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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., Competing Interests: Uffe C. Braae is currently employed by Novo Nordisk A/S. There is no conflict of interest to declare for other authors, (© 2023 The Authors.)

Taenia solium diagnosis is challenging as trained personnel, good diagnostic tools, and infrastructure is lacking in resource-poor areas. This paper aims to describe the study trial design adopted to evaluate a newly developed rapid point-of-care test that simultaneously detects taeniosis and neurocysticercosis (TS POC) in three district hospitals in Tanzania. The two-stage design included three types of patients: patients with specific neurological signs and symptoms (group 1); patients with complaints compatible with intestinal worm infections (group 2); patients with other symptom(s) (group 3). For group 1, all patients were tested using the TS POC test (stage 1), after which all positive, and a subset of negative, patients were selected for laboratory reference tests, clinical examination, and a brain computed tomography (CT) scan (stage 2). For groups 2 and 3, a similar design was adopted, but clinical examination and a brain CT scan (stage 2) were only performed in patients who were TS POC test-positive for cysticercosis. Due to the lack of a gold standard, a Bayesian approach was used to determine test accuracy for taeniosis and cysticercosis. For neurocysticercosis, a composite case definition was used as the reference standard. If successful, this study will help the future developments (commercialization and implementation) of the rapid test and improve patient management and disease prevention.

Field-applicable, high-quality, and low-cost diagnostic tools are urgently needed for Taenia solium . The aim of this paper is to describe the design, challenges, and rationale for the design of a diagnostic accuracy study in low-resource community settings in Zambia. The trial was designed as a prospective study with a two-stage design to evaluate a new point-of-care test (TS POC) for the detection of taeniosis and (neuro)cysticercosis. Participants within randomly selected households were tested with the TS POC test (index test). Participants who tested TS POC positive for taeniosis and/or cysticercosis and a subset of the negatives were requested to give blood and stool samples for reference testing, and to undergo clinical examination and a cerebral CT scan. The difficulties of conducting a clinical trial in settings with limited research and neuroimaging infrastructure as well as peculiarities specifically related to the disease (low prevalence of taeniosis and the lack of a gold standard) were taken into consideration for the design of this study. The two-stage design increased the efficiency of the study by reducing the number of samples, clinical examinations, and CT scans. Simplified flows and sampling processes were preferred over complex follow-up and randomization systems, aiming to reduce bias and increase the generalizability of the study.

Taenia spp. are responsible for a substantial health and economic burden in affected populations. Knowledge of the fate of the eggs of Taenia spp. in the environment and of other factors facilitating the transmission of eggs to intermediate hosts is important for the control/elimination of infections caused by Taenia spp. The aim of this systematic review was to summarize current knowledge of the factors influencing the survival and dispersal of Taenia spp. eggs in the environment. Publications retrieved from international databases were systematically reviewed. Of the 1465 papers initially identified, data were ultimately extracted from 93 papers. The results of this systematic review indicate that survival is favoured at moderate temperatures (0-20 °C). Humidity seems to affect the survival of Taenia spp. eggs more than temperature. Under field circumstances, Taenia spp. eggs have been found to survive for up to 1 year. Taenia spp. eggs are commonly found on vegetables (0.9-30%) and in soil and water samples (0-43%), with their presence posing a risk to the consumer. Invertebrates may act as transport hosts, transferring the infection to an intermediate host, but the importance of this route of transmission is still open to question. Wastewater treatment systems are not capable of entirely eliminating Taenia spp. eggs. Access to surface water and the use of sewage sludge as fertilizer on pastures are important risk factors for bovine cysticercosis. Although information on the survival and spread of Taenia spp. eggs is available, in general the data retrieved and reviewed in this article were old, focused on very specific geographical regions and may not be relevant for other areas or not specific for different Taenia spp. Furthermore, it is unknown whether egg survival differs according to Taenia sp. Future studies are necessary to identify sustainable methods to identify and inactivate parasite eggs in the environment and reduce their spread.

Background: Taenia solium is a zoonotic parasite responsible for neurocysticercosis-a major cause of late-onset acquired epilepsy in humans. Lack of affordable, specific and sensitive diagnostic tools hampers control of the parasite. This study assessed the performance of an antigen detection enzyme-linked immunosorbent assay (Ag-ELISA) in the diagnosis of viable T. solium cysticercosis in naturally infected slaughter-age pigs in an endemic area in Tanzania., Methods: A total of 350 pigs were bled before they were slaughtered and their carcases examined. Serum was analyzed for circulating antigens by using a monoclonal antibody-based B158/B60 Ag-ELISA. Each carcase was examined for the presence of Taenia hydatigena cysticerci and half carcase musculature together with the whole brain, head muscles, tongue, heart and diaphragm were sliced with fine cuts (< 0.5 cm) to reveal and enumerate T. solium cysticerci. Half carcase dissection can detect at least 84% of infected pigs. Prevalence and their 95% confidence intervals (CI) were calculated in Stata 12. Sensitivity, specificity, predictive values and likelihood ratios were determined., Results: Twenty-nine pigs (8.3%, 95% CI: 5.6-11.7%) had viable T. solium cysticerci while 11 pigs had T. hydatigena cysticerci (3.1%, 95% CI: 1.6-5.5%). No co-infection was observed. Sixty-eight pigs (19.4%, 95% CI: 15.4-20%) tested positive on Ag-ELISA; of these, 24 had T. solium cysticerci and 7 had T. hydatigena cysticerci. Sensitivity and specificity were determined to be 82.7% and 86.3%, respectively. Positive and negative predictive values were 35.2% and 98.2%, respectively. Likelihood ratios for positive and negative Ag-ELISA test results were 6.0 and 0.2, respectively. There was a significant positive correlation between the titre of circulating antigens and intensity of T. solium cysticerci (r (348)  = 0.63, P < 0.001)., Conclusions: The Ag-ELISA test characteristics reported in this study indicate that the test is more reliable in ruling out T. solium cysticercosis in pigs, than in confirming it. Hence, a negative result will almost certainly indicate that a pig has no infection, but a positive result should always be interpreted with caution. Estimates of T. solium prevalence based on Ag-ELISA results should, therefore, be adjusted for test performance characteristics and occurrence of T. hydatigena.

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

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.

