95% CI = 1.13-2.37). CONCLUSION The present findings indicate that porcine cysticercosis is endemic in Homa Bay District, and that latrine provision, in conjunction with free-range pig keeping contributes significantly to porcine cysticercosis transmission.
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Iburg TM, Karlsson M, Spång F, Sikasunge CS, Johansen MV. The effect of oxfendazole treatment on muscle pathology in pigs infected with Taenia solium cysticercosis. Vet Parasitol 2012; 190:442-6. [DOI: 10.1016/j.vetpar.2012.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 07/05/2012] [Accepted: 07/09/2012] [Indexed: 11/16/2022]
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Pondja A, Neves L, Mlangwa J, Afonso S, Fafetine J, Willingham AL, Thamsborg SM, Johansen MV. Use of oxfendazole to control porcine cysticercosis in a high-endemic area of Mozambique. PLoS Negl Trop Dis 2012; 6:e1651. [PMID: 22666509 PMCID: PMC3362632 DOI: 10.1371/journal.pntd.0001651] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 04/08/2012] [Indexed: 11/18/2022] Open
Abstract
A randomized controlled field trial to evaluate the effectiveness of a single oral dose of 30 mg/kg of oxfendazole (OFZ) treatment for control of porcine cysticercosis was conducted in 4 rural villages of Angónia district, north-western Mozambique. Two hundred and sixteen piglets aged 4 months were selected and assigned randomly to OFZ treatment or control groups. Fifty-four piglets were treated at 4 months of age (T1), while another 54 piglets were treated at 9 months of age (T2) and these were matched with 108 control pigs from the same litters and raised under the same conditions. Baseline data were collected on the prevalence of porcine cysticercosis using antigen ELISA (Ag-ELISA), as well as knowledge and practices related to Taenia solium transmission based on questionnaire interviews and observations. All animals were followed and re-tested for porcine cysticercosis by Ag-ELISA at 9 and 12 months of age when the study was terminated. Overall prevalence at baseline was 5.1% with no significant difference between groups. At the end of the study, 66.7% of the controls were found positive, whereas 21.4% of the T1 and 9.1% of the T2 pigs were positive, respectively. Incidence rates of porcine cysticercosis were lower in treated pigs as compared to controls. Necropsy of 30 randomly selected animals revealed that viable cysts were present in none (0/8) of T2 pigs, 12.5% (1/8) of T1 pigs and 42.8% (6/14) of control pigs. There was a significant reduction in the risk of T. solium cysticercosis if pigs were treated with OFZ either at 4 months (OR = 0.14; 95% CI: 0.05-0.36) or at 9 months of age (OR = 0.05; 95% CI: 0.02-0.16). Strategic treatment of pigs in endemic areas should be further explored as a means to control T. solium cysticercosis/taeniosis.
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Affiliation(s)
- Alberto Pondja
- Faculty of Veterinary Medicine, Eduardo Mondlane University, Maputo, Mozambique.
