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Kabululu ML, Johansen MV, Lightowlers M, Trevisan C, Braae UC, Ngowi HA. Aggregation of Taenia solium cysticerci in pigs: Implications for transmission and control. Parasite Epidemiol Control 2023; 22:e00307. [PMID: 37261135 PMCID: PMC10227459 DOI: 10.1016/j.parepi.2023.e00307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 04/02/2023] [Accepted: 05/19/2023] [Indexed: 06/02/2023] Open
Abstract
Parasite aggregation within hosts is a fundamental feature of parasite distributions, whereby the majority of parasites are harboured by a minority of hosts. Parasite aggregation can influence their transmission and hence control. In this narrative review, possible sources of aggregation of Taenia solium cysticerci in pigs are discussed, along with implications for control of the parasite. While heavy T. solium infections in pigs could most likely be associated with ingestion of high doses of infective parasite eggs, consistent with coprophagic behaviour of pigs, lighter infections indicate a role of indirect routes of transmission to pigs, mostly from lower infection doses. Light infections are likely to be missed by commonly used diagnostic methods - tongue examination or meat inspection - and end up in the food chain. Hence, they entail a 'hidden' risk and are of a particular public health concern, especially in areas where meat is consumed raw or undercooked. To be effective and sustainable, control strategies against T. solium likely require a broader understanding of, and consideration for parasite transmission dynamics. More importantly, a holistic One Health approach incorporating interventions on humans, pigs and the environment will likely have a larger, more successful and sustainable impact.
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Affiliation(s)
| | | | - Marshall Lightowlers
- Department of Biosciences, Melbourne Veterinary School, University of Melbourne, Werribee, Victoria, Australia
| | - Chiara Trevisan
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Translational Physiology, Infectiology and Public Health, Faculty of Veterinary Medicine, Ghent University, Belgium
| | - Uffe C. Braae
- One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
| | - 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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Makingi G, Ngowi B, Mkupasi E, Wilson C, Winkler AS, Nzalawahe J, Ngowi H. Community Health-Education Intervention Trial against Human Taenia solium Taeniasis/Cysticercosis in Central and Southern Zones of Tanzania. Pathogens 2023; 12:955. [PMID: 37513802 PMCID: PMC10386120 DOI: 10.3390/pathogens12070955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 04/18/2023] [Accepted: 06/09/2023] [Indexed: 07/30/2023] Open
Abstract
Poor knowledge of human T. solium taeniasis/cysticercosis and insufficient sanitary and hygienic practices have been associated with the persistence of human T. solium infections in endemic areas. Community health education intervention measures were implemented in 42 villages of Kongwa and Songwe Districts to increase knowledge, improve good practices against infection and reduce incidences of human cysticercosis transmission using a health education package. The health education package comprised of leaflet, poster and a booklet The 42 villages were allocated into intervention group and control group, and each group consisted of 21 villages. Baseline and post-intervention information on social demography, knowledge, safe practices and incidences of human cysticercosis was collected from both village groups. The impact of the intervention was evaluated by comparing changes in knowledge, preventive practices related to human T. solium infections and the cumulative incidence of human cysticercosis between intervention and control villages. There was no significant difference in mean knowledge scores and preventive practice mean scores between the control and intervention groups at baseline. However, there were significantly higher knowledge mean scores in the intervention group compared to the control group at one year post-intervention (2.06 ± 1.45 vs. 0.94 ± 1.18, p < 0.001). There was no significant difference in the mean practice scores between the intervention and the control group at one year post-intervention (2.49 ± 1.13 vs. 2.40 ± 1.13, p = 0.31). Furthermore, there was no significant difference in the prevalence of human T. solium cysticercosis between the intervention and the control group at the baseline (1.4% vs. 1.4%, p = 0.97) by Ag-Elisa, and at one year post-intervention the cumulative incidence of human cysticercosis was 1.9 and 1.2 per cent in the control and intervention group, respectively. There was no significant difference in the cumulative incidence of human cysticercosis between the intervention and the control group at one year post-intervention (p > 0.05). Community health-education intervention is effective at improving the knowledge of human T. solium infections. The improvement in preventive practices and reduction in incidences of human cysticercosis are a gradual process, they may require sanitary and hygienic improvement and more time after the intervention to see improved changes. The study recommends a sustainable public health education on T. solium infections using the health education package through one health approach.
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Affiliation(s)
- George Makingi
- The College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3021, Tanzania
| | - Bernard Ngowi
- Muhimbili Medical Research Centre, National Institute for Medical Research, Dar es Salaam P.O. Box 3436, Tanzania
- Mbeya College of Health and Allied Sciences, University of Dar es Salaam, Mbeya P.O. Box 608, Tanzania
| | - Ernatus Mkupasi
- The College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3021, Tanzania
| | - Christina Wilson
- The College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3021, Tanzania
| | - Andrea Sylvia Winkler
- Center for Global Health, Department of Neurology, Technical University of Munich, 81675 Munich, Germany
- Department of Community Medicine and Global Health, Institute of Health and Society, University of Oslo, 0373 Oslo, Norway
| | - Jahashi Nzalawahe
- The College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3021, Tanzania
| | - Helena Ngowi
- The College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro P.O. Box 3021, Tanzania
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Zulu G, Stelzle D, Mwape KE, Welte TM, Strømme H, Mubanga C, Mutale W, Abraham A, Hachangu A, Schmidt V, Sikasunge CS, Phiri IK, Winkler AS. The epidemiology of human Taenia solium infections: A systematic review of the distribution in Eastern and Southern Africa. PLoS Negl Trop Dis 2023; 17:e0011042. [PMID: 37000841 PMCID: PMC10096517 DOI: 10.1371/journal.pntd.0011042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 04/12/2023] [Accepted: 03/12/2023] [Indexed: 04/03/2023] Open
Abstract
Background
Taenia solium is a tapeworm that causes taeniosis in humans and cysticercosis in humans and pigs. Within Eastern and Southern Africa (ESA), information on the presence of human taeniosis and cysticercosis seems scarce. This systematic review aimed to describe the current information available and gaps in the epidemiology of human T. solium infections in ESA.