Objective: Taenia solium taeniosis is a growing health problem in large parts of the world including Sub-Saharan Africa. Humans are infected by eating undercooked pork with T. solium metacestodes, which cause taeniosis. The aim of the present study was to assess the effect of increasing temperatures on T. solium metacestode viability in pork., Methods: Heavily T. solium infected pieces of pork were cooked in a water-bath at five different temperatures (40 °C, 50 °C, 60 °C, 70 °C and 80 °C) for 10-60 min. At each temperature/time point, five 5x5x5 cm pieces of pork fitted with thermometers at the core were placed in the water-bath. Controls were kept at 5 °C throughout exposure. After exposure, approximately 100 intact metacestodes were harvested and after a maximum of 6 h incubation at 37 °C in a culture media consisting of 50% porcine bile and 50% saline, the metacestodes were evaluated for viability., Results: The metacestodes were fully viable after cooking at a core temperature of 40 °C for up to an hour. The metacestodes were non-viable after cooking for >40 min at a core temperature over 50 °C. All metacestodes were dead after cooking for 30 min at a core temperature of 60 °C; at 70 °C, non-viability was found after 20 min and all metacestodes were dead after 10 min cooking at 80 °C., Conclusion: Findings showed that pork pieces cooked at >80 °C for >10 min proved safe for human consumption. This means that dishes consisting of pork pieces in sizes not greater than a 5 cm cube which are immersed in continuously boiling water for at least 10 min would be safe to eat. However, pork deep-fried in oil may entail a risk due to generally shorter cooking time. More research on the cooking practises is needed in order to produce safe guidelines for risk-free pork consumption., Competing Interests: Declarations of interest None., (Copyright © 2020. Published by Elsevier B.V.)

Education on pig farming has been recognized as an important method of transferring knowledge and improving production among smallholder pig producers in rural settings, but the effectiveness of this in different rural settings remains unknown. A community-based intervention trial on smallholder pig farmers was conducted with the aim of evaluating the effectiveness of pig farming education. Baseline information was collected using interview-based questionnaires and observations regarding pig welfare and husbandry practices followed by participatory pig farming education and field demonstrations. The study was carried out between May 2014 and May 2016 and involved 90 smallholder pig farmers from six villages in Angónia district, of Tete province in Mozambique. The baseline questionnaire among several aspects regarding pig management highlighted that most farmers had an overall knowledge on aspects of transmission (55.1%) and prevention (48.9%) of African swine fever (ASF), porcine cysticercosis (PC) transmission (8.2%), and field diagnosis (36.7%), and they were not aware of the zoonotic potential of PC or the basic husbandry procedures of pigs kept under permanent confinement. Forty-nine of the 90 farmers enrolled, participated in the pig farming education, which provided the basis for making a comparison between trained (54%) and non-trained (46%) pig farmers. Since knowledge for ASF transmission (P < 0.036), pig pen design (P < 0.014), reasons for confine the pigs (P < 0.016), as well as the adoption of the new introduced pig pen model (P < 0.025), and the practices of acceptable, good hygiene of the pig pen (P < 0.009 and P < 0.014, respectively), improved significantly in both groups, a remarkable spill-over was observed, proving villagers capable of transferring knowledge within the villages. However, water provision and total confinement in both groups were still not practiced by the most farmers following the pig farming education (P > 0.174 and 0.254). It is concluded that despite improved knowledge, the farmers failed to follow several recommendations, most likely due to poverty such as lack of basic resources like food and water, which even the farmers themselves lacked for their day to day living.

Background: Toxoplasma gondii is found worldwide, and consumption of undercooked meat is considered a significant risk factor for human infections. In Denmark, little is known about the distribution of T. gondii, but a recent study revealed a seroprevalence of 34% in Danish indoor sows. The present cross-sectional study aimed to investigate the role of mice for the transmission of T. gondii in Danish indoor sow herds., Results: In total, 56 sow herds were visited, 137 mice were caught by snap traps from 32 farms, and 52 cat faecal samples were collected from 22 farms. Eight percent of the mice were positive for T. gondii DNA, representing 11% of the farms. Significant associations were found between the presence of T. gondii-positive mice and both open feed systems (P= 0.041) and extra rodent control on the farm (P= 0.024). All cat faecal samples were deemed negative for T. gondii by light microscopy examination and real-time polymerase chain reaction analysis., Conclusion: Mice captured inside Danish sow herds were found to be infected with T. gondii and may thus contribute to the transmission of T. gondii to sows, which may explain the high seroprevalence found in Danish pigs.

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

Background: Taenia solium is a zoonotic tapeworm widely distributed across sub-Saharan Africa. Specific health education is regarded as a central element in controlling T. solium. In 2014, an electronic health education tool called 'The Vicious Worm', which was concerned with prevention of T. solium was introduced to health and agricultural professionals in Mbeya, Tanzania, an endemic setting. Introduction to ´The Vicious Worm' of 1.5 hours significantly improved the participants' knowledge. This study revisited the same study subjects one year later to assess persistence of knowledge regarding T. solium taeniosis/cysticercosis and to assess if the health education had changed work practices for the participants and the public., Methods: The study was conducted in Tanzania between June and August 2015, with a fixed population of health and agricultural professionals recruited from a previous study testing 'The Vicious Worm'. The study used a test, a questionnaire survey, as well as semi-structured group and individual interviews., Results: The 79 study subjects, all health or agricultural professionals, had within one year relocated from Mbeya to 16 of 21 administrative regions of Tanzania. Sixty-four agreed to participate in the test and 48 to an interview. The test showed significant improvement in knowledge regarding T. solium taeniosis/cysticercosis, compared with the baseline knowledge level of the participants. Interview data found that the participants had used 'The Vicious Worm' as an educational tool and applied the knowledge from the program to implement new practices consisting of by-laws and practical workshops on building latrines, pig pens and hand washing stations in their communities., Conclusion: Introduction to 'The Vicious Worm' led to changed practices and persistence in knowledge regarding T. solium. Incorporating health education as a specific health intervention tool should be encouraged and implemented at national or programmatic level., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

The presence and distribution of various species of canine hookworms in Africa are poorly known. The main objective of this study, therefore, was to identify the hookworm species present in canine faecal samples from Morogoro, Tanzania, using molecular techniques. Faecal samples from 160 local dogs were collected and hookworm positive samples processed to recover larvae for further molecular characterization. DNA was extracted from pools of larvae from individual samples (n = 66), which were analysed subsequently using two different molecular approaches, polymerase chain reaction-linked restriction fragment length polymorphism (PCR-RFLP) and species-specific PCR coupled with Sanger sequencing. The PCR-RFLP technique detected only the presence of the ubiquitous Ancylostoma caninum in the 66 samples. However, by species-specific PCR coupled with Sanger sequencing we identified ten samples with A. braziliense, two with Uncinaria stenocephala and five with A. ceylanicum. Thus, all four known species of canine hookworms were identified in Morogoro, Tanzania. To our knowledge this is the first report of the detection of the presence of U. stenocephala and A. ceylanicum in Africa using molecular techniques. In addition to their veterinary importance, canine hookworms have zoonotic potential and are of public health concern.