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Mwape KE, Phiri IK, Praet N, Muma JB, Zulu G, Van den Bossche P, de Deken R, Speybroeck N, Dorny P, Gabriël S. Taenia solium Infections in a rural area of Eastern Zambia-a community based study. PLoS Negl Trop Dis 2012; 6:e1594. [PMID: 22479664 PMCID: PMC3313923 DOI: 10.1371/journal.pntd.0001594] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 02/24/2012] [Indexed: 11/18/2022] Open
Abstract
Background Taenia solium taeniosis/cysticercosis is a parasitic infection occurring in many developing countries. Data on the status of human infections in Zambia is largely lacking. We conducted a community-based study in Eastern Zambia to determine the prevalence of human taeniosis and cysticercosis in a rural community. Methods and Findings Stool and serum samples were collected from willing participants. Geographical references of the participants' households were determined and household questionnaires administered. Taeniosis was diagnosed in stool samples by coprology and by the polyclonal antibody-based copro-antigen enzyme-linked immunosorbent assay (copro-Ag ELISA), while cysticercosis was diagnosed in serum by the B158/B60 monoclonal antibody-based antigen ELISA (sero-Ag ELISA). Identification of the collected tapeworm after niclosamide treatment and purgation was done using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A total of 255 households from 20 villages participated in the study, 718 stool and 708 serum samples were collected and examined. Forty-five faecal samples (6.3%) were found positive for taeniosis on copro-Ag ELISA while circulating cysticercus antigen was detected in 5.8% (41/708) individuals. The tapeworm recovered from one of the cases was confirmed to be T. solium on PCR-RFLP. Seropositivity (cysticercosis) was significantly positively related to age (p = 0.00) and to copro-Ag positivity (taeniosis) (p = 0.03) but not to gender. Change point analysis revealed that the frequency of cysticercus antigens increased significantly in individuals above the age of 30. Copro-Ag positivity was not related to age or gender. The following risk factors were noted to be present in the study community: free-range pig husbandry system and poor sanitation with 47.8% of the households visited lacking latrines. Conclusions This study has recorded high taeniosis and cysticercosis prevalences and identified the need for further studies on transmission dynamics and impact of the disease on the local people. Taenia solium taeniosis/cysticercosis is a zoonotic infection endemic in many developing countries, with humans as the definitive host (taeniosis) and pigs and humans as the intermediate hosts (cysticercosis). When humans act as the intermediate host, the result can be neurocysticercosis, which is associated with acquired epilepsy, considerable morbidity and even mortality. In Africa, most studies have been carried out in pigs with little or no data in humans available. In this human study, conducted in a rural community in Eastern Zambia, prevalences for taeniosis and cysticercosis were determined at 6.3% and 5.8% respectively, indicating the hyperendemicity of the area. Cysticercosis infection was strongly related with age, with a significant increase in prevalence occurring in individuals from the age of 30 onward. A collected tapeworm was confirmed to be T. solium. Risk factors associated with the transmission and maintenance of the parasite such as free roaming pigs, households without latrines, backyard slaughter of pigs without inspection and consumption of undercooked pork were also present. The findings of this work have identified the need for further research in the transmission dynamics and the burden that this infection has on the resources of poor local people.
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Affiliation(s)
- Kabemba E. Mwape
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Isaac K. Phiri
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Nicolas Praet
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - John B. Muma
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | | | | | - Reginald de Deken
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Niko Speybroeck
- Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Pierre Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Sarah Gabriël
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
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Cysticercosis and Echinococcosis. Curr Top Microbiol Immunol 2012. [DOI: 10.1007/978-3-662-45792-4_234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
Cysticercosis and cystic echinococcosis are zoonotic parasitic diseases commonly transmitted by livestock animals. Past and future efforts to reduce transmission of these diseases adopt a One Health approach where control measures are implemented largely in the parasites' animal hosts in order to bring about, indirectly, a reduction in human disease. New and highly effective vaccines have been produced which are capable of preventing infections with Echinococcus granulosus (cystic echinococcosis) and Taenia solium (cysticercosis) in their animal intermediate hosts. Application of vaccines, together with taeniacides in the parasites' definitive hosts, provides new opportunities for control of these diseases and a reduction in the global burden of human cysticercosis and cystic echinococcosis.
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Affiliation(s)
- M W Lightowlers
- Veterinary Clinical Centre, The University of Melbourne, Werribee, Australia,
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Short Communication: In Vitro Efficacy Testing of Praziquantel, Ivermectin, and Oxfendazole against Taenia Solium Cysts. J Parasitol Res 2011; 2012:363276. [PMID: 21785697 PMCID: PMC3135050 DOI: 10.1155/2012/363276] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2011] [Accepted: 04/01/2011] [Indexed: 11/23/2022] Open
Abstract
Oxfendazole is recommended as the drug of choice for treating porcine cysticercosis. The drug does not kill brain cysts and is not registered for use in pigs. Latest its safety in the recommended dose has been questioned. The aim of this study was to investigate two alternative anthelminthics. The efficacy of praziquantel and ivermectin was compared to oxfendazole In Vitro on Taenia solium. Cysts of T. solium were isolated from infected pork and incubated in culture media together with the drugs. The degree of evagination was used as effect measurement and determined after 6 hours.
