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Cysticercosis, caused by larval stage of Taenia (T.) hydatigena is a disease of veterinary concern which causes major economic losses in livestock sector globally. Although livestock is the most productive part of Pakistan's economy, the epidemiological prevalence and genetic diversity of T. hydatigena has not been studied in great detail. Current study was undertaken for the estimation of the prevalence and genetic diversity of T. hydatigena among the goats and sheep of Multan in South Punjab, Pakistan. A PCR protocol targeting the cytochrome c oxidase subunit 1 (cox1) gene of T. hydatigena revealed an overall prevalence of 31.33 % among the small ruminants with higher prevalence in females (40.86 %) and older age group of >3-≤5 years (40.74 %). A total of 30 isolates were sequenced for partial mitochondrial cox1 gene which yielded 12 haplotypes with a haplotype diversity of 0.798 ± 0.68 and nucleotide diversity of 0.0046 ± 0.00183. A star like configuration was demonstrated in the haplotype network with a centrally positioned haplotype. Neutrality indices like Tajima's D and Fu's Fs were also biased towards negativity, a characteristic which suggests an expanding parasitic population. Moreover, the genetic diversity of T. hydatigena was also computed for the partial cox1 gene sequences available on GenBank, NCBI. A total of 415 sequences were retrieved out of which 142 haplotypes were identified having a haplotype diversity of 0.9150 ± 0.012 coupled with a nucleotide diversity of 0.00830 ± 0.00043. The haplotype profile of T. hydatigena population displayed an absence of a central haplotype, however, considerable genetic variation was ascertained. All the populations except Africa had a high haplotype diversity (>0.9), however, high Fst values were observed for a few populations which elucidated limited gene flow among the populations of Central/East Asia, Middle East, Europe and South Asia., Competing Interests: Declaration of Competing Interest Authors confirm that they have no conflict of interest of any sort with any one., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Porcine cysticercosis (PC) is an important public health problem, especially in sub-Saharan Africa, but limited information is available on the prevalence of infection in pigs entering the food chain. Existing diagnostic methods vary in accuracy and efficiency; whole carcass dissection is the most reliable method but is labour-intensive and destroys the carcass so can only be used in a research setting. Serological tests offer lower specificity, while meat inspection and lingual examination lack sensitivity, hampering accurate estimates and the removal of infected pigs from the food chain. Here, we provide the first estimates of PC prevalence in abattoirs in Rwanda. We use whole carcass dissection to determine the diagnostic accuracy of a commercial antigen-ELISA to estimate the true prevalence of infection across Rwanda and identify Taenia species affecting local pigs. We carried out a cross-sectional survey in 6 abattoirs across Rwanda (n = 744 pigs), with whole carcass dissection of a subset of 67 pigs. Cysts were detected in 20/67 (30%) of carcasses, with >1000 cysts in 9/20 (45%) of infected pigs. All cysts were identified as Taenia solium by PCR-RFLP, with no cysts of Taenia hydatigena found. The antigen-ELISA showed a sensitivity of 90% (95% CI: 68-99) and specificity of 85% (95% CI: 72-94), when compared to dissection. Using these estimates, the true prevalence was calculated as 25-43% in two abattoirs in south-west Rwanda, and 2-3% in the rest of the country. Fewer than half of infected pigs were detected by tongue palpation and post-mortem veterinary inspection. Our data indicate a high prevalence of PC in Rwandan abattoirs. Tongue palpation and veterinary inspections, as currently carried out, have little impact in removing cyst-infested pigs from the food chain. Additional interventions are needed, such as proper pig husbandry, treatment and vaccination against cysticercosis, health education, improved sanitation and hygiene, and improved processing and cooking of meat., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: AS and NR are members of the Government of Rwanda Neglected Tropical Diseases Technical Working Group. EMF is a Commissioner on the Lancet Commission on One Health and is a member of the Technical Advisory Group of the Government of Kenya Zoonotic Disease Unit., (Copyright: © 2024 Shyaka et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Parasite are living organisms which survive on another living being for their nourishment and survival. When these parasites resides on human body, they bring about inflammatory response. This inflammatory response leads to tissue reaction. Tissue response on microscopy appear as an eosinophilia, abscess and granulomas. This study was planned with the objective to know the frequency of parasite infection, tissue response in parasite infection and its comparison in terms of variables like age, sex and the type of parasite., Methods: This is a retrospective study, conducted in the department of pathology. A total of 26 cases of parasitic infections in human specimens reported in our department from January 2008 to December 2019 were included in this study. On all archived cases hematoxylin and eosin and where ever required periodic acid schiff was applied. These slides were thoroughly examined and clinicopathological correlation was studied., Results: Age range of patients was 5 years to 70 years. Maximum number of patients were belonging to 11-20 year age group. Male to female ratio was 1:2. Among the 26 cases, there were 9 cases (34.62%) of hydatid cyst, six cases of Entamoeba histolytica (23.07%), four cases of Enterobious vermicularis (15.38%), and two cases (7.69%) each of Ascaris lumbricoides , filaria and cysticercosis respectively. A specific tissue response seen in cysticercosis having chronic inflammatory cells, palisaded epithelioid cells granuloma and giant cell reaction while other showed inflammatory cells infiltration., Conclusion: Clinically diagnosis of parasitic infection in each and every case is not possible, similarly radiological investigation is also suggestive only. Histopathology examination is the benchmark investigation to diagnose parasite infection and tissue reaction to the host. Histopathology examination must be implicated in every case to identify parasite and tissue reaction so that the patients can be managed accordingly before the complications rises., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors.