Background: Toxoplasma gondii is an important foodborne zoonotic parasite. Meat of infected animals is presumed to constitute a major source of human infection and may be a driver of geographical variation in the prevalence of anti- T. gondii antibodies in humans, which is substantial in the Nordic-Baltic region in northern Europe. However, data on seroprevalence of T. gondii in different animal species used for human consumption are scattered., Methods: We conducted a systematic review of seroprevalence studies and meta-analysis to estimate the seroprevalence of T. gondii in five animal species that are raised or hunted for human consumption in the Nordic-Baltic region: domestic pigs ( Sus scrofa domesticus ), sheep ( Ovis aries ), cattle ( Bos taurus ), wild boars ( Sus scrofa ), and moose ( Alces alces ). We searched for studies that were conducted between January 1990 and June 2018, and reported in articles, theses, conference abstracts and proceedings, and manuscripts. Subgroup analyses were performed to identify variables influencing the seroprevalence., Findings: From a total of 271 studies identified in the systematic review, 32 were included in the meta-analysis. These comprised of 13 studies on domestic pigs, six on sheep, three on cattle, six on wild boars, and four on moose. The estimated pooled seroprevalence of T. gondii was 6% in domestic pigs (CI 95% : 3-10%), 23% in sheep (CI 95% : 12-36%), 7% in cattle (CI 95% : 1-21%), 33% in wild boars (CI 95% : 26-41%), and 16% in moose (CI 95% : 10-23%). High heterogeneity was observed in the seroprevalence data within each species. In all host species except wild boars, the pooled seroprevalence estimates were significantly higher in animals >1 year of age than in younger animals. Not all studies provided information on animal age, sensitivity and specificity of the serological method employed, and the cut-off values used for defining an animal seropositive., Conclusions: A substantial proportion of animals raised or hunted for human consumption in the region had tested positive for T. gondii . This indicates widespread exposure to T. gondii among animals raised or hunted for human consumption in the region. Large variations were observed in the seroprevalence estimates between the studies in the region; however, studies were too few to identify spatial patterns at country-level.

Parasitic diseases have plagued mankind throughout history, and even today parasites continue to cause disease, disability and death in millions of people worldwide. Targeted electronic educational media for bringing awareness to local inhabitants of endemic communities, including public health practitioners, are vital tools in the battle against parasitic diseases., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

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: Taenia solium, a zoonotic tapeworm, is responsible for about a third of all preventable epilepsy human cases in endemic regions. In Europe, adequate biosecurity of pig housing and meat inspection practices have decreased the incidence of T. solium taeniosis and cysticercosis. Pigs slaughtered at home may have been raised in suboptimal biosecurity conditions and slaughtered without meat inspection. As a result, consumption of undercooked pork from home slaughtered pigs could pose a risk for exposure to T. solium. The aim of this study was to quantify the risk of human T. solium exposure from meat of home slaughtered pigs, in comparison to controlled slaughtered pigs, in European countries. A quantitative microbial risk assessment model (QMRA) was developed and porcine cysticercosis prevalence data, the percentage of home slaughtered pigs, meat inspection sensitivity, the cyst distribution in pork and pork consumption in five European countries, Bulgaria, Germany, Poland, Romania and Spain, were included as variables in the model. This was combined with literature about cooking habits to estimate the number of infected pork portions eaten per year in a country., Results: The results of the model showed a 13.83 times higher prevalence of contaminated pork portions from home slaughtered pigs than controlled slaughtered pigs. This difference is brought about by the higher prevalence of cysticercosis in pigs that are home raised and slaughtered. Meat inspection did not affect the higher exposure from pork that is home slaughtered. Cooking meat effectively lowered the risk of exposure to T. solium-infected pork., Conclusions: This QMRA showed that there is still a risk of obtaining an infection with T. solium due to consumption of pork, especially when pigs are reared and slaughtered at home, using data of five European countries that reported porcine cysticercosis cases. We propose systematic reporting of cysticercosis cases in slaughterhouses, and in addition molecularly confirming suspected cases to gain more insight into the presence of T. solium in pigs and the risk for humans in Europe. When more data become available, this QMRA model could be used to evaluate human exposure to T. solium in Europe and beyond.

Toxoplasma gondii is a zoonotic parasite of worldwide importance. In this study, we estimated T. gondii seroprevalence in extensively farmed wild boars in Denmark, where little is known about T. gondii in animal hosts. Our study focused on wild boars because they are considered good indicator species for the presence of T. gondii, and wild boar meat is used for human consumption. Serum samples from 101 wild boars collected in 2016-2018 from five different locations from the continental part of Denmark, Jutland, were screened for anti-T. gondii antibodies. The samples were analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA). Samples from 28 (27.7%) of the 101 wild boars tested positive with the ELISA. The odds for a wild boar to test seropositive were higher if it was sampled during the hunting season 2017-2018 than during 2016-2017 and if it was reported to be at least 1 year old than if it was younger (logistic regression model with the two variables: odds ratios 17.5 and 3.9, respectively). A substantial proportion of the investigated extensively farmed wild boars had been exposed to T. gondii. Moreover, the parasite appeared widespread, at least in the continental part of Denmark, Jutland, as seropositive wild boars were found from all five sampled locations. Assuming seropositivity indicates hosting viable parasites, consumption of undercooked wild boar meat from Denmark is a potential source of T. gondii infections to other hosts, including humans.

This study was conducted to evaluate effectiveness of an integrated management intervention in the control of endo- and ectoparasites of pigs kept by smallholder farmers in Mbeya Rural and Mbozi districts of southern highlands of Tanzania. A repeated cross-sectional group randomization design was employed, with 10 villages in the intervention group and six villages in the control group. The intervention consisted of improving pig confinement, feeds and feeding practices, and strategic anthelmintic treatment of pigs with oxfendazole, to primarily control Taenia solium (porcine) cysticercosis and nematodes; and with ivermectin to control ectoparasites and nematodes. Blood and faecal samples, ectoparasite specimens and skin scrapings were collected at baseline and two follow-up rounds, at an interval of seven months. A total of 482, 460 and 421 pigs were sampled in 221, 196 and 139 households at baseline, first and second follow-up visits respectively. Sero-prevalence of PC, prevalence and burden of gastrointestinal (GI) nematodes and prevalence of ectoparasites were determined using Ag-ELISA, McMaster faecal egg counting technique and body searches/skin scrapings, respectively. Mann Whitney test was used to measure intervention effect by comparing changes from baseline values of prevalence and faecal egg counts between the two groups. No significant difference (p > 0.05) was observed between the two groups, in changes from baseline of sero-prevalence of PC. The intervention significantly reduced prevalence of Trichuris suis (p = 0.044) and mean faecal egg counts of Ascaris suum (p = 0.02) from baseline to first follow-up. The intervention showed a substantial effect on the prevalence of ectoparasites as it significantly reduced overall prevalence of ectoparasites (p = 0.026), lice (p = 0.045), ticks (p = 0.049) and mites (p = 0.013) from baseline to first follow-up, and prevalence of ectoparasites, lice and mites from baseline to second follow-up (p = 0.052, p = 0.03, p = 0.017 respectively). This study has demonstrated a moderate effect of the intervention on controlling GI nematodes and ectoparasites, but no effect on sero-prevalence of PC. The reported ineffectiveness of the intervention against PC is probably an underestimation because serology is not able to provide quantitative data. It may also be a result of reduced compliance as this was a field study. Nevertheless, further studies are needed to better understand transmission dynamics of PC and explore One Health approaches including treatment of the human population against taeniosis to better secure public health., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Veterinary parasitology has always been considered to be relevant and interesting by the Danish veterinary students. Students have to acquaint themselves with many new, small creatures with complicated and varied life cycles and with intricate Latin names that are difficult to pronounce, as only a few parasites have Danish names. In our veterinary curriculum, zoology has disappeared as a discipline, and parasitology has gradually moved from the third year to the beginning of the second year, which implies that, for example, pathology and pharmacology are "unknown fields". The number of contact hours in veterinary parasitology has been gradually cut to 24 lectures (35 min each) and practical exercises (24 h), including 9 h on coprology. The course is taught and examined jointly with bacteriology and virology in a 8-week course. As a comprehensive course, it has become increasingly difficult to get students to acquire enough active knowledge of the most common parasites and an understanding of the basic principles in relation to, for example, transmission and control. Even though information is readily accessible through books and on-line resources, we still believe that a competent clinician should know a range of parasites by heart as an active resource for their work. The dilemma has been tackled (partly) by introducing a veterinary paraclinical refresher course of 18 h (half practicals and half lectures) in the fourth study year. The focus here is on host(herd)-oriented clinical and diagnostic parasitology. The students can also now select a One Health track for six months in which zoonotic parasites are obviously a relevant topic., (Copyright © 2018. Published by Elsevier B.V.)

Background: The zoonotic parasite Taenia solium is endemic in Angónia district, Tete province, Mozambique, though the burden of the disease complex is unknown., Methods: As part of two cross-sectional studies on human and porcine cysticercosis in the area, unique epidemiological and cost data were collected in Angónia district, Mozambique in 2007. These data provided the basis for the assessment of the societal cost of T. solium in the district, which estimates the impact of the disease on human and pig populations and includes both health and economic approaches in the analysis., Results: Approximately 0.7% (95% Uncertainty Interval (UI), 0.4-0.9) and 0.4% (95% UI, 0.2-0.6) of the total population in the district was estimated to suffer from neurocysticercosis (NCC)-associated epilepsy and headache. The estimated average number of disability-adjusted life years (DALYs) due to NCC-associated epilepsy and headache was 6 (95% UI, 4-8) per thousand persons per year. The total annual costs due to T. solium cysticercosis were estimated at 90,000 USD (95% UI, 39,483-201,463) of which 72% (95% UI, 45-91) were costs linked to human cysticercosis and 28% (95% UI, 9.5-55) to pig production losses. The annual economic burden per NCC-associated epilepsy case in the district amounted to 33 USD (95% UI, 10-76)., Conclusions: In this highly endemic area of Mozambique a large number of individuals suffer from symptoms associated with NCC. Healthy years of life are lost and people are left living with disabilities. Infected pork poses a serious risk to the community and affects the economy of smallholder farmers. Cost for treatment and hospitalization of patients with NCC-associated epilepsy, and lack of productivity and inability of suffering patients to work, further hinder socioeconomic development. Feasible solutions framed within a country specific algorithm and stepwise approaches are needed to control the parasite in the country.

A community-based intervention combining health education (HE) and treatment of pigs for control of porcine cysticercosis (PC), gastrointestinal (GI) helminths, African swine fever (ASF) and external parasites was tested involving six villages of resource-poor smallholder pig farmers. Farmers and pigs of six rural villages were randomly allocated into group 1 (HE), which served as controls, and group 2 (HE + OFZ) pigs received a single oral dose of 30 mg/kg OFZ. Farmers were trained in pig health, housing and feeding. The proportion of farmers with confined pigs, the adoption rate of the introduced pig pen, the sero-prevalence of PC and ASF, the prevalence and intensity of GI nematodes and the prevalence of ectoparasites were measured at 9, 15 and 24 months after initiation and compared to a baseline survey to seek the effectiveness of the interventions. There was no clear effect of the intervention on the sero-prevalence of PC, but analysis of the rate of change in prevalence between the two groups showed significant effect with the rate of change to lower prevalence in the HE + OFZ group compared to the HE group. Although HE managed to improve the farmer's knowledge in the control and prevention of ASF and ectoparasites, there was no significant reduction in the sero-prevalence of ASF and the prevalence of ectoparasites throughout the two-year period. The reported ineffectiveness of the intervention in this study suggested that more research is needed to develop more effective methods for controlling PC, ASF and pig parasites.

Taenia solium has been ranked as the most important foodborne parasite and Taenia saginata as the most commonly found human Taenia tapeworm worldwide. The last official reports of taeniosis from Estonia were in 2003 for T. solium and 2012 for T. saginata. By law, all animal cases of cysticercosis must be registered and reported when found. Our aim was to estimate the prevalence of cysticercosis in Estonia caused by T. solium in pigs and T. saginata in cattle. The four slaughterhouses participating in the study slaughter between them approximately 80% of pigs and cattle in Estonia annually. Sampling spanned from February to April 2014, visiting the slaughterhouses five times per week. Visual inspection, palpation, and incisions at predilection sites were used to find cysts in both species. The sites inspected in both species were the external masseter, tongue, heart, and diaphragm. In addition, the internal masseter in pigs was examined, and the internal pterygoid muscle and esophagus in cattle. DNA was extracted from the cysts and used for PCR amplification of the cox1-gene for Taenia genus and species identification. A total of 564 cattle and 1217 pigs were examined. Cysts were found in 0.36% (n = 2; CI 0.06-1.17) of cattle and in 0.08% (n = 1; CI 0.004-0.40) of pigs. Cestode PCR was negative from all cysts. Results should be considered taking into account the low sensitivity and specificity of finding cysts. Results reflect the situation in larger slaughterhouses, and the possibility that the situation in smaller slaughterhouses is different should not be excluded.

In 2015, the World Health Organisation rated toxoplasmosis as one of the most important food borne zoonotic diseases in the world. In addition, recent studies have associated Toxoplasma gondii sero-positivity with severe mental illnesses such as schizophrenia. Intake of raw or insufficiently cooked meat has been suggested to pose a major risk of T. gondii transmission in Europe. The objective of this study was to assess the T. gondii sero-prevalence in Danish pigs divided into sub populations (sows versus finishers, indoor versus outdoor). Serum samples were collected from 89 indoor-reared sows, 128 indoor finishers and 37 outdoor-reared finishers and analysed using an antibody ELISA with a sensitivity of 76.3% and a specificity of 93.7%. It was found that 33.7% indoor-reared sows, 3.1% indoor-reared finishers and 10.8% outdoor reared finishers were T. gondii sero-positive. The sero-positivity of T. gondii was significantly higher for indoor-reared sows compared to indoor-reared finishers (RR=10.9, (P<0.001). Although, the probability of T. gondii sero-positivity for outdoor-reared finishers was 3.5 times higher than for indoor-reared finishers, the difference was not statistically significant (P=0.14). The next step will be to identify specific risk factors for sero-positivity for indoor and outdoor production as well as for finishers and sows, and to use this information to help swine producers to prevent infection in their pigs., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The aim of this study was to measure hair cortisol and dehydroepiandrosterone (DHEA) concentrations in naturally Taenia solium infected and non-infected control pigs and assess the effect of an environmental change on the aforementioned parameters. Three hair patches were obtained from 13 T. solium infected and 15 non-infected controls sows, respectively corresponding to 3 time points (prior to, at and approximately two weeks after arrival at the research facility). Cortisol and DHEA were extracted using methanol and analysed by radio immune assay. Mean hair cortisol concentrations were significantly lower (p<0.001) in T. solium infected (4.7±3.0pg/mg) compared to control pigs (9.0±3.7pg/mg) prior to arrival at the research facility, however no significant difference was observed between the two groups at arrival and after approximately two weeks. Similar patterns were also observed for DHEA concentrations (infected pigs 253.9±82.3pg/mg, control pigs 387.7±116.4pg/mg) (p<0.001). Results showed that lean animals had significantly higher cortisol concentrations in both groups, infected and controls pigs, while DHEA was not significantly different between lean and normal animals. Results of this study have shown that an environmental change could have an effect on pigs' hormonal levels suggesting an undergoing adaptation process. After the pigs were kept under the same conditions, fed and watered ad libitum, no significant differences were observed between the groups, but a drop in DHEA concentrations was observed in all the pigs. Weight however had an effect on cortisol levels as lean animals had significantly higher cortisol concentrations in both groups, compared to normal pigs., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

Neurocysticercosis (NCC) is a disease caused by the zoonotic parasite Taenia solium lodging in the central nervous system. Both humans and pigs can get NCC. The impact of the disease in pigs has so far been little explored. The aim of this study was to describe the effect of NCC on social and feeding behaviours as well as the pattern of activity as indicators of reduced welfare in naturally infected sows. In total 13 T. solium naturally infected and 15 non-infected control sows were videotaped for 2 consecutive weeks using close circuit television cameras at research facilities at Sokoine University of Agriculture, Morogoro, Tanzania. Videos were analysed at the beginning, in the middle and at the end of the 2 week recording period. For each time point, videos were analysed during feeding, while the enrichment was provided, and by recording every half an hour the sows' behaviours performed over the course of a whole day. Sows with NCC spent significantly less time at the feeding trough, especially during the second half of the feeding period. Infected sows were also more passive e.g. lying and standing still significantly more during a whole day period and showed social isolation compared to non-infected control sows by performing behaviours more distant to their nearest neighbour. Results of this study indicated that NCC changed the behaviour of infected sows. The behavioural changes are indicative of decreased welfare. Efforts to reinforce the animal welfare aspect are needed as this has so far been neglected., (Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.)

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.)

Neurocysticercosis (NCC) is an important neurological disease in countries with high prevalence of Taenia solium infection and is emerging as a serious public health and economic problem. The aim of this study was to estimate the prevalence of NCC in Angónia district, Tete province, Mozambique based on: prevalence of human T. solium cysticercosis assessed by antigen Enzyme-linked Immunosorbent Assay (Ag-ELISA) seropositivity, history of epilepsy, and brain computed tomography (CT) scan results. A cross sectional study was conducted between September and November 2007 in Angónia district. Questionnaires and blood samples were collected from 1,723 study subjects. Brain CT-scans were carried out on 151 study subjects with confirmed history of epilepsy. A total of 77 (51.0% (95% CI, 42.7-59.2)) and 38 (25.2% (95% CI, 18.5-32.9)) subjects met the criteria for definitive and probable diagnosis of NCC, respectively. T. solium Ag-ELISA seropositivity was found in 15.5% (95% CI, 12.8-16.2) of the study subjects. The estimated life time prevalence of epilepsy was 8.8% (95% CI, 7.5-10.2). Highly suggestive lesions of NCC were found on CT-scanning in 77 (71.9%, (95% CI, 62.4-80.2)) of the seropositive and 8 (18.1%, (95% CI, 8.2-32.7)) of the seronegative study subjects, respectively. The present findings revealed a high prevalence of NCC among people with epilepsy in Angónia district. Determination of effective strategies for prevention and control of T. solium cysticercosis are necessary to reduce the burden of NCC among the affected populations., (Copyright © 2016. Published by Elsevier B.V.)

The World Health Organization announced in November 2014 at the fourth international meeting on 'the control of neglected zoonotic diseases - from advocacy to action', that intervention tools for eliminating Taenia solium taeniosis/cysticercosis (TSTC) are in place. The aim of this work was to elucidate theoretical outcomes of various control options suggested for TSTC elimination in sub-Saharan Africa (SSA) over a 4-year period. Our current knowledge regarding T. solium epidemiology and control primarily builds on studies from Latin America. A simple transmission model - built on data from Latin America - has been used to predict the effect of various interventions such as mass treatment of humans, vaccination and treatment of pigs, and health education of communities, potentially leading to change in bad practices and reducing transmission risks. Based on simulations of the transmission model, even a 4-year integrated One Health approach fails to eliminate TSTC from a small community and in all simulations, the prevalence of human taeniosis and porcine cysticercosis start to rise as soon as the programmes end. Our current knowledge regarding transmission and burden of TSTC in SSA is scarce and while claiming to be tool ready, the selection of diagnostic and surveillance tools, as well as the algorithms and stepwise approaches for control and elimination of TSTC remain major challenges.

Taenia solium taeniasis/cysticercosis is a neglected parasitic zoonosis with significant economic and public health impacts. Control measures can be broadly grouped into community health education, improvements in hygiene and sanitary conditions, proper meat handling at household and community level, improved standards of meat inspection, pig management, treatment of individual patients and possibly human populations, and treatment and/or vaccination of porcine populations. This manuscript looks critically into currently existing control options and provides suggestions on which (combination of) tools would be most effective in the control of T. solium taeniasis/cysticercosis in sub-Saharan Africa. Field data and disease transmission simulations suggest that implementation of a single intervention control strategy will not lead to a satisfactory reduction of disease morbidity or transmission. A feasible strategy to combat T. solium taeniasis/cysticercosis would include a combination of approaches focussing on both human (health education and treatment) and animal host (management, treatment and vaccination), which can vary for different communities and different geographical locations. Selection of the specific strategy depends on cost-effectiveness analyses based on solid field data, currently unavailable, though urgently needed; as well as on health priorities and resources of the country. A One Health approach involving medical, veterinary, environmental and social sectors is essential for T. solium to be controlled and eventually eliminated. Finally the success of any intervention is largely dependent on the level of societal and political acceptance, commitment and engagement., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The pork tapeworm, Taenia solium, causes an important economic and health burden, mainly in rural or marginalized communities of sub-Saharan Africa, Asia, and Latin-America. Although improved pig rearing conditions seem to have eliminated the parasite in most Western European countries, little is known about the true endemicity status of T. solium throughout Europe. Three recent reviews indicate that autochthonous human T. solium taeniasis/cysticercosis may be possible in Europe, but that current peer-reviewed literature is biased towards Western Europe. Officially reported data on porcine cysticercosis are highly insufficient. Favourable conditions for local T. solium transmission still exist in eastern parts of Europe, although the ongoing integration of the European Union is speeding up modernisation and intensification of the pig sector. Further evidence is urgently needed to fill the gaps on the European T. solium endemicity map. We urge to make human cysticercosis notifiable and to improve the reporting of porcine cysticercosis., (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.)

A cross-sectional study was carried out to determine the prevalence and associated risk factors of parasitic infections in pigs kept under smallholder farming system in Angónia district, Tete Province, Mozambique. A total of 262 pigs from 133 households of six villages were randomly selected. From each pig blood, faecal samples, full body searches, and skin scrapings were conducted to determine the prevalence of Taenia solium (using Ag-ELISA), gastrointestinal (GI) parasites, and ectoparasites respectively. A questionnaire survey was administered to smallholder pig farmers to assess their knowledge and perceptions of health and pig management and an observational study was conducted to determine their pig management practices. The overall prevalence of porcine cysticercosis by Ag-ELISA was 12.6%, GI nematodes 21.4%, Eimeria spp. 8.0% and ectoparasites 37.8%. Four helminths species namely, Metastrongylus spp., Hyostrongylus spp., Oesophagostomum spp., Trichostrongylus spp., were identified from by copro culture, and through faecal egg count, Ascaris suum and Trichuris suis were identified. Haematopinus suis, Rhipicephalus spp. and Echidnophaga gallinacea were found with a prevalence of 32.4%, 7.6%, and 6.9%, respectively. The only significant risk factor identified to be related to the parasite prevalence was pig origin (village), for both gastrointestinal parasites (OR=10.81[0.81-57.27]) and ectoparasites (OR=7.06[1.42-35.03]). This study provided evidence that parasitic infections in pigs constitute a major burden for smallholder pig farmers in Angónia district, and that porcine cysticercosis is a public health threat in the area and immediate attention is needed for control and prevention of the parasite., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Taenia solium is a zoonotic parasite prevalent in many low income countries throughout Latin America, Asia and sub-Saharan Africa, including Tanzania. The parasite is recognized as a public health threat; however the burden it poses on populations of Tanzania is unknown. The aim of this study was to estimate the societal cost of T. solium cysticercosis in Tanzania, by assessing both the health and economic burden. The societal cost of T. solium cysticercosis was assessed in humans and pigs based on data obtained by a systematic review. Experts' opinion was sought in cases where data were not retrievable. The health burden was assessed in terms of annual number of neurocysticercosis (NCC) associated epilepsy incident cases, deaths and disability-adjusted life years (DALYs), while the economic burden was assessed in terms of direct and indirect costs imposed by NCC-associated epilepsy and potential losses due to porcine cysticercosis. Based on data retrieved from the systematic review and burden assessments, T. solium cysticercosis contributed to a significant societal cost for the population. The annual number of NCC-associated epilepsy incident cases and deaths were 17,853 (95% Uncertainty Interval (UI), 5666-36,227) and 212 (95% UI, 37-612), respectively. More than 11% (95% UI, 6.3-17) of the pig population was infected with the parasite when using tongue examination as diagnostic method. For the year 2012 the number of DALYs per thousand 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. Our results show that T. solium imposes a serious public health, agricultural and economic threat for Tanzania. We urge that a One Health approach, which involves the joint collaboration and effort of veterinarians, medical doctors, agricultural extension officers, researchers and relevant governmental agencies, is taken to find sustainable solutions for prevention, control and elimination of T. solium., (Copyright © 2016 Elsevier B.V. All rights reserved.)

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.

Neurocysticercosis caused by infection with Taenia solium is a significant cause of epilepsy and seizures in humans. The aim of this study was to assess the association between seizures and the deposition of collagen in brain tissue in pigs with T. solium neurocysticercosis. In total 78 brain tissue sections from seven pigs were examined histopathologically i.e. two pigs with epileptic seizures and T. solium cysts, four pigs without seizures but with cysts, and one non-infected control pig. Pigs with epileptic seizures had a larger amount of collagen in their brain tissue, showing as large fibrotic scars and moderate amount of collagen deposited around cysts, compared to pigs without seizures and the negative control pig. Our results indicate that collagen is likely to play a considerable part in the pathogenesis of seizures in T. solium neurocysticercosis., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Taenia solium is found throughout sub-Saharan Africa and co-endemic with schistosomiasis in many regions. Taenia solium leads to taeniosis and neurocysticercosis - the leading cause of preventable epilepsy globally. This study aimed to assess the effects of the National Schistosomiasis Control Programme on prevalence of taeniosis and porcine cysticercosis over a four year period in Tanzania. School-based mass drug administration (MDA) of praziquantel was carried out based on schistosomiasis endemicity. Four human and five porcine cross-sectional surveys were carried out from 2012 to 2015 in Mbozi and Mbeya district in Tanzania. Three rounds of school-based MDA of praziquantel were delivered in Mbozi and two in Mbeya. The prevalence of taeniosis and porcine cysticercosis was estimated annually. Stool samples were collected from humans and prevalence of taeniosis estimated by copro-Ag-ELISA. Blood samples from pigs were collected to estimate cysticercosis prevalence by Ag-ELISA. "Track-and-treat" of taeniosis cases was carried out after each survey. In total 12082 stool samples and 4579 porcine serum samples were collected. Significantly fewer children (≤ 15) from Mbozi were infected throughout the study than children from Mbeya who showed a significant decrease in copro-Ag prevalence after the first treatment only. During the final survey in Mbozi the prevalence of taeniosis in adults (1.8%) was significantly lower (p = 0.031, OR 0.40, CI: 0.17-0.89), compared to baseline (4.1%). The prevalence of porcine cysticercosis (8%) had also dropped significantly (p = 0.002, OR 0.49, CI: 0.32-0.76) in this district compared to baseline (13%), whereas no significant difference was seen in Mbeya compared to baseline. The study suggests that three rounds of MDA targeting schistosomiasis in school-aged children combined with 'track-and-treat' contributed to a reduction in prevalence of T. solium in this population, and also had a spillover effect on adults in treated areas as well as reducing the prevalence of T. solium in the intermediate pig host population. Elimination of T. solium in this area would require a One Health approach.

Neurocysticercosis (NCC) caused by Taenia solium is a serious neurological disease. In humans neurological symptoms have been thoroughly studied and documented, however, there is limited information on clinical signs in pigs infected with T. solium cysticerci. Among the scientific community, it is in fact believed that pigs with NCC rarely show neurological signs. The aim of this study was to describe clinical manifestations associated with NCC in pigs and correlate the manifestations to the number and distribution of cysticerci in brains of naturally infected pigs in Tanzania. Sixteen infected and 15 non-infected control pigs were observed for 14 days during daylight hours, and subsequently videotaped for another 14 consecutive days using close circuit television cameras. All occurrences of abnormal behaviour (trembling, twitching, mouth and ear paralysis, ataxia, dribbling, salivating, eye blinking, walking in circles) were recorded. At the end of the recording period, pigs were slaughtered and their brains dissected, cysticerci counted and locations noted. During the recording period, two infected pigs were observed having seizures. Some of the observed autonomic signs during a seizure were chewing motions with foamy salivation and ear stiffening. Motor signs included tonic muscle contractions followed by a sudden diminution in all muscle function leading to collapse of the animal. Stereotypic walking in circles was observed on several occasions. At dissection, both pigs had a high number of brain cysticerci (241 and 247 cysticerci). The two pigs with seizures were also older (36 months) compared to the others (18.3 months, ± 8.2 standard deviation). Results of this study have shown that pigs with NCC can develop clinical signs and suffer from seizures like humans with symptomatic NCC. Results of this study could potentially open up a new experimental pathway to explore the aetiology of neurological symptoms in humans with NCC associated epilepsy., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Few studies have been carried out in Africa to estimate the prevalence of Taenia hydatigena. With the aim to determine the prevalence of T. hydatigena in slaughtered pigs and small ruminants (goats and sheep) in Mbeya, Tanzania, two cross-sectional surveys were carried out investigating pigs in April to May 2014 and small ruminants in September 2012. In total, 243 pigs were examined post-mortem for T. hydatigena cysts which were found in 16 (6.6 %) pigs. The majority (80 %) of cysts were found on the omentum and the rest on the liver (20 %), all on the visceral surface. Two pigs were also found infected with Taenia solium but showed no signs of other infections. A total of 392 goats and 27 sheep were examined post-mortem, and the prevalence of T. hydatigena was similar in goats and sheep with 45.7 and 51.9 %, respectively. DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) from a subsample of metacestodes from goats and sheep confirmed the T. hydatigena infection. The prevalence found in small ruminants was comparable to other studies conducted in Africa, but for pigs, it is one of the highest recorded to date. The present study also confirms the occurrence of T. hydatigena and T. solium in pigs from Mbeya. Further studies are needed to determine the impact of T. hydatigena on production under sub-Saharan conditions and the financial consequences for smallholder farmers.

Attempts to control Taenia solium in low-income countries have been unsuccessful or unsustainable. This could indicate a 'missing link' in our understanding of the transmission dynamics of the parasite and possibly the magnitude of environmental contamination. We aimed to identify risk factors associated with porcine cysticercosis using a case-control study design, utilising known information on persistent or multiple infections of porcine cysticercosis. The study, a combination of questionnaire interviews and observational surveys, was conducted in July 2014 in the two districts Mbeya and Mbozi, Tanzania. Study households were identified based on their status regarding porcine cysticercosis prevalence and allocated into cases or controls based on previous porcine cysticercosis presence. This resulted in 43 farmers in the case group and 50 farmers in the control group, from 20 villages. Potato peels were said to be given to pigs either raw or boiled by 46% of the farmers. Based on logistic regression porcine cysticercosis could be associated with absence or a completely open latrine (p=0.035, OR 5.98, CI: 1.33-43.02) compared to an enclosed latrine. Feeding potato peels to pigs was also associated with increased risk of infection (p=0.007, OR 3.45, CI: 1.43-8.79). Logistic analysis including the pig management system indicated pigs kept in elevated pens (p=0.049, OR 5.33, CI: 1.08-32.27) and on a dirt floor (p=0.041, OR 9.87, CI: 1.29-114.55) were more likely to be infected compared to a cemented floor. Whether potato peels are contaminated with Taenia eggs before they reach the household or whether the contamination is from water or dirty hands during the process of peeling, remains to be confirmed. This study suggests that detailed assessment of a number of areas of pig management is essential for designing effective control programmes., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Taenia solium taeniasis/cysticercosis is a neglected zoonotic disease complex occurring primarily in developing countries. Though claimed eradicated from the European Union (EU), an increasing number of human neurocysticercosis cases is being detected. Risk factors such as human migration and movement of pigs/pork, as well as the increasing trend in pig rearing with outside access are discussed in this review. The entry of a tapeworm carrier into the EU seems a lot more plausible than the import of infected pork. The establishment of local transmission in the EU is presently very unlikely. However, considering the potential changes in risk factors, such as the increasing trend in pig farming with outdoor access, the increasing human migration from endemic areas into the EU, this situation might change, warranting the establishment of an early warning system, which should include disease notification of taeniasis/cysticercosis both in human and animal hosts. As currently human-to-human transmission is the highest risk, prevention strategies should focus on the early detection and treatment of tapeworm carriers, and should be designed in a concerted way, across the EU and across the different sectors., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A cross-sectional study was carried out to determine risk factors for prevalence of common endo- and ectoparasites of pigs kept by smallholder farmers in Mbozi and Mbeya (Rural) districts of Mbeya Region, in Tanzania. A total of 482 pigs from 220 households of 16 villages, eight in each district were randomly selected and examined. Prevalence of Taenia solium cysticercosis was 11.5%, gastrointestinal nematodes 63.7% and ectoparasites 21.2% based on Ag-ELISA, McMaster technique and full body searches/ear scrapings, respectively. Nematode eggs identified were strongyles (Oesophagostomum spp. and Trichostrongylus spp.), Ascaris suum, Trichuris suis and Strongyloides ransomi with prevalence of 57.4%, 17.5%, 5.3% and 1.1%, respectively. Four groups of ectoparasites were identified, i.e. lice (Haematopinus suis), ticks (Rhipicephalus spp., Amblyomma spp., Haemaphysalis spp. and Boophilus spp.), fleas (Ctenocephalides canis) and mites (Sarcoptes scabiei var. suis and Demodex phylloides), with prevalence of 19.1%, 2.1%, 0.4%, and 1.2%, respectively. Pigs in Mbeya (Rural) District had higher odds for porcine cysticercosis (OR=2.63, 95% CI: [1.22-5.55]). Poor pen hygiene and infrequent antiparasitic treatment were identified to be risk factors for prevalence of nematode infections (OR=1.95 [1.09-3.52] and OR=1.78 [1.06-2.94], respectively). The odds for high nematode burdens increased in cases of poor pen hygiene (OR=4.20 [2.54-6.62]) and poor feed quality (OR=3.7 [1.66-8.33]). Pigs not treated with antiparasitic drugs within the last three months had higher odds for ectoparasite (OR=4.0 [1.78-9.09]) and lice infestations (OR=8.33 [1.96-14.28]) than treated pigs. This study has shown that parasitoses constitute a major burden for smallholder pigs in Mbeya Region and major risk factors included infrequent antiparasitic treatment, poor pen hygiene and poor feed quality. Cost-effective intervention strategies are needed to improve pork production, secure pig welfare and ensure safe pork for human consumption., (Copyright © 2015. Published by Elsevier B.V.)

Neurocysticercosis (NCC) caused by Taenia solium cysts is a frequent but neglected parasitic disease of the central nervous system (CNS) worldwide. The aim of this study was to describe anatomical locations of cysts in the CNS and the corresponding inflammation. A total of 17 naturally infected pigs were used to evaluate the distribution of cysts and, of these, seven were used to evaluate the corresponding inflammation further, through histopathology. Clinical signs in the pigs included dullness, sluggishness, somnolence, apathy and loss of consciousness. Cysts were distributed in all cerebral lobes, i.e. 39.7% in the frontal lobe, 20.3% in the parietal lobe, 20.0% in the occipital lobe and 19.7% in the temporal lobe, and only 0.4% in the cerebellum. No cysts were found in the spinal cord. Cysts were localized as follows: 47.9% in the dorsal subarachnoid, 46.9% in the parenchyma, 4.4% in the subarachnoid base and 0.9% in the ventricles. The results of the histopathology revealed lesions in an early inflammatory stage, i.e. stage I, in all anatomical locations except for two, which showed more of an inflammatory reaction, stage III, in one pig. It was concluded that clinical signs in pigs were neither pathognomonic nor consistent. These signs, therefore, cannot be used as a reliable indicator of porcine NCC. Furthermore, T. solium cysts were found to be in abundance in all cerebral lobes, and only a few were found in the cerebellum. Regarding the inflammatory response, no significant differences were found in the location and total number of cysts. Thus, further studies are needed to explain the determinants of cyst distribution in the CNS and assess in detail clinical signs associated with porcine NCC.

An on farm experiment was carried out to assess the effects of production systems on the performance of local pigs kept by smallholder farmers. Six villages from Mbeya and Mbozi districts, Tanzania were purposely selected based on the prominent pig production systems: free range, semi-confinement and total confinement. Fifteen pig keeping households were randomly selected from each village to participate in the study. A participatory rural appraisal and structured questionnaire were used for collecting information from the households on pig production and reproduction performance. In addition, a total of 180 weaner pigs, 2-3 months old, were purchased and randomly allocated to the 90 participating households. The pigs were subjected to three production systems: free range (M1), confinement with local diet (M2) and confinement with a compounded diet and anthelmintic treatment (M3). The anthelmintic treatment (piperazine citrate) was administered at 1 g per kg body weight. Faecal and blood samples were collected at month three of the experiment to assess the burden of intestinal helminths and sero-prevalence of Taenia solium cysticercosis, respectively. Sows kept under free range system were reported to have smaller litter size both at farrowing and at weaning compared to those kept under confinement. The experiment showed pigs under M3 had higher (P < 0.05) liveweight gains (136 g/day) compared to pigs in M2 (73 g/day) and M1 (68 g/day). In addition, pigs in M3 had higher body length and heart girth size with the feed to gain ratio of 8.5. Free range pigs tended to have lower faecal egg counts for most worm species compared to permanently confined pigs. Sero-prevalence of Taenia solium cysticercosis was 26%, with village prevalence ranging from 8 to 52%. Although pigs kept in M3 performed better than the rest, the compounded feed was too expensive for the farmers to afford. Locally available feed types combined with vitamin and mineral supplements may be a more sustainable option.

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.