Methods/Principle findings
Scientific literature published between 1st January 2000 and 20th June 2022 in international databases [MEDLINE (Ovid), Embase (Ovid), Global Health (Ovid), Scopus (Elsevier), African Index Medicus (via WHO Global Index Medicus), and Open Grey] was systematically reviewed for ESA. The study area included 27 countries that make up the ESA region. Information on either taeniosis, cysticercosis or NCC was available for 16 of 27 countries within the region and a total of 113 reports were retained for the review. Most case reports for cysticercosis and NCC were from South Africa, while Tanzania had the most aggregated cysticercosis reports. Eleven countries reported on NCC with seven countries reporting data on NCC and epilepsy. Unconfirmed human T. solium taeniosis cases were reported in nine countries while two countries (Madagascar and Zambia) reported confirmed T. solium cases. The cysticercosis seroprevalence ranged between 0.7–40.8% on antigen (Ag) ELISA and between 13.1–45.3% on antibody (Ab) ELISA. Based on immunoblot tests the Ab seroprevalence was between 1.7–39.3%, while the proportion of NCC-suggestive lesions on brain CT scans was between 1.0–76% depending on the study population. The human taeniosis prevalence based on microscopy ranged between 0.1–14.7%. Based on Copro Ag-ELISA studies conducted in Kenya, Rwanda, Tanzania, and Zambia, the highest prevalence of 19.7% was reported in Kenya.
Conclusions
Despite the public health and economic impact of T. solium in ESA, there are still large gaps in knowledge about the occurrence of the parasite, and the resulting One Health disease complex, and monitoring of T. solium taeniosis and cysticercosis is mostly not in place.
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Wang Z, Garcia RM, Huff HV, Niquen-Jimenez M, Marcos LA, Lam SK. Neurocysticercosis control for primary epilepsy prevention: a systematic review. Pathog Glob Health 2022; 116:282-296. [PMID: 34928183 PMCID: PMC9248947 DOI: 10.1080/20477724.2021.2015869] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Neurocysticercosis (NCC) is a leading cause of preventable epilepsy in lower- and upper- middle-income countries (LMICs/UMICs). NCC is a human-to-human transmitted disease caused by ingestion of Taenia solium eggs from a Taenia carrier. T. solium infection control is the key to reduce NCC incidence. This systematic review aims to identify T. solium control programs that can provide frameworks for endemic areas to prevent NCC-related epilepsy. A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Cochrane Library databases in March 2021. After title and abstract review, full texts were screened for qualitative analysis. Additional articles were identified via citation search. Of 1322 total results, 34 unique studies were included. Six major intervention types were identified: national policy (8.8%), community sanitation improvement (8.8%), health education (8.8%), mass drug administration (29.4%), pig vaccination and treatment (32.4%), and combined human and pig treatment (11.8%). Overall, 28 (82.4%) studies reported decreased cysticercosis prevalence following the intervention. Only health education and combined human and pig treatment were effective in all selected studies. NCC causes preventable epilepsy in LMICs/UMICs and its incidence can be reduced through T. solium control. Most interventions that disrupt the T. solium transmission cycle are effective. Long-term sustained results require comprehensive programs, ongoing surveillance, and collaborative effort among multisectoral agencies.
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Affiliation(s)
- Zhe Wang
- Department of Neurological Surgery, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA,Division of Infectious Diseases, Department of Medicine, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA,Department of Microbiology and Immunology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA,CONTACT Zhe Wang Department of Neurological Surgery, Stony Brook University Renaissance School of Medicine, HSC T12 Rm 080, 100 Nicolls Rd, Stony Brook, NY11790, USA
| | - Roxanna M. Garcia
- Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Hanalise V. Huff
- Fogarty Fellow, Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Milagros Niquen-Jimenez
- Facultad de Medicina Humana Alberto Hurtado, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Luis A. Marcos
- Division of Infectious Diseases, Department of Medicine, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA,Department of Microbiology and Immunology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | - Sandi K. Lam
- Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA,Division of Pediatric Neurosurgery, Ann & Robert H. Lurie Children’s Hospital, Chicago, IL, USA
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Ngwili N, Thomas L, Githigia S, Johnson N, Wahome R, Roesel K. Stakeholders' Knowledge, Attitude, and Perceptions on the Control of Taenia solium in Kamuli and Hoima Districts, Uganda. Front Vet Sci 2022; 9:833721. [PMID: 35464359 PMCID: PMC9021822 DOI: 10.3389/fvets.2022.833721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 03/07/2022] [Indexed: 11/18/2022] Open
Abstract
Taenia (T.) solium is a zoonotic parasite causing three diseases: Taeniasis and cysticercosis in humans and porcine cysticercosis in pigs. Although biomedically, the transmission of the parasite can be easily interrupted at six points along the life cycle, the contextual factors that may influence the adoption of these control strategies in Uganda remain unclear. This study assessed the stakeholders' knowledge, attitudes, and perceptions relating to the six control strategies for T. solium infections in Kamuli and Hoima districts, Uganda. A total of 22 focus group discussions (FGD) were conducted with pig farmers, community leaders, pig/pork traders, animal health assistants, and human health assistants. In addition, nine key informant interviews were held with senior officials in the ministries of agriculture and health and other relevant agencies at the district level. The results showed differential, limited, and fragmented knowledge on T. solium infections among stakeholders. Pig farmers, community leaders, and pig/pork traders had almost no knowledge and were often confused regarding the differences existing between T. solium and other gastro-intestinal infections in pigs and humans. Pig confinement, pit latrine construction, coverage, maintenance, and sustained use are influenced by cultural, socio-economic, and physical/ environmental factors of the study population and area. Proper sensitisation programmes and health education interventions should target all, but with appropriately focused material to suit the different stakeholder categories. Reminders or nudges may be needed to ensure that increase in knowledge translates to changes in practise. Intervention programmes should also aim to overcome challenges created by the various contextual factors operating in the specific endemic areas.