Background: Cysticercosis is a zoonotic parasitic disease that poses a serious threat to public health. It is widely distributed and has a high incidence rate in China. Reports of disseminated cysticercosis worldwide are rare. This article presents a case of disseminated cysticercosis in the Guangxi Zhuang Autonomous Region of southwestern China., Case Presentation: The patient, a 46-year-old male belonging to the Miao ethnic group, hailed from a region in Guangxi Zhuang Autonomous Region known for its high incidence of cysticercosis. He had a habit of consuming raw pork and beef. With a history of recurrent consciousness disturbances and limb convulsions for five years, he presented with headaches and dizziness nine days prior. Comprehensive examinations were conducted on the patient. Ultimately, based on epidemiological history, imaging findings, pathogen testing, and pathological results, he was diagnosed with disseminated cysticercosis. Following anthelmintic treatment, the patient was discharged with clear consciousness, free from headaches, dizziness, nausea, vomiting, and seizures. The patient is currently under follow-up care., Conclusion: It is crucial to enhance public awareness, promote health education, and cultivate good hygiene habits, as these are essential measures in reducing the incidence of cysticercosis., (© 2024. The Author(s).)

Background: Taeniasis and cysticercosis are parasitic infections caused by Taenia spp., mainly transmitted through the consumption of undercooked pork. Prevention requires increasing knowledge and awareness, improving meat inspection and hygiene, and promoting safe food handling and sanitation. The aim of this study was to evaluate the knowledge and practice (KP) of residents in Pak Chong District, Nakhon Ratchasima, Thailand, regarding taeniasis and cysticercosis., Methods: A cross-sectional study was conducted in Pak Chong District, Nakhon Ratchasima, Thailand, and its 11 subdistrict municipalities. Study participants were selected using a stratified random sampling design. A validated questionnaire (Cronbach's alpha = 0.70) was used to collect socio-demographic information and assess knowledge and practices related to taeniasis and cysticercosis. Descriptive statistics and multiple linear regression were used for the analysis., Results: Of the 360 survey respondents, 65.0% (n = 234) were women, 82.2% (n = 296) were aged under 60 years, 99.2% (n = 357) identified as Buddhist, 87.5% (n = 315) had less than a bachelor's degree education level, 54.2% (n = 195) had monthly family income ≥10,000 Thai baht, 10.6% (n = 38) were unemployed, and 26.1% (n = 93) lived in a town municipality. The survey revealed that 98.3% (n = 354) of participants were categorized as having less accurate knowledge and 83.6% (n = 301) were classified as more frequently engaging in correct prevention practices. Our study revealed that pig farmers (1.7%) occasionally permitted the pigs to forage freely. The results of multiple linear regression analysis revealed that knowledge scores were positively associated with household income ≥10,000 Thai baht (βadj = 1.50, 95% confidence interval [CI] 0.65 to 2.36). Practice scores were negatively associated with age over 60 years (βadj = -1.77, 95% CI -3.14 to -0.40) and living in a subdistrict municipality (βadj = -2.58, 95% CI -3.77 to -1.39). There was no association between KP regarding taeniasis and cysticercosis in the population of Pak Chong., Conclusions: Overall, participants' knowledge was lacking. Public education interventions are recommended to improve knowledge among residents with low socioeconomic status. These findings can inform the development of targeted interventions and educational programs in Pak Chong District, especially among elderly people in subdistrict municipalities, to improve practices for the prevention and control of these parasitic infections., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Phumrattanaprapin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The cestode Taenia hydatigena uses canids, primarily dogs, as definitive hosts, whereas the metacestode larval stage cysticercus infects a range of intermediate hosts, including domestic animals such as goats, sheep and pigs., Objectives: In this study, we aimed to determine the genetic differences and haplotypes of Cysticercus tenuicollis isolates obtained from sheep and goats slaughtered in the Bingol and Elazig provinces of Turkey., Methods: C. tenuicollis isolates were collected from 44 sheep and 26 goats slaughtered in slaughterhouses in Bingol and Elazig. After the isolation of total genomic DNA from C. tenuicollis isolates, the genetic characterization of the partial mitochondrial cytochrome oxidase 1 (CO1) gene region (866 bp) was amplified using specific primers by polymerase chain reaction (PCR), the products were then sequenced, and haplotype and genetic diversity analyses were carried out., Results: As a result of the haplotype network analyses, 34 different haplotypes were detected around the main haplotype (Hap02) arranged in a star-like configuration and separated from other haplotypes by 1-28 mutation steps and covering 22.85% (16/70) of all isolates. Twenty-seven polymorphic fields were detected, 77.77% (21/27) of which were parsimony-informative, and secondary haplotype and nucleotide diversity were observed. Additionally, we detected high intraspecies haplotype diversity (hd: 0.933) and high nucleotide diversity (π: 0.00383), with 27 different nucleotide variation positions among the haplotypes of the isolates. Tajima's D value was negative, indicating population expansion and/or selection purification. The significantly negative Fu's Fs values indicated recent population expansion or the presence of expected rare haplotypes., Conclusion: The results of this study confirmed that C. tenuicollis isolates clustered in one lineage and were closely related to the relevant reference sequences in different countries, confirming the circulation of C. tenuicollis in different geographical regions., (© 2024 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