Praziquantel had a half maximal effective concentration (EC50) of value 0.006 ± 0.001 μg/mL. Ivermectin did not show any impact on the evagination in concentrations from 0.001 to 30 μg/mL and neither did oxfendazole in concentrations from 0.001 to 50 μg/mL.
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Afonso SMS, Vaz Y, Neves L, Pondja A, Dias G, Willingham AL, Vilhena M, Duarte PC, Jost CC, Noormahomed EV. Human and porcine Taenia solium infections in Mozambique: identifying research priorities. Anim Health Res Rev 2011; 12:123-9. [PMID: 21676344 PMCID: PMC6384509 DOI: 10.1017/s1466252311000077] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The objective of this paper is to critically review and summarize available scientific and lay literature, and ongoing studies on human and porcine cysticercosis in Mozambique to identify knowledge gaps and direct immediate and long-term research efforts. Data on the spatial distribution and prevalence of the disease in human and swine populations are scarce and fragmented. Human serological studies have shown that 15-21% of apparently healthy adults were positive for cysticercosis antibodies or antigen, while in neuropsychiatric patients seroprevalence was as high as 51%. Slaughterhouse records indicate a countrywide occurrence of porcine cysticercosis, while studies have shown that 10-35% of pigs tested were seropositive for cysticercosis antibodies or antigen. Current research in Mozambique includes studies on the epidemiology, molecular biology, diagnosis and control of the disease. Future research efforts should be directed at better understanding the epidemiology of the disease in Mozambique, particularly risk factors for its occurrence and spread in human and swine populations, documenting the socio-economic impact of the disease, identifying critical control points and evaluating the feasibility and epidemiological impact of control measures and development of local level diagnostic tools for use in humans and swine.
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Affiliation(s)
- S. M. S. Afonso
- Veterinary Faculty, Eduardo Mondlane University, Av. de Moçambique 1,5 Km, Maputo, Mozambique
| | - Y. Vaz
- Faculty of Veterinary Medicine, Technical University of Lisbon – TULisbon, Av. da Universidade, Técnica 1300-477, Lisbon, Portugal
| | - L. Neves
- Biotechnology Centre, Eduardo Mondlane University, Av. de Moçambique 1,5 Km, Maputo, Mozambique
| | - A. Pondja
- Veterinary Faculty, Eduardo Mondlane University, Av. de Moçambique 1,5 Km, Maputo, Mozambique
| | - G. Dias
- Veterinary Faculty, Eduardo Mondlane University, Av. de Moçambique 1,5 Km, Maputo, Mozambique
| | - A. L. Willingham
- WHO/FAO Collaborating Centre for Research and Training on Neglected and Other Parasitic Zoonoses, Section for Parasitology, Health and Development, Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Dyrlaegevej 100, Frederiksberg C 1870, Denmark
| | - M. Vilhena
- Department of Veterinary Medicine, University of Évora, Pólo da Mitra Ap. 94, 7002-554, Portugal
| | - P. C. Duarte
- Secretariat of International Affairs (SRI), Brazilian Agricultural Research Corporation (EMBRAPA), Ministry of Agriculture, Livestock and Food Supply (MAPA), PqEB, Av. W3 Norte (Final) – Edifício Sede, 70770-901 Brasília-DF, Brasil
- International Livestock Research Institute, P.O. Box 30709, Nairobi 00100, Kenya
| | - C. C. Jost
- International Livestock Research Institute, P.O. Box 30709, Nairobi 00100, Kenya
| | - E. V. Noormahomed
- Medical Faculty, Eduardo Mondlane University, Av. Salvador Allende 702, Maputo, Mozambique
- School of Medicine, University of California San Diego, 9500 Gilman Drive, MC 0602, La Jolla, CA 92093-0602, USA
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