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Affiliation(s)
- Nicholas Ngwili
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- Faculty of Veterinary Medicine, University of Nairobi, Nairobi, Kenya
- *Correspondence: Nicholas Ngwili ; orcid.org/0000-0002-3940-4438
| | - Lian Thomas
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, United Kingdom
| | - Samuel Githigia
- Faculty of Veterinary Medicine, University of Nairobi, Nairobi, Kenya
| | - Nancy Johnson
- International Food Policy Research Institute IFPRI, Washington, DC, United States
| | - Raphael Wahome
- Faculty of Veterinary Medicine, University of Nairobi, Nairobi, Kenya
| | - Kristina Roesel
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- Department of Veterinary Medicine, Institute of Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
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Ngwili N, Johnson N, Wahome R, Githigia S, Roesel K, Thomas L. A qualitative assessment of the context and enabling environment for the control of Taenia solium infections in endemic settings. PLoS Negl Trop Dis 2021; 15:e0009470. [PMID: 34115758 PMCID: PMC8221787 DOI: 10.1371/journal.pntd.0009470] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 06/23/2021] [Accepted: 05/12/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Taenia solium (T. solium), is a zoonotic helminth causing three diseases namely; taeniasis (in humans), neurocysticercosis (NCC, in humans) and porcine cysticercosis (PCC, in pigs) and is one of the major foodborne diseases by burden. The success or failure of control options against this parasite in terms of reduced prevalence or incidence of the diseases may be attributed to the contextual factors which underpin the design, implementation, and evaluation of control programmes. METHODOLOGY/PRINCIPAL FINDINGS The study used a mixed method approach combining systematic literature review (SLR) and key informant interviews (KII). The SLR focused on studies which implemented T. solium control programmes and was used to identify the contextual factors and enabling environment relevant to successful inception, planning and implementation of the interventions. The SLR used a protocol pre-registered at the International prospective register of systematic reviews (PROSPERO) number CRD42019138107 and followed PRISMA guidelines on reporting of SLR. To further highlight the importance and interlinkage of these contextual factors, KII were conducted with researchers/implementers of the studies included in the SLR. The SLR identified 41 publications that had considerations of the contextual factors. They were grouped into efficacy (10), effectiveness (28) and scale up or implementation (3) research studies. The identified contextual factors included epidemiological, socioeconomic, cultural, geographical and environmental, service and organizational, historical and financial factors. The enabling environment was mainly defined by policy and strategies supporting T. solium control. CONCLUSION/SIGNIFICANCE Failure to consider the contextual factors operating in target study sites was shown to later present challenges in project implementation and evaluation that negatively affected expected outcomes. This study highlights the importance of fully considering the various domains of the context and integrating these explicitly into the plan for implementation and evaluation of control programmes. Explicit reporting of these aspects in the resultant publication is also important to guide future work. The contextual factors highlighted in this study may be useful to guide future research and scale up of disease control programmes and demonstrates the importance of close multi-sectoral collaboration in a One Health approach.
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Affiliation(s)
- Nicholas Ngwili
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- College of Agriculture and Veterinary Sciences, University of Nairobi, Nairobi, Kenya
| | - Nancy Johnson
- CGIAR Research program on Agriculture for Nutrition and Health, IFPRI, Washington, DC, United States of America
| | - Raphael Wahome
- College of Agriculture and Veterinary Sciences, University of Nairobi, Nairobi, Kenya
| | - Samuel Githigia
- College of Agriculture and Veterinary Sciences, University of Nairobi, Nairobi, Kenya
| | - Kristina Roesel
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Lian Thomas
- Animal and Human Health Program, International Livestock Research Institute, Nairobi, Kenya
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Lea Hurst Campus, Neston, United Kingdom
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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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Molia S, Saillard J, Dellagi K, Cliquet F, Bart JM, Rotureau B, Giraudoux P, Jannin J, Debré P, Solano P. Practices in research, surveillance and control of neglected tropical diseases by One Health approaches: A survey targeting scientists from French-speaking countries. PLoS Negl Trop Dis 2021; 15:e0009246. [PMID: 33661894 PMCID: PMC7963066 DOI: 10.1371/journal.pntd.0009246] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 03/16/2021] [Accepted: 02/16/2021] [Indexed: 12/24/2022] Open
Abstract
One health (OH) approaches have increasingly been used in the last decade in the fight against zoonotic neglected tropical diseases (NTDs). However, descriptions of such collaborations between the human, animal and environmental health sectors are still limited for French-speaking tropical countries. The objective of the current survey was to explore the diversity of OH experiences applied to research, surveillance and control of NTDs by scientists from French-speaking countries, and discuss their constraints and benefits. Six zoonotic NTDs were targeted: echinococcoses, trypanosomiases, leishmaniases, rabies, Taenia solium cysticercosis and leptospiroses. Invitations to fill in an online questionnaire were sent to members of francophone networks on NTDs and other tropical diseases. Results from the questionnaire were discussed during an international workshop in October 2019. The vast majority (98%) of the 171 respondents considered OH approaches relevant although only 64% had implemented them. Among respondents with OH experience, 58% had encountered difficulties mainly related to a lack of knowledge, interest and support for OH approaches by funding agencies, policy-makers, communities and researchers. Silos between disciplines and health sectors were still strong at both scientific and operational levels. Benefits were reported by 94% of respondents with OH experience, including increased intellectual stimulation, stronger collaborations, higher impact and cost-efficiency of interventions. Recommendations for OH uptake included advocacy, capacity-building, dedicated funding, and higher communities' involvement. Improved research coordination by NTD networks, production of combined human-animal health NTD impact indicators, and transversal research projects on diagnostic and reservoirs were also considered essential.
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Affiliation(s)
- Sophie Molia
- CIRAD, UMR ASTRE, Montpellier, France
- ASTRE, Univ Montpellier, CIRAD, INRAE, Montpellier, France
| | | | - Koussai Dellagi
- Institut Pasteur International Network, Institut Pasteur, Paris, France
| | - Florence Cliquet
- ANSES, Nancy Laboratory for Rabies and Wildlife, Malzéville, France
| | | | - Brice Rotureau
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, Department of Parasites and Insect Vectors and INSERM U1201, Institut Pasteur, Paris, France
| | - Patrick Giraudoux
- Chrono-environnement Université de Bourgogne Franche-Comté/CNRS, Besançon, France
| | - Jean Jannin
- Société de Pathologie Exotique, Paris, France
| | | | - Philippe Solano
- INTERTRYP, IRD, CIRAD, Univ Montpellier, Montpellier, France
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Shongwe NA, Byaruhanga C, Dorny P, Dermauw V, Qekwana DN. Knowledge, practices and seroprevalence of Taenia species in smallholder farms in Gauteng, South Africa. PLoS One 2020; 15:e0244055. [PMID: 33338060 PMCID: PMC7748137 DOI: 10.1371/journal.pone.0244055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 12/02/2020] [Indexed: 02/01/2023] Open
Abstract
Porcine cysticercosis and associated human infections are endemic in Sub-Saharan Africa, Latin America, and Asia. Poor agricultural practices, sanitary practices, and lack of knowledge increase the burden of the diseases in susceptible populations. This study investigates the seroprevalence of Taenia spp. in township pigs in Gauteng, South Africa and describes knowledge and farming practices of pig farmers regarding T. solium infections. Blood samples were collected from 126 pigs in three Gauteng township areas, and analyzed for active Taenia spp. infection using the B158/B60 Ag-ELISA. Farmer questionnaire surveys were conducted in four township areas to investigate the level of knowledge and practices associated with porcine cysticercosis and neurocysticercosis. Logistic regression models were used to assess the relationship between predictor variables and the outcome variable, knowledge of porcine cysticercosis or knowledge of neurocysticercosis. Overall, 7% of the pigs were seropositive for active Taenia spp. infection. 46% of farmers practiced a free-ranging system, while 25% practiced a semi-intensive system. Latrines were absent on all farms; however, 95% of farmers indicated that they have access to latrines at home. Most farmers had no knowledge of porcine cysticercosis (55%) or neurocysticercosis (79%), and this was not associated with any of the factors investigated. The prevalence of active Taenia spp. infection was reasonably low in this study, yet the knowledge level was also low, thus calling for further educational and training programmes to prevent Taenia spp. transmission in these communities.
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Affiliation(s)
- Nothando Altrecia Shongwe
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, South Africa
| | - Charles Byaruhanga
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, South Africa
| | - Pierre Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Veronique Dermauw
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Daniel Nenene Qekwana
- Section of Veterinary Public Health, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
- * E-mail:
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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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11
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Kabululu ML, Ngowi HA, Mlangwa JED, Mkupasi EM, Braae UC, Trevisan C, Colston A, Cordel C, Johansen MV. Endemicity of Taenia solium cysticercosis in pigs from Mbeya Rural and Mbozi districts, Tanzania. BMC Vet Res 2020; 16:325. [PMID: 32883326 PMCID: PMC7470673 DOI: 10.1186/s12917-020-02543-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/25/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Taenia solium taeniasis/cysticercosis is a disease of substantial economic and public health importance particularly in low-income countries. The disease was reported to be endemic in Mbeya Rural and Mbozi districts, in the southern highlands of Tanzania, the major pig production area in the country. In 2008, using B158/B60 antigen detection enzyme-linked immunosorbent assay (Ag-ELISA), porcine cysticercosis prevalence of up to 32% was reported in the districts. A number of interventions have been implemented in selected villages including an integrated approach consisting of improving pig confinement and selective treatment of pigs with oxfendazole. Mass drug administration with praziquantel targeting schistosomiasis, with an expected effect on T. solium, was also provided to school-age children in the area. This study aimed at providing an update on prevalence and intensities of porcine cysticercosis; and assessing farmers' knowledge, attitudes and practices which could be associated to disease transmission in the area. The study involved a questionnaire survey conducted using face-to-face household interviews with 890 consenting farmers; and carcass dissections performed on 282 pigs randomly selected from the surveyed households. RESULTS Twenty-six pigs (9.2%) were infected with T. solium; of which two-thirds (65.4%) had light to moderate infection intensities (1-1000 cysticerci), and one-third (34.6%) had heavy intensities (> 1000 cysticerci). Questionnaire results showed that only 5.7% of the respondents perceived T. solium cysticercosis to be an important disease in pigs. About 18.5% of the respondents were aware of T. solium taeniasis, but 32% of them were unaware of how the infection is acquired. Half of the respondents had seen cysticerci in pork, of whom 61% were not aware that consumption of infected pork could cause taeniasis. Latrines were observed to often (90%) lack doors with 45% considered accessible to pigs. CONCLUSIONS This study provided an evidence that the disease was still endemic in the area. Poor knowledge of farmers, attitudes, and risky practices responsible for disease perpetuation were also revealed. A One Health approach targeting the whole area incorporating improvement of farmer knowledge regarding disease transmission needs to be trialed as a feasible approach to control.
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Affiliation(s)
- Mwemezi L Kabululu
- Tanzania Livestock Research Institute (TALIRI) - Uyole, Mbeya, Tanzania.
| | - 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
| | - 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
| | - Maria V Johansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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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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13
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Haby MM, Sosa Leon LA, Luciañez A, Nicholls RS, Reveiz L, Donadeu M. Systematic review of the effectiveness of selected drugs for preventive chemotherapy for Taenia solium taeniasis. PLoS Negl Trop Dis 2020; 14:e0007873. [PMID: 31945055 PMCID: PMC6964831 DOI: 10.1371/journal.pntd.0007873] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/25/2019] [Indexed: 01/21/2023] Open
Abstract
Background Preventive chemotherapy is a useful tool for the control of Taenia solium taeniasis and cysticercosis. The aim of this systematic review is to assess the scientific evidence concerning the effectiveness and safety of different drugs in preventive chemotherapy for T. solium taeniasis in endemic populations. Methods A systematic review was conducted of controlled and uncontrolled studies, assessing the efficacy and adverse effects (among other outcomes) of albendazole, niclosamide and/or praziquantel for preventive chemotherapy of T. solium taeniasis. A comprehensive search was conducted for published and unpublished studies. Two reviewers screened articles, completed the data extraction and assessment of risk of bias. A meta-analysis of cure rate and relative reduction in prevalence was performed. The protocol for this review was registered on the International prospective register of systematic reviews (PROSPERO), number CRD42018112533. Results We identified 3555 records, of which we included 20 primary studies reported across 33 articles. Meta-analyses of drug and dose showed that a single dose of praziquantel 10mg/kg, albendazole 400mg per day for three consecutive days, or niclosamide 2g, resulted in better cure rates for T. solium taeniasis (99.5%, 96.4% and 84.3%, respectively) than praziquantel 5mg/kg or single dose albendazole 400mg (89.0% and 52.0%, respectively). These findings have a low certainty of evidence due to high risk of bias in individual studies and heterogeneity in combined estimates. In relation to side-effects, most studies reported either no or only mild and transient side-effects within the first three days following drug administration for all drugs and doses. Conclusion Evidence indicated that praziquantel 10mg/kg, niclosamide 2g, and triple dose albendazole 400mg were effective as taenicides and could be considered for use in mass drug administration programs for the control of T. solium taeniasis. Evidence was not found that any of these drugs caused severe side effects at the indicated doses, although the extent of the available evidence was limited. Taeniasis and cysticercosis caused by Taenia solium are considered, by the WHO, to be neglected tropical diseases. Preventive chemotherapy for taeniasis in endemic populations is a useful tool for control of the parasite. Preventive chemotherapy can be implemented by treating the whole population in endemic areas at regular intervals (known as mass drug administration). While different drugs, doses and regimes have been used there were still uncertainties about which drugs and dose have the best efficacy while considering adverse effects. We conducted a systematic review of the best available literature to inform a WHO guideline for preventive chemotherapy. We found that praziquantel 10mg/kg, niclosamide 2g, and triple dose albendazole 400mg (400mg per day for three consecutive days) are all effective. Proven side-effects were mild and short-lived, when they did occur.
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Affiliation(s)
- Michelle M. Haby
- Department of Chemical and Biological Sciences, University of Sonora, Hermosillo, Sonora, Mexico
- Centre for Health Policy, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
- * E-mail:
| | | | - Ana Luciañez
- Neglected Infectious Diseases, Communicable Diseases and Environmental Determinants of Health, Pan American Health Organization/World Health Organization, Washington DC, United States of America
| | - Ruben Santiago Nicholls
- Neglected Infectious Diseases, Communicable Diseases and Environmental Determinants of Health, Pan American Health Organization/World Health Organization, Washington DC, United States of America
| | - Ludovic Reveiz
- Department of Evidence and Intelligence for Action in Health, Pan American Health Organization/World Health Organization, Washington DC, United States of America
| | - Meritxell Donadeu
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Melbourne, Victoria, Australia
- Initiative for Neglected Animal Diseases (INAND), Midrand, South Africa
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14
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Ngowi HA, Winkler AS, Braae UC, Mdegela RH, Mkupasi EM, Kabululu ML, Lekule FP, Johansen MV. Taenia solium taeniosis and cysticercosis literature in Tanzania provides research evidence justification for control: A systematic scoping review. PLoS One 2019; 14:e0217420. [PMID: 31166983 PMCID: PMC6550401 DOI: 10.1371/journal.pone.0217420] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 05/11/2019] [Indexed: 11/19/2022] Open
Abstract
Background Despite Taenia solium taeniosis/cysticercosis (TSTC) having been put high on the global agenda of neglected tropical diseases (NTDs), which over the last years has received a lot of attention, there has been no control programmes in place in sub-Saharan Africa, a highly endemic region. This could be attributed to lack of awareness of many stakeholders on the burden and impact of T. solium. This information is essential in guiding TSTC policies, practices and research agendas as well as encouraging cross-sectoral collaboration in the control of this important zoonotic parasite using a One Health approach. National elimination of the parasite is the foundation for global eradication. This will require that substantial country-level information is provided to all key stakeholders. We have mapped out TSTC research evidence in Tanzania to inform on disease burden and potential for integrated control measures. Methodology/Principal findings A scoping review of all TSTC studies undertaken in Tanzania and published up to December 2018 was conducted. The articles were searched from PUBMED, AJOL, Google Scholar and Google in general. Fifty-one (51) articles met the inclusion criteria and were reviewed. Prevalence of taeniosis of 2.3% - 5.2% was estimated based on copro-antigen ELISA while human cysticercosis of >16% was estimated based on serum antigen ELISA (Ag-ELISA) or IgG Western Blot. Neurocysticercosis (NCC) contributed significantly to epilepsy in adults. Farm prevalence of porcine cysticercosis were 6.0% - 17.4% (lingual examination) and 1.5% - 33.3% (Ag-ELISA). Slaughter-slab prevalence were 0% - 18.2% (routine meat inspection). Lacking latrines, watering pigs with river or pond water, and feeding pigs with potato peels were associated with porcine cysticercosis prevalence. Washing hands by dipping method increased the risk of human cysticercosis. In 2012, the number of DALYs/1000 person-years for NCC-associated epilepsy was 0.7 (95% UI, 0.2–1.6), around 5 million USD (95% UI, 797,535–16,933,477) were spent due to NCC-associated epilepsy and nearly 3 million USD (95% UI, 1,095,960–5,366,038) were potentially lost due to porcine cysticercosis. Three rounds of annual treatment of school-age children with praziquantel significantly reduced prevalence of taeniosis and porcine cysticercosis. Health education was efficacious in improving knowledge and attitudes favourable for control of TSTC while a single dose of oxfendazole 30 mg/kg body weight was efficacious in eliminating T. solium cysticerci from pig musculature. Conclusions/Significance The observed high burden of TSTC and the significant contribution of NCC to epilepsy in Tanzania warrant urgent interventions. Evaluation of best control options should make use of disease transmission dynamics models such as cystiSim, taking into account findings from the field based intervention studies. In addition, locally adapted management guidelines for people suffering from NCC are urgently needed.
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Affiliation(s)
- Helena Aminiel Ngowi
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
- * E-mail:
| | - Andrea Sylvia Winkler
- Center for Global Health, Department of Neurology, Technical University of Munich, Munich, Germany
- Centre for Global Health, Department of Community Medicine and Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Uffe Christian Braae
- One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
- Department of Infectious Disease Epidemiology and Prevention, Statens Serum Institut, Copenhagen, Denmark
| | | | - Ernatus Martin Mkupasi
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
| | | | - Faustin Peter Lekule
- Department of Animal Science and Production, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Maria Vang Johansen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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15
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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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16
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Overview of Taenia solium cysticercosis in West Africa. Acta Trop 2019; 190:329-338. [PMID: 30529447 DOI: 10.1016/j.actatropica.2018.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/06/2018] [Accepted: 12/06/2018] [Indexed: 12/15/2022]
Abstract
Human and porcine cysticercosis is endemic in West Africa, where epilepsy is relatively common, but rarely reported due to fear of stigmatization. Neurocysticercosis, caused by Taenia solium, tends to affect the poor in developing countries and control is hampered by inadequate infrastructure and financial resources coupled with lack of adequate information about its significance and distribution. The risk factors for human cysticercosis are closely associated with the characteristics of smallholder or backyard pig farming systems prevalent in this region. Poverty, ignorance and lack of political will militate against successful eradication, while tools for effective diagnosis, prevention and treatment, including vaccines for pigs, are not yet available in many countries. Cysticercosis was targeted for control by The World Health Organization global plan for 2008-2015; however, measures for control are yet to be undertaken in a coordinated manner in West Africa. Diagnostic tools, including neuroimaging facilities, should be strategically situated and made accessible to rural populations in West Africa. Community education in combination with a multipronged approach consisting of vaccination of pigs using TSOL18 vaccine and treatment with oxfendazole along with mass chemotherapy of humans with praziquantel could eliminate taeniasis and should be considered. In-depth and extensive epidemiological studies are required in West Africa in order to fully elucidate the prevalence of T. solium and to support more coordinated and effective control of human and porcine cysticercosis.
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Spinicci M, Macchioni F, Gabrielli S, Rojo D, Gamboa H, Villagrán AL, Vallejos Y, Strohmeyer M, Roselli M, Cancrini G, Olliaro P, Montresor A, Bartoloni A. Hymenolepis nana-An Emerging Intestinal Parasite Associated with Anemia in School Children from the Bolivian Chaco. Am J Trop Med Hyg 2018; 99:1598-1601. [PMID: 30298806 PMCID: PMC6283498 DOI: 10.4269/ajtmh.18-0397] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/21/2018] [Indexed: 12/13/2022] Open
Abstract
Tropical anemia can have multiple causes, whether socioeconomic, dietary, or infectious. In the Bolivian Chaco, soil-transmitted helminthiases (STH), malaria, and Chagas disease are potential infectious causes of anemia among school-aged children (SAC). Following years of preventive chemotherapy with mebendazole, the prevalence of STH among SAC living in that area is now negligible, whereas protozoan infections are still highly prevalent (81%); Hymenolepis nana is the most frequent intestinal helminth (∼13%). We present results of hemoglobin (Hb) assessment and the association between parasitic infections and Hb levels of that SAC population. Overall, 511 SAC (girls:boys ratio 1:1, mean age 9.4 years [95% confidence interval {CI}: 9.3-9.5]) had Hb levels measured by using a point of care testing (HemoCue® Hb 301 System; HemoCue, Angelhome, Sweden). The prevalence of anemia was 23% (117/511), with mean and median Hb level = 12.2 g/dL (95% CI: 12.1-12.3; range 9.2-15.4 g/dL). By multivariate analysis, H. nana infection was associated with an increased risk of anemia (odds ratio 2.9, 95% CI: 1.5-5.7, P = 0.002). Two samples (0.5%) were positive for Trypanosoma cruzi and none for Plasmodium spp. by polymerase chain reaction of the 439 children tested. Anemia is still a concern among SAC living in the Bolivian Chaco. Our findings call for a greater attention to fecal-oral emerging pathogens, such as H. nana, and highlight the importance of water, sanitation, and hygiene improvements for disadvantaged population such as those living in the Bolivian Chaco.
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Affiliation(s)
- Michele Spinicci
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Fabio Macchioni
- Dipartimento di Scienze Veterinarie, Università degli Studi di Pisa, Pisa, Italy
| | - Simona Gabrielli
- Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma Sapienza, Roma, Italy
| | - David Rojo
- Escuela de Salud del Chaco Tekove Katu, Gutierrez, Plurinational State of Bolivia
| | - Herlan Gamboa
- Facultad Integral del Chaco, Universidad Autónoma Gabriel René Moreno, Camiri, Plurinational State of Bolivia
| | - Ana Liz Villagrán
- Hospital Básico de Villa Montes, Villa Montes, Plurinational State of Bolivia
| | - Yolanda Vallejos
- Hospital Municipal de Camiri, Camiri, Plurinational State of Bolivia
| | - Marianne Strohmeyer
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Mimmo Roselli
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Gabriella Cancrini
- Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma Sapienza, Roma, Italy
| | - Piero Olliaro
- Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - Antonio Montresor
- Department of Control of Neglected Tropical Diseases (NTD), World Health Organization, Geneva, Switzerland
| | - Alessandro Bartoloni
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
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18
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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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Mushonga B, Habarugira G, Birori A, Kandiwa E, Samkange A, Bhebhe E. An epidemiological survey of the magnitude and local perceptions of porcine cysticercosis by two methods in Nyaruguru district, Rwanda. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2018; 14:18-24. [PMID: 31014726 DOI: 10.1016/j.vprsr.2018.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 07/28/2018] [Accepted: 07/30/2018] [Indexed: 10/28/2022]
Abstract
This study investigated the magnitude of porcine cysticercosis (PC), its risk factors, economic effects and the perceptions of 80 pig farmers from Nyabimata (n = 38) and Muganza (n = 42) and 20 registered butchers in the Nyaruguru district of Rwanda. January to December 2013 slaughter records from Kamirabagenzi market were also analysed for PC diagnoses based on the tongue test and meat inspection. During this period, the responding farmers' records showed a tongue test-based PC magnitude (3.9%, n = 984) which was lower than the collective tongue test-based PC magnitude of 9.2% (n = 1720) at Kamirabagenzi (p < .05). The overall magnitude of PC based on routine meat inspection diagnosis at Kamirabagenzi was 4%. The overall magnitude of PC for respondents using Free-range production systems (7.9%) was significantly greater than for those in Semi-intensive (2.1%) and Intensive production systems (1.5%) (p < .05). Though most farmers (90%) knew that PC is zoonotic, only 22.5% of the farmers opted for treatment of PC-infected pigs and 52.5% were willing to seek veterinary inspection while the rest (25%) opted to circumvent veterinary inspection (P > .05). Most butchers (70%) indicated they would circumvent veterinary inspection and continue to slaughter PC-positive animals whilst the rest (30%) indicated they would resell PC positive animals to defray costs (P < .05). The low sensitivity and specificity of methods used for PC detection in the study, implies that this may just be the tip of an iceberg and the actual magnitude is most likely to be much higher. In conclusion, PC is endemic in the Nyaruguru district of Rwanda with a high proportion of positive animals. The condition has public health implications and is worsening the economic plight of the impoverished Nyaruguru community.
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Affiliation(s)
- Borden Mushonga
- Department of Biomedical Sciences, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, Neudamm Campus, University of Namibia, P. Bag 13301, Pioneerspark, Windhoek, Namibia
| | - Gervais Habarugira
- School of Animal Sciences and Veterinary Medicine, University of Rwanda, P.O. Box 57, Nyagatare, Rwanda.
| | - Aloys Birori
- School of Animal Sciences and Veterinary Medicine, University of Rwanda, P.O. Box 57, Nyagatare, Rwanda
| | - Erick Kandiwa
- Department of Biomedical Sciences, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, Neudamm Campus, University of Namibia, P. Bag 13301, Pioneerspark, Windhoek, Namibia
| | - Alaster Samkange
- Department of Clinical Veterinary Studies, School of Veterinary Medicine, Faculty of Agriculture and Natural Resources, Neudamm Campus, University of Namibia, P. Bag 13301, Pioneerspark, Windhoek, Namibia
| | - Evison Bhebhe
- Department of Animal Science, School of Agriculture, University of Venda, Thohoyandou 0950, South Africa
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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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Davaasuren A, Davaajav A, Ukhnaa B, Purvee A, Unurkhaan S, Luvsan A, Logan JE, Ito A. Neurocysticercosis: A case study of a Mongolian traveler who visited China and India with an updated review in Asia. Travel Med Infect Dis 2017; 20:31-36. [PMID: 28478337 DOI: 10.1016/j.tmaid.2017.04.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/20/2017] [Accepted: 04/23/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Neurocysticercosis (NCC) of Taenia solium has never been reported in Mongolia. A Mongolian traveler who visited China and India presented with epileptic seizures after his return to Mongolia. Magnetic resonance imaging showed multiple ring enhancing lesions with edema surrounding several lesions in his brain that were initially diagnosed to be viral encephalitis or NCC. METHODS Serology for cysticercosis using diagnostic antigens partially purified by cation-exchange chromatography and chimeric recombinant antigens and DNA analysis of a proglottid found in the patient's stool were applied for differential diagnosis. RESULTS Serology showed strong positivity for NCC, and mitochondrial cox1 gene analysis revealed Indian but not Chinese haplotype of T. solium. CONCLUSION This NCC case was considered to be caused by eggs released from adult tapeworm(s) established after eating uncooked or undercooked pork contaminated with cysticerci during his stay in India. This is a case report of taeniasis and secondary NCC associated with travel to India with an updated review of NCC in Asia. Molecular tracking of the specimen is highly informative as a way to identify where the infection was acquired.
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Affiliation(s)
- Anu Davaasuren
- Laboratory of Parasitology, National Center for Communicable Diseases, Ulaanbaatar, Mongolia.
| | - Abmed Davaajav
- Laboratory of Parasitology, National Center for Communicable Diseases, Ulaanbaatar, Mongolia.
| | - Baigalmaa Ukhnaa
- Department of Radiology, Luxmed Hospital, Ulaanbaatar, Mongolia.
| | | | - Saraa Unurkhaan
- Neurology Center, The State Third Central Hospital, Ulaanbaatar, Mongolia.
| | - Amartuvshin Luvsan
- Department of Radiology, The State Third Central Hospital, Ulaanbaatar, Mongolia.
| | - Jenae E Logan
- Division of Infectious Disease, School of Medicine and Global Health Institute, Duke University, North Carolina, USA.
| | - Akira Ito
- Department of Parasitology, Asahikawa Medical University, Asahikawa, Japan.
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Hotez P, Aksoy S. PLOS Neglected Tropical Diseases: Ten years of progress in neglected tropical disease control and elimination … More or less. PLoS Negl Trop Dis 2017; 11:e0005355. [PMID: 28426662 PMCID: PMC5398476 DOI: 10.1371/journal.pntd.0005355] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
This year PLOS Neglected Tropical Diseases (PLOS NTDs) celebrates its tenth anniversary following the publication of the first issue in 2007 [1]. When PLOS NTDs was founded, the framework of the neglected tropical diseases (NTDs) as an alternative to “other diseases” (as they were then referred to in the Millennium Development Goals) was just getting started—especially for Africa [2, 3]. In the decade since, PLOS NTDs has overseen enormous successes in NTD control and elimination. Here, we want to briefly review the ten year progress made towards the control or elimination of the diseases now identified by the WHO as NTDs. Many of the details are highlighted in PLOS NTDs papers cited here, but the summary information is based on the recently released Global Burden of Disease (GBD) Study 2015 (also launched with Gates Foundation support) that summarized past-decade changes in disease prevalence, mortality, or disability rates (from the years 2005 to 2015) [4–6], as well as the GBD Study 2013 that summarizes disease prevalence changes over a longer time horizon from 1990 to 2013 [7].
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Affiliation(s)
- Peter Hotez
- Texas Children’s Hospital Center for Vaccine Development, National School of Tropical Medicine at Baylor College of Medicine, Houston, Texas, United States of America
- Department of Biology, Baylor University, Waco, Texas, United States of America
- Center for Health and Biosciences, James A. Baker III Institute for Public Policy, Rice University, Houston, Texas, United States of America
- Scowcroft Institute of International Affairs, Bush School of Government and Public Service, College Station, Texas, United States of America
- * E-mail: (PH); (SA)
| | - Serap Aksoy
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, Connecticut, United States of America
- * E-mail: (PH); (SA)
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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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