The pork tapeworm Taenia solium causes human taeniasis and cysticercosis when ingested as viable cysts and eggs, respectively. Despite its high health burden in low-income countries, knowledge of the parasite in endemic areas such as Rwanda is often limited. Here, we assess whether The Vicious Worm education software can increase knowledge in endemic areas of Rwanda. A cross-sectional mixed-methods study was conducted to evaluate knowledge about T. solium among community health workers trained using the Vicious Worm education software. Knowledge was assessed before, immediately after, and four weeks after the training. The health workers perceptions of the software were analysed thematically. A total of 207 community health workers were recruited from Nyamagabe district in Southern Province, Rwanda. Participants were composed of males (33.5%) and females (66.5%), aged between 22 and 68 years, and most (71%) had only completed primary education. Knowledge of cysticercosis at baseline was low, particularly knowledge of human cysticercosis and neurocysticercosis. The overall knowledge score increased significantly after training and was maintained four weeks after the training. Overall, insufficient knowledge was associated with neurocysticercosis-related questions, which after the training, remained relatively lower compared to questions of other categories. Participants reported the software to be user-friendly and educational. Digital illiteracy and the lack of smartphones were among the critical challenges highlighted in responses. This study has shown gaps in knowledge regarding T. solium infections within rural Rwanda, particularly neurocysticercosis. Health education using the Vicious Worm education software should be considered in integrated control programs., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Uwibambe et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The cysticercosis is a major zoonotic disease in many developing countries. This study was carried out to determine the prevalence of porcine cysticercosis and to identify potential risk factors associated and their seroprevalence as well in Benin. The tongue palpation was performed on 4150 pigs from the pig farmers were randomly selected to diagnose cysticercosis and to assess the risk factors associated. In slaughterhouses, 792 pigs were inspected. Serum samples from 460 pigs were tested of the presence of Taenia solium cysticercosis using the HP10 antigen-ELISA (Ag-ELISA). A logistic regression model with a 95% confidence interval was used to analyse the main risk factors associated. The tongue palpation revealed a prevalence of 4.79% at the level of slaughterhouses versus 7.82% in the post-mortem inspection. The Ag-ELISA revealed that more than 40% of the pigs were positive. The risk factors identified were the origin area of pigs, the history of cysticercosis in the farms, the presence or absence of a latrine, the pig-farming systems, the age class of pigs and the source of watering. In addition, 34.48% individuals was tested for taenia versus 13.79% for cysticercosis in the hospitals surveyed. Our results showed the major revelation of porcine cysticercosis and its very high level of risk for a public health in all departments of Benin. Therefore, this study suggests the need to continue epidemiological and sociological surveys with a "One Health" approach in order to design and implement effective control measures in this country of high consumption of pigs., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The epidemiological picture of Taenia saginata infections in Kenya is fragmented with limited available data. Although Sarcocystis species are significant meat-borne parasites, few studies have explored their occurrence in Kenya. This study aimed to estimate the occurrence of bovine cysticercosis and screen for the presence of Sarcocystis spp. A meat inspection-based survey was conducted in ten abattoirs in Narok County, Kenya, and inspection for T. saginata cysticerci was limited to the Triceps brachii muscle. The apparent occurrence of the parasite was 5.4% (95% CI, 3.8, 7.6, n =573). Molecular confirmation of T. saginata was done via nested polymerase chain reaction targeting the mitochondrial 12S ribosomal RNA gene and restricted fragment length polymorphism. Sarcocystis species were identified using a multiplex polymerase chain reaction method targeting the 18S ribosomal RNA gene sequences and the mitochondrial cytochrome c oxidase subunit I gene. Of the 31 cystic lesions tested, 26/31 (83.9%) were confirmed to be T. saginata. Sarcocystis cruzi and S. hominis were detected in 8/31 (25.8%) and 1/31 (3.2%) of the cystic lesions, respectively. Co-infections of S. cruzi and T. saginata were found in 6/31 lesions (19.4%). The confirmation of bovine cysticercosis and S. hominis is suggestive of the presence of risky culinary and sanitation practices that facilitate transmission. This is the first report and molecular confirmation of Sarcocystis spp. in cattle in the country. The presence of both zoonotic S. hominis and pathogenic S. cruzi highlights an underexplored concern of veterinary and human health significance, warranting further epidemiological investigation.

