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The cystiSim model was used to compare strategies for the control of Taenia solium. A three-monthly intervention in pigs for 3 years was substantially more effective than biannual treatment for taeniasis in the human population for 5 years. The intervention period could be shortened further by combining pig and human interventions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: The zoonotic tapeworm Taenia saginata, although causing only minor discomfort in humans, is responsible for considerable economic losses in the livestock sector due to condemnation or downgrading of infected beef carcasses. An overview of current knowledge on the distribution and prevalence of this parasite in West and Central Africa is lacking., Methods: We conducted a systematic review, collecting information on published and grey literature about T. saginata taeniosis and bovine cysticercosis from 27 countries/territories in West and Central Africa, published between January 1st, 1990 and December 31st, 2017., Results: The literature search retrieved 1672 records, of which 51 and 45 were retained for a qualitative and quantitative synthesis, respectively. Non-specified human taeniosis cases were described for Nigeria, Cameroon, Senegal, Burkina Faso, Democratic Republic Congo, Guinea, and Ivory Coast (seven out of 27 countries/territories), while T. saginata taeniosis specifically was only reported for Cameroon. Most prevalence estimates for taeniosis ranged between 0-11%, while three studies from Nigeria reported prevalence estimates ranging between 23-50%. None of the studies included molecular confirmation of the causative species. The presence of bovine cysticercosis was reported for Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Democratic Republic Congo, Ghana, Guinea, Ivory Coast, Mali, Niger, Nigeria, Senegal, and Tristan da Cunha (14 out of 27 countries/territories). Prevalence estimates ranged between 0-29%., Conclusions: Our systematic review has revealed that human taeniosis and bovine cysticercosis are seriously understudied in West and Central Africa. The high prevalence estimates of both conditions suggest an active dissemination of this parasite in the region, calling for a concerted One Health action from public health, veterinary health and food surveillance sectors.

Background: The zoonotic parasite Taenia saginata transmits between humans, the definitive host (causing taeniosis), and bovines as the intermediate host (causing cysticercosis). Central and western Asia and the Caucasus have large cattle populations and beef consumption is widespread. However, an overview of the extent of human T. saginata infection and bovine cysticercosis is lacking. This review aims to summarize the distribution of T. saginata in this region., Methods: A systematic review was conducted, that gathered published and grey literature, and official data concerning T. saginata taeniosis and bovine cysticercosis in central and western Asia and the Caucasus published between January 1st, 1990 and December 31st, 2018. Where no data were available for a country within this period, published data from 1985-1990 were also accessed., Results: From 10,786 articles initially scanned, we retrieved 98 full-text articles from which data were extracted. In addition, two unpublished datasets were provided on the incidence of human taeniosis. Data for human taeniosis and bovine cysticercosis were found for all countries except Turkmenistan. Human taeniosis prevalence varied from undetected to over 5.3%, with regional variations. Where bovine cysticercosis was detected, prevalences varied from case reports to 25%., Conclusions: The public health burden of T. saginata is assumed to be small as the parasite is of low pathogenicity to humans. However, this review indicates that infection continues to be widespread and this may result in a large economic burden, due to the resources utilized in meat inspection and condemnation or processing with subsequent downgrading of infected carcasses.

Background: Taenia solium taeniosis/cysticercosis is a public health and agricultural problem, especially in low-income countries, and has been ranked the top foodborne parasitic hazard globally. In 2012, the World Health Organization published a roadmap that called for a validated strategy for T. solium control and elimination by 2015. This goal has not been met, and validated evidence of effective control or elimination in endemic countries is still incomplete. Measuring and evaluating success of control programmes remains difficult, as locally acceptable targets have not been defined as part of the 2012 roadmap nor from other sources, and the performance of tools to measure effect are limited., Discussion: We believe that an international agreement supported by the tripartite World Health Organization, Food and Agriculture Organization of the United Nations, and World Organisation for Animal Health is needed to facilitate endemic countries in publicising SMART (Specific, Measurable, Achievable/attainable, Relevant, Time-bound) country-level control target goals. These goals should be achievable through locally acceptable adoption of options from within a standardised 'intervention tool-kit', and progress towards these goals should be monitored using standardised and consistent diagnostics. Several intervention tools are available which can contribute to control of T. solium, but the combination of these - the most effective control algorithm - still needs to be identified. In order to mount control efforts and ensure political commitment, stakeholder engagement and funding, we argue that a stepwise approach, as developed for Rabies control, is necessary if control efforts are to be successful and sustainable., Conclusions: The stepwise approach can provide the framework for the development of realistic control goals of endemic areas, the implementation of intervention algorithms, and the standardised monitoring of the evaluation of the progress towards obtaining the control target goals and eventually elimination.

Background: Russia is traditionally an endemic area for Taenia saginata infection, where a programme for the prevention of infection has been implemented for sixty years. This paper aims, therefore, to review the recent epidemiology data of Taenia saginata infection in the Russian Federation., Methods: We undertook a systematic review of published and grey literature, and official data for information on the incidence, prevalence and distribution of Taenia saginata taeniosis and cysticercosis in the Russian Federation between 1st January 1991 and 31st December 2017., Results: From the 404 records returned by our search strategy, we identified 17 official county reports, 17 papers and one meeting abstract on the occurrence of taeniosis or cysticercosis from the Russian Federation, eligible for inclusion in this study. In the Russian Federation, Taenia saginata infection has been continuously present and notifiable in the study period between 1991-2016. In the same area, a continuous decrease in the incidence of human taeniosis cases was observed, from 1.4 to 0.04 cases per 100,000 inhabitants, as well as a reduction in the territory where the infection is reported. The prevalence of bovine cysticercosis, ranging between 0.1-19.0%, generally has a declining trend, especially after 2005., Conclusions: Importance of Taenia saginata infection as a medical and veterinary problem has been decreasing in the 21st century but it is still an infection with health and economic impact in the Russian Federation.

Background: The beef tapeworm, Taenia saginata, causing cysticercosis in bovines and taeniosis in humans, is thought to have a global distribution. In eastern and southern Africa, cattle production plays a crucial role in the economy, but a clear overview of the prevalence of T. saginata in the region is still lacking. This review aims to summarize existing knowledge on T. saginata taeniosis and bovine cysticercosis distribution in eastern and southern Africa., Methods: A systematic review was conducted, that gathered published and grey literature, including OIE reports, concerning T. saginata taeniosis and bovine cysticercosis in eastern and southern Africa published between January 1st, 1990 and December 31st, 2017., Results: A total of 1232 records were initially retrieved, with 78 full text articles retained for inclusion in the database. Unspecified taeniosis cases were reported for Angola, Ethiopia, Kenya, Madagascar, Malawi, South Africa, Tanzania, Uganda and Zambia, whereas T. saginata taeniosis cases were found for Ethiopia, Kenya, South Africa, Tanzania, Zambia and Zimbabwe. The prevalence of taeniosis ranged between 0.2-8.1% based on microscopy, and between 0.12-19.7% based on coproAg-ELISA. In Ethiopia, the percentage of tapeworm self-reporting was high (45.0-64.2%), and a substantial number of anthelmintic treatments were reported to be sold in towns. The presence of bovine cysticercosis was reported in all 27 countries/territories included in the study, except for Rwanda and Somalia, Comoros, Madagascar, Mauritius, Mayotte, Seychelles and Socotra. The prevalence of cysticercosis ranged between 0.02-26.3% based on meat inspection, and between 6.1-34.9% based on Ag-ELISA., Conclusions: Although T. saginata has been reported in the majority of countries/territories of the study area, T. saginata taeniosis/cysticercosis remains a largely ignored condition, probably due to the absence of symptoms in cattle, the lack of data on its economic impact, and the fact that human taeniosis is considered a minor health problem. However, the occurrence of bovine cysticercosis is a clear sign of inadequate sanitation, insufficient meat inspection, and culinary habits that may favour transmission. Measures to reduce transmission of T. saginata are therefore warranted and the infection should be properly monitored.

Background: The distribution of Taenia saginata in the Americas is unclear. Establishing the distribution, economic burden, and potentials for control of bovine cysticercosis is increasingly important due to the growing demand for beef. This paper aims to take the first step and reviews the recent distribution of T. saginata taeniosis and bovine cysticercosis on a national level within the Americas., Methods: We undertook a systematic review of published and grey literature for information on the occurrence, prevalence, and geographical distribution of bovine cysticercosis and human taeniosis in the 54 countries and territories of the Americas between January 1st, 1990 and December 31st, 2017. Data on bovine cysticercosis from OIE reports from 1994 to 2005 were also included., Results: We identified 66 papers from the Americas with data on the occurrence of taeniosis or bovine cysticercosis and an additional 19 OIE country reports on bovine cysticercosis. Taeniosis was reported from 13 countries, with nine of these countries reporting specifically T. saginata taeniosis, and four countries reporting non-species specific taeniosis. The reported prevalence of taeniosis ranged between 0.04-8.8%. Bovine cysticercosis was reported from 19 countries, nine identified through the literature search, and an additional 10 identified through the OIE country reports for notifiable diseases. The reported prevalence of bovine cysticercosis ranged between 0.1-19%. Disease occurrence was restricted to 21 countries within the Americas, the majority from the mainland, with the only island nations reporting either bovine cysticercosis or taeniosis being Cuba, Haiti, and the US Virgin Islands., Conclusions: Taenia saginata is widely distributed across 21 of the 54 countries in the Americas, but insufficient epidemiological data are available to estimate the subnational spatial distribution, prevalence, incidence and intensity of infections. This needs to be addressed through active surveillance and disease detection programmes. Such programmes would improve the data quantity and quality, and may enable estimation of the economic burden due to bovine cysticercosis in the region in turn determining the requirement for and cost-effectiveness of control measures.

This study evaluated the effect of mass drug administration (MDA) with praziquantel administered to school-aged children (SAC) combined with 'track and treat' of taeniosis cases in the general population on the copro-antigen (Ag) prevalence of taeniosis. The study was conducted in 14 villages in Mbozi and Mbeya district, Tanzania. SAC made up 34% of the population and received MDA with praziquantel (40mg/kg) in 2012 (both districts) and in 2013 (Mbozi only). Three cross-sectional population-based surveys were performed in 2012 (R0), 2013 (R1), and 2014 (R2). In each survey approximately 3000 study subjects of all ages were tested for taeniosis using copro-Ag-ELISA. In total 9064 people were tested and copro-Ag-ELISA positive cases were offered treatment 6-8 months after sampling. The copro-Ag prevalence of taeniosis was significantly higher (Χ 2 -test, p=0.007) in Mbozi (3.0%) at R0 compared to Mbeya (1.5%). Twelve months after MDA in both districts (R1), the copro-Ag prevalence had dropped significantly in both Mbozi (2.0%, p=0.024) and in Mbeya (0.3%, p=0.004), but the significant difference between the districts persisted (Χ 2 -test, p<0.001). Ten months after the second round of MDA in Mbozi and 22 month after the first MDA (R2), the copro-Ag prevalence had dropped significantly again in Mbozi (0.8%, p<0.001), but had slightly increased in Mbeya (0.5%, p=0.051), with no difference between the two districts (Χ 2 -test, p=0.51). The taeniosis cases tracked and treated between round R0 and R2 represented 9% of the projected total number of taeniosis cases within the study area, based on the copro-Ag prevalence and village population data. Among SAC in Mbozi, infection significantly decreased at R1 (p=0.004, OR 0.12, CI: 0.02-0.41) and R2 (p=0.001, OR 0.24, CI: 0.09-0.53) when comparing to R0. In Mbeya infection significant decreased at R1 (p=0.013, OR 0.14, CI: 0.02-0.55), but no difference was found for R2 (p=0. 089), when comparing to R0 among SAC. This study showed that school-based MDA with praziquantel in combination with 'track and treat' of taeniosis cases significantly reduced the copro-Ag prevalence of taeniosis, and that annual MDA was significantly better than single MDA. The persistence of taeniosis cases illustrates that a One Health approach must be emphasized for effective control., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Health education has been recognised as a specific intervention tool for control of Taenia solium taeniosis/cysticercosis but evaluation of the efficacy of the tool remains. The aim of our study was to assess the effect of a computer-based T. solium health education tool 'The Vicious Worm' on knowledge uptake among professionals and investigate attitudes towards the program. The study was carried out between March and May 2014 in Mbeya Region, Tanzania, where T. solium is endemic. The study was a pre and post assessment of a health education tool based on questionnaire surveys and focus group discussions to investigate knowledge and attitudes. A total of 79 study subjects participated in the study including study subjects from both health- and agriculture sector. The health education consisted of 1½h individual practice with the computer program. The baseline questionnaire showed an overall knowledge on aspects of acquisition and transmission of T. solium infections (78%), porcine cysticercosis treatment (77%), human tapeworm in general (72%), neurocysticercosis in general (49%), and porcine cysticercosis diagnosis (48%). However, there was a lack of knowledge on acquisition of neurocysticercosis (15%), prevention of T. solium taeniosis/cysticercosis (28%), and relation between porcine cysticercosis, human cysticercosis, and taeniosis (32%). Overall, the study subject's knowledge was significantly improved both immediately after (p=0.001) and two weeks after (p<0.001) the health education and knowledge regarding specific aspects was significantly improved in most aspects immediately after and two weeks after the health education. The focus group discussions showed positive attitudes towards the program and the study subjects found 'The Vicious Worm' efficient, simple, and appealing. The study revealed a good effect of 'The Vicious Worm' suggesting that it could be a useful health education tool, which should be further assessed and thereafter integrated in T. solium taeniosis/cysticercosis control., (Copyright © 2016. Published by Elsevier B.V.)

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., Competing Interests: The authors have declared that no competing interests exist.

Background: This study aimed to map the distribution of Taenia solium taeniosis/cysticercosis and the co-distribution with schistosomiasis in Africa. These two major neglected tropical diseases are presumed to be widely distributed in Africa, but currently the level of co-distribution is unclear., Methods: A literature search on T. solium taeniosis/cysticercosis was performed to compile all known studies on the presence of T. solium and apparent prevalence of taeniosis and porcine cysticercosis in Africa. Studies were geo-referenced using an online gazetteer. A Bayesian framework was used to combine the epidemiological data on the apparent prevalence with external information on test characteristics to estimate informed district-level prevalence of taeniosis and porcine cysticercosis. Districts with T. solium taeniosis/cysticercosis presence were cross-referenced with the Global Neglected Tropical Diseases Database for schistosomiasis presence., Results: The search strategies identified 141 reports of T. solium in Africa from 1985 to 2014 from a total of 476 districts in 29 countries, 20 with porcine cysticercosis, 22 with human cysticercosis, and 16 with taeniosis, in addition to 2 countries identified from OIE reports. All 31 countries were considered, on national scale, to have co-distribution with schistosomiasis. Presence of both parasites was confirmed in 124 districts in 17 countries. The informed prevalence of taeniosis and porcine cysticercosis were estimated for 14 and 41 districts in 10 and 13 countries, respectively., Conclusions: With the paucity of data, T. solium infection is grossly under-reported and expected to be more widespread than this study suggests. In areas where co-distribution occurs there is a need for increased emphasis on evaluation of integrated intervention approaches for these two helminth infections and allocation of resources for evaluating the extent of adverse effects caused by mass drug administration.