Objective: To investigate the prevalence and epidemiological characteristics of taeniasis and cysticercosis among residents in Tibetan agricultural areas of Sichuan Province, so as to provide insights for the prevention and control of taeniasis and cysticercosis., Methods: From 2016 to 2022, Kangding City, Daocheng County, Derong County, Ruoergai County and Muli Tibetan Autonomous County were sampled from Tibetan agricultural areas of Ganzi Tibetan Autonomous Prefecture, Aba Tibetan and Qiang Autonomous Prefecture and Liangshan Yi Autonomous Prefecture in Sichuan Province, and 1 to 6 townships were sampled from each county (district), followed by 4 to 7 villages sampled from each township. Primary school children were sampled using a cluster sampling method, and permanent residents at ages of over 16 years were randomly sampled from each village. Participants' demographics, history of tapeworm excretion during the past year and clinical symptoms and signs of cysticercosis were collected through questionnaire surveys, and participants' stool and venous blood samples were collected. Taenia eggs were detected in stool samples using the direct smear method, and deworming was performed among taeniasis patients with areca nut-squash seeds. The tapeworm species were identified using a multiplex PCR assay, and serum specific IgG antibody against cysticercus was detected using enzyme-linked immunosorbent assay (ELISA)., Results: A total of 5 249 respondents participated in the questionnaire survey, including 603 respondents (11.5%) with a self-reported history of proglottids secretion during the past year. A total of 3 976 residents were subjected to stool examinations, and the detection of Taenia eggs was 6.5%. Of 258 participants undergoing deworming, there were 403 cases (94.2%) with excretions of Taenia worms or proglottids. The mean prevalence of taeniasis was 10.9% (439/4 043), and there were gender-, age- and region-specific prevalence rates of taeniasis (χ 2 = 36.73, 126.31 and 163.41, all P values < 0.05). Multiplex PCR assays detected 41 cases with T. solium infections (12.5%), 197 cases with T. saginata infections (59.9%) and 91 cases with T. asiatica infections (27.6%) among 329 patients undergoing deworming, and there were region-specific prevalence rates of T. solium , T. saginata and T. asiatica infections (χ 2 = 45.39, P < 0.05). In addition, the sero-prevalence of anti-cysticercus IgG antibody was 7.0% (345/4 933), and there were age- and region-specific sero-prevalence rates of anti-cysticercus IgG antibody (χ 2 = 13.49 and 51.76, both P values < 0.05)., Conclusions: Multiple Taenia species are prevalent in Tibetan agricultural areas of Sichuan Province and the sero-prevalence of anti-cysticercus antibody is high among residents. Monitoring and control of taeniasis and cysticercosis should be strengthened.

Taeniasis/cysticercosis complex caused by Taenia solium, is a serious public health problem and causes major economic losses to swine producers in developing countries in Asia, Africa and the Americas. Despite scarce epidemiological data, Guatemala is considered endemic for T. solium. A cross-sectional study was conducted in Azacualpa and Malpais, two villages in the department of Zacapa, to assess the prevalence of swine cysticercosis and associated factors. Between March and October 2019, 149 pigs were examined by tongue palpation and serum samples were then collected to detect antibodies by ab-ELISA, and necropsy was performed on pigs that were positive by tongue palpation and/or ab-ELISA, to assess parasite load. Pig owners were asked to fill out a questionnaire on factors related to pig husbandry and occurrence of swine cysticercosis. Pearson's chi-square test and multivariate analysis were used to measure the association between serological results and other variables (p < 0.05 was considered significant). The seroprevalence of swine cysticercosis was 13.4% (13/97, 95% C.I. 6.6%-20.2%) and 25% (13/52, 95% C.I. 13.2%-36.8%) in Azacualpa and Malpais, respectively, yielding an overall seroprevalence of 17.4% (26/149, 95% C.I. 11.4%-23.5%). Parasite loads ranged from 1 to over 23,000 metacestodes per carcass. No bivariate association was found between exposure variables and seropositivity. A positive diagnosis by tongue palpation increased the odds of finding pigs seropositive for cysticercosis by a factor of 16.1 in the multivariate analysis. Despite the high prevalence and parasite load of T. solium, risk factors associated with cysticercosis were not significant in this study., Competing Interests: Declaration of Competing Interest The authors declare that this research was conducted without any commercial or financial relationship that could be construed as a conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Models can be used to study and predict the impact of interventions aimed at controlling the spread of infectious agents, such as Taenia solium, a zoonotic parasite whose larval stage causes epilepsy and economic loss in many rural areas of the developing nations. To enhance the credibility of model estimates, calibration against observed data is necessary. However, this process may lead to a paradoxical dependence of model parameters on location-specific data, thus limiting the model's geographic transferability., Methods: In this study, we adopted a non-local model calibration approach to assess whether it can improve the spatial transferability of CystiAgent, our agent-based model of local-scale T. solium transmission. The calibration dataset for CystiAgent consisted of cross-sectional data on human taeniasis, pig cysticercosis and pig serology collected in eight villages in Northwest Peru. After calibration, the model was transferred to a second group of 21 destination villages in the same area without recalibrating its parameters. Model outputs were compared to pig serology data collected over a period of 2 years in the destination villages during a trial of T. solium control interventions, based on mass and spatially targeted human and pig treatments., Results: Considering the uncertainties associated with empirical data, the model produced simulated pre-intervention pig seroprevalences that were successfully validated against data collected in 81% of destination villages. Furthermore, the model outputs were able to reproduce validated pig seroincidence values in 76% of destination villages when compared to the data obtained after the interventions. The results demonstrate that the CystiAgent model, when calibrated using a non-local approach, can be successfully transferred without requiring additional calibration., Conclusions: This feature allows the model to simulate both baseline pre-intervention transmission conditions and the outcomes of control interventions across villages that form geographically homogeneous regions, providing a basis for developing large-scale models representing T. solium transmission at a regional level., (© 2023. The Author(s).)

Taenia saginata is a zoonotic tapeworm of humans with bovines as its intermediate host (bovine cysticercosis). Traditional meat inspection is the main measure to identify the larval stage in carcasses and prevent human infection, but has a notoriously low sensitivity, especially in low prevalence settings. The legislation in multiple African countries mandates an incision in both triceps brachii muscles to detect the parasite as part of the normal post-mortem inspection, but this has an economic cost and is not universally mandated in other countries. The primary aim of this study was to investigate the epidemiology of bovine cysticercosis at an export abattoir in South Africa and determine the validity and cost of the triceps incision. Risk factors were investigated, and the effect of additional heart incisions on the current inspection. Four incisions were made into the heart in addition to the normal post-mortem inspection in 3353 carcasses. The proportion of positive animals with and without the cardiac and triceps incisions were compared using McNemar's chi-square tests, while risk factors were assessed using binary logistic regression. The economic impact of the triceps incision was estimated using a stochastic economic cost model. Thirty-three positive carcasses were identified for an apparent prevalence of 0.98 % (95 %CI, 0.69-1.36 %), while the true prevalence was estimated at 6.6 % (95 %CI, 4.3-8.8 %). All cysts were confirmed as T. saginata on histopathology with 70 % (95 %CI, 53-83 %) located in the heart. The additional cardiac incisions resulted in the detection of significantly more cases compared to the normal inspection method prevalence of 0.72 % (95 %CI, 0.47-1.05 %; P < 0.001). The apparent prevalence of T. saginata when omitting the triceps incision was not significantly lower compared to the prevalence when included in the inspection (P = 0.480). External feedlots (OR= 4.17, 95 %CI: 2.04-8.54, P < 0.001) and older animals (OR=3.90, 95 %CI: 1.17-13.03, P = 0.027) were associated with a positive detection. The current median annual financial cost to the food business operator from the triceps incision was estimated at $30387 (95 %CI: $0-$130696), with the proportion of deboned meat exported identified as the most important factor affecting cost (Spearman's rho=0.853). The identification of risk factors could aid in the development of a more effective risk-based inspection system. The current inspection should be modified to increase exposure of the heart and remove the triceps incisions. The latter should especially be considered given the minimal contribution to cysticercosis detection, the unsupported requirement for its inclusion specifically in Africa, and its economic impact, especially as beef exports increase., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Taenia solium taeniasis/cysticercosis (TSTC) is a foodborne, zoonotic neglected tropical disease affecting predominately low- and middle-income countries. Humans are definitive hosts for T. solium, whereas pigs act as intermediate hosts. Taeniasis, i.e. intestinal infection with adult T. solium in the human host, occurs through ingestion of undercooked pork infected with the larval stage (porcine cysticercosis, PCC). Human cysticercosis occurs after humans ingest T. solium eggs, acting as accidental intermediate hosts. Migration of cysticerci to the human brain results in neurocysticercosis (NCC), manifesting in a variety of clinical symptoms, most notably epilepsy. NCC is the leading cause of acquired epilepsy cases in endemic areas. PCC results in reduced pork value because of condemnation or the risk of condemnation of the meat. Available serological diagnostic tests for porcine and human cysticercosis are characterized by low sensitivity and are not cost-effective. An effective vaccine for T. solium cysticercosis in pigs has been developed, although it is not yet commercially available in all endemic countries, and still no vaccine is available for use in humans. This primer highlights the recent development in the field of diagnostic tests and vaccine production and explores possible strategies for future control and eradication of T. solium. In the absence of highly specific diagnostic tests and human vaccines, treatment of infected pigs and tapeworm carriers and prevention of disease transmission remain the principal means to interrupt the zoonotic cycle of T. solium in endemic countries., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Taenia solium is a parasite of public health concern, causing human taeniasis and cysticercosis. Two main genotypes have been identified: Asian and African-American. Although characterizing T. solium genotypes is crucial to understanding the genetic epidemiology of its diseases, not much is known about the differences between T. solium mitochondrial genomes from different genotypes. Also, little is known about whether genotypes are further subdivided. Therefore, this study aimed to identify a set of point mutations distributed throughout the T. solium mitochondrial genome that differentiate the African-American from the Asian genotype. Another objective was to identify whether T. solium main genotypes are further stratified., Methods: One Mexican and two Peruvian T. solium mitochondrial genomes were assembled using reads available in the NCBI Sequence Read Archive and the reference genome from China as a template. Mutations with respect to the Chinese reference were identified by multiple genome alignment. Jensen-Shannon and Grantham scores were computed for mutations in protein-coding genes to evaluate whether they affected protein function. Phylogenies by Bayesian inference and haplotype networks were constructed using cytochrome c oxidase subunit 1 and cytochrome b from these genomes and other isolates to infer phylogeographical relationships., Results: A set of 31 novel non-synonymous point mutations present in all genomes of the African-American genotype were identified. These mutations were distributed across the mitochondrial genome, differentiating the African-American from the Asian genotype. All occurred in non-conserved protein positions. Furthermore, the analysis suggested a stratification of the African-American genotypes into an East African and a West African sublineage., Conclusions: A novel set of 31 non-synonymous mutations differentiating the main T. solium genotypes was identified. None of these seem to be causing differences in mitochondrial protein function between parasites of the two genotypes. Furthermore, two sublineages within the African-American genotype are proposed for the first time. The presence of the East African sublineage in the Americas suggests an underestimated connection between East African and Latin American countries that might have arisen in the major slave trade between Portuguese Mozambique and the Americas. The results obtained here help to complete the molecular epidemiology of the parasite., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Taenia solium taeniasis/cysticercosis (TSTC) is a parasitic zoonotic disease that is endemic in several developing countries, causing serious public health and economic impacts. A cross-sectional study was conducted to assess knowledge, attitudes and practices (KAP) related to porcine cysticercosis (PCC) transmission, prevention and control among smallholder pig farmers in Kongwa and Songwe Districts in Tanzania. A semi-structured questionnaire was administered to 692 smallholder pig farmers from randomly selected households. STATA software version 17 was used to analyse quantitative data, summarize farmers' KAP about PCC and calculate performance scores. Nearly half (42%) of the respondents had little knowledge regarding PCC, only 17% of the respondents had good practices towards prevention/control of PCC and 72% had a positive attitude towards PCC- prevention/control measures. The majority (73%) of smallholder pig farmers admitted deworming their pigs regularly, whereas 76% reported deworming themselves and their family members regularly. Albendazole and ivermectin are the most commonly used medications for deworming people and pigs, respectively. According to the findings, the majority of smallholder pig farmers in Kongwa and Songwe Districts showed a good attitude towards PCC prevention/control measures but had limited knowledge of the PCC life cycle and control. In addition, only one in five farmers was engaged in good practices. The findings revealed further that farmers are engaged in risky behaviours that aid the spread and perpetuation of the T. solium parasite in the study area. It is recommended that farmers should be given proper health education on the T. solium transmission cycle and preventive/control practices to limit PCC transmission., Competing Interests: Declaration of Competing Interest There was no mention of a conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Several studies on Taenia solium taeniosis / cysticercosis (TSTC) have been conducted in Zambia. However, none has assessed community knowledge, attitudes and practices related to TSTC and epilepsy., Methods: A community-based cross-sectional study was conducted between November and December 2022. The design consisted of a questionnaire-based survey conducted in each of the 25 purposely selected villages in Chiparamba Rural Health Centre (RHC) catchment area in Chipata district of the Eastern Province., Results: A total of 588 participants comprising 259 (44%) males and 329 (56%) females with median age of 42 years (range 17 to 92 years) were interviewed. Awareness of the signs and symptoms of taeniosis and human cysticercosis (HCC), including transmission and prevention measures was very low. Whilst the majority had heard about epilepsy, they were not able to link HCC to epilepsy. Most participants were aware of cysticerci in pigs (PCC) including its predilection sites but were not aware of mode of transmission and prevention measures. The pork meat inspection by trained professionals was also not a common practice in the area. Risk perception of T. solium infections was thus very low. Overall knowledge, attitude and practice scores related to T. solium infections and to epilepsy were very low with median scores of 0.38 (IQR 0.25-0.54) for knowledge, 0.25 (0.25-0.50) for attitudes, and 0.31 (0.25-0.44) for practices. Males had better knowledge on TSTC (median = 0.42, p = 0.017, r = 0.098) and better practice scores (median = 0.38, p = < 0.001, r = 0.154) compared to females though the effect size was small. With regards to sanitation and hygiene washing with soap and water was reported by many but only few had a hand washing facility near their latrines., Conclusion: The study shows overall poor knowledge, attitudes and practices related to TSTC among the community of Chiparamba RHC in Chipata district of the Eastern Province of Zambia. This poses a serious challenge for control and elimination of T. solium infections and thus efforts to improve knowledge, attitudes and practices should be made using a One Health approach for the control and elimination of TSTC. Educational programs about TSTC transmission, signs and symptoms, prevention, management and control need to be scaled up in the study area and Zambia as a whole., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zulu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Tapeworm infections in humans are considered to be a significant public health menace. Despite its public health importance, the data on tapeworm infection remains fragmented and underutilised. The present study reviews the overall burden and distribution of taeniasis and cysticercosis caused by Taenia solium and Taenia saginata in India by conducting a systematic review of the scientific literature based on Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Data from 19 eligible articles were analysed and the prevalence of T. solium-associated taeniasis/cysticercosis was found to be 11.06% (95% confidence interval [CI] 6.856 to 16.119) and the prevalence of T. saginata-associated taeniasis was found to be 4.7% (95% CI 3.301 to 6.301). This systematic review and meta-analysis provides a comprehensive analysis of the available literature on tapeworm infections and assesses the burden of Taenia infection from India, identifying areas of high prevalence requiring active surveillance and public health interventions., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

Neurocysticercosis is recognized as an important health issue in the Malagasy population. To date, investigations into prevalence of infection with the causative agent, Taenia solium , in the parasite's natural animal intermediate hosts, have relied on serological methods which have been found to be non-specific. We determined the prevalence of porcine cysticercosis among pigs from a contiguous area of the Betafo and Mandoto administrative districts, Vakinankaratra Region, Madagascar. One hundred and four slaughter-weight pigs were examined by detailed necropsy examination including slicing of the heart, tongue, masseter muscles, diaphragm and carcase musculature. Thirty-seven animals (35.6%) were found infected with T. solium , representing one of the highest rates of infection ever reported, worldwide. These findings highlight the importance of T. solium in Madagascar and support the need for increased efforts to prevent the parasite's transmission to reduce its burden on the health of the Malagasy population.

Cysticercosis is a parasitic tissue infection caused by larval cysts of the tapeworm Taenia solium. These larval cysts infect brain, muscle, or other tissue, and are a major cause of adult-onset seizures in most low-income countries with tropical climate. Prevalence it's around 50 million people. Although cardiovascular system is not the most affected, this disease can also be associated with multiple and randomly distributed cysts in the subpericardium, subendocardium and myocardium in up to 25% of infected patients. Most cardiac cysticercosis' cases are asymptomatic, but it can manifest with ventricular arrhythmias and conduction disorders. Area Covered: The "Neglected Tropical Diseases and other Infectious Diseases affecting the Heart" (NET-Heart project) is an initiative by the Emerging Leaders group of the Interamerican Society of Cardiology to systematically review all these endemic conditions affecting the heart. A systematic review was conducted following preferred reporting items for systematic review and meta-analysis guidelines and including articles published in MEDLINE, ScienceDirect, PubMed and LILACS databases. A total of 41 papers were included in this review. Expert Opinion: In the areas of greatest prevalence, unhealthiness and poverty favor the development of this disease, which highlights the need to establish global health policies that reduce morbidity and mortality, economic losses of the affected population, and health costs related to hospitalizations for cardiovascular involvement. Authors provide an algorithm to evaluate the possibility of Cysticercosis' cardiovascular complications., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In Mexico, for the past 30 years, a continuous decrease in the incidence of clinical taeniosis/cysticercosis has been documented. This work aimed to determine the influence of improvement in socioeconomic conditions on the prevalence of Taenia solium in four endemic communities in northwestern Mexico. This study was carried out in two phases. First, documentary information (1989-2018) was collected about the prevalence of Theridion solium in the federal entity of Sinaloa State. Second, a pilot study was performed in four communities of Sinaloa, which had an endemic history of Taenia transmission. In each community, a risk factor questionnaire was applied, and serum and stool samples were collected for convenience in a non-probabilistic way. Anti-cysticercus antibodies and adult worm coproantigen were determined. The documentary analysis showed the incidence of taeniosis and cysticercosis to have decreased by 98 and 53%, respectively, while the human development index increased by 5% (1992-2017). Our data suggest that the risk of parasitic transmission is low, although female sex was a risk factor for reporting tremors or seizures (prevalence rate 2.1336, CI: 1.1821-3.8508) and background of tapeworm infection (prevalence rate 1.2893, CI: 0.9795-1.6972). No tapeworms or eggs were found while examining stool samples, but protozoa cysts were observed in four samples. Unexpectedly, only one of the 79 stool samples was positive for coproantigens. This positive result was confirmed in a second sample. However, the evaluation of a third sample was negative. No antibodies were found in human (n = 377) or pig (n = 69) samples. These data suggest parasite transmission has been interrupted and could be possibly associated with improving socioeconomic conditions. Further studies are needed to determine the real prevalence of zoonoses in Mexico., (© 2023 The Authors. Zoonoses and Public Health published by Wiley-VCH GmbH.)

The study describes the occurrence of cysticercosis in liver of 22 wild agoutis (Dasyprocta leporina) in the Brazilian Amazon. The phylogenetic analysis and microscopic characteristics of metacestodes in liver tissue sections, associated with the geographic distribution of the intermediate hosts indicated that a possibly novel Taenia sp. metacestode caused the parasitism. Additionally, two cases of hepatic co-infection by Taenia sp., Calodium sp. and Echinococcus oligarthra were also observed among the analyzed animals. The results point to the need for a better understanding of hepatotropic parasites among wild rodents in the Brazilian Amazon.

Coproantigen detection by enzyme-linked immunosorbent assay (coAg ELISA) is a vital tool for detecting and treating cases of Taenia solium taeniasis. However, the assay's procedures require costly materials and sophisticated equipment, which are typically inaccessible in rural settings where the disease is endemic. To overcome these barriers, we developed and evaluated a field-applicable coAg ELISA. The field coAg ELISA was developed and evaluated across four phases using known positive and negative stool samples collected from northern Peru. Phase I focused on field assay development, phase II on a small-scale performance evaluation, phase III on a large-scale evaluation, and phase IV on the use and reliability of a colorimetric scale card. All samples were processed using the field and standard assay procedures and compared using signal-to-noise ratios, correlation tests, performance characteristics, and agreement statistics where appropriate. The field coAg ELISA using reagents stored at -20°C and commercially available water and milk powder, and relying on spontaneous separation of the supernatant, had performance comparable to the standard assay. The field coAg ELISA was strongly correlated with the standard in both the small- and large-scale laboratory evaluation ( r  = 0.99 and r  = 0.98, respectively). Finally, the field assay had an almost perfect agreement between independent readers (kappa = 0.975) and between each reader and the spectrophotometer. The field coAg ELISA demonstrated performance comparable to the standard, providing a low-cost alternative to the standard assay for identifying cases of intestinal taeniasis in a low-resource setting., Competing Interests: The authors declare no conflict of interest.

Objectives: The lack of subnational mapping of the zoonotic cestode Taenia solium in endemic countries presents a major challenge to achieving intensified T. solium control milestones, as outlined in the "World Health Organization neglected tropical disease roadmap by 2030". We conducted a mapping study in Uganda, considered to be endemic, to identify subnational high-risk areas., Methods: T. solium prevalence data, adjusted for diagnostic sensitivity and specificity in a Bayesian framework, were identified through a systematic review. Spatial autocorrelation and interpolation techniques were used to transform demographic and health survey cluster-level sanitation and poverty indicators, overlaid onto a pig density map for Uganda into modelled  porcine cysticercosis (PCC) risk maps., Results: A total of 16 articles (n = 11 PCC and n = 5 human cysticercosis (HCC) and/or human taeniasis) were included in the final analysis. The observed HCC prevalence ranged from 0.01% to 6.0% (confidence interval range: 0.004-11.4%), whereas the adjusted PCC ranged from 0.3 to 93.9% (uncertainty interval range: 0-99.8%). There was substantial variation in the modelled  PCC risk factors and prevalence across Uganda and over time., Conclusion: The high PCC prevalence and moderate HCC exposure estimates indicate the need for urgent implementation of T. solium control efforts in Uganda., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Taeniasis/cysticercosis caused by tapeworms belonging to the genus Taenia, poses serious veterinary and public health problems, resulting in economic burden in endemic low-income countries worldwide. However, little epidemiological data exist on infection status among pigs in many areas in Tanzania. We conducted a cross-sectional survey in Rungwe District, Mbeya Region, Tanzania, to define the prevalence and risk factors associated with porcine cysticercosis transmission. One-hundred sixty-nine pigs from 152 households were examined for circulating taeniid antigens by cysticercosis antigen (Ag) enzyme-linked immunosorbent assay (ELISA). Agarose gel electrophoresis was used to differentially diagnose Taenia species-specific cysticerci DNA bands. Structured questionnaires were administered in the surveyed households to collect information on risk factors for porcine cysticercosis transmission. Sera from eleven household pigs tested positive for porcine cysticercosis in the Ag-ELISA with an apparent prevalence of 6.5 % (95 % C.I. 3.8-11.3 %) and estimated true prevalence of 6.1 % (95 % C.I. 3.3-10.9 %). DNA Gel electrophoresis confirmed that 100 % of cysticerci isolated amongst pigs slaughtered in the study area belonged to T. solium. Of the five surveyed wards, positive household pigs were from Bulyaga, Kiwira, and Mpuguso. Lack of knowledge on porcine cysticercosis among household members was found to be significantly associated with positivity of Taenia species antigen in pigs sera (OR = 7.742, p = 0.017). Our results show that porcine cysticercosis is prevalent in Rungwe. There is a definite need to establish control measures against this potential zoonosis to safeguard veterinary and public health in the Rungwe District., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Taenia solium is a tapeworm that causes taeniosis in humans and cysticercosis in humans and pigs. Within Eastern and Southern Africa (ESA), information on the presence of human taeniosis and cysticercosis seems scarce. This systematic review aimed to describe the current information available and gaps in the epidemiology of human T. solium infections in ESA., Methods/principle Findings: Scientific literature published between 1st January 2000 and 20th June 2022 in international databases [MEDLINE (Ovid), Embase (Ovid), Global Health (Ovid), Scopus (Elsevier), African Index Medicus (via WHO Global Index Medicus), and Open Grey] was systematically reviewed for ESA. The study area included 27 countries that make up the ESA region. Information on either taeniosis, cysticercosis or NCC was available for 16 of 27 countries within the region and a total of 113 reports were retained for the review. Most case reports for cysticercosis and NCC were from South Africa, while Tanzania had the most aggregated cysticercosis reports. Eleven countries reported on NCC with seven countries reporting data on NCC and epilepsy. Unconfirmed human T. solium taeniosis cases were reported in nine countries while two countries (Madagascar and Zambia) reported confirmed T. solium cases. The cysticercosis seroprevalence ranged between 0.7-40.8% on antigen (Ag) ELISA and between 13.1-45.3% on antibody (Ab) ELISA. Based on immunoblot tests the Ab seroprevalence was between 1.7-39.3%, while the proportion of NCC-suggestive lesions on brain CT scans was between 1.0-76% depending on the study population. The human taeniosis prevalence based on microscopy ranged between 0.1-14.7%. Based on Copro Ag-ELISA studies conducted in Kenya, Rwanda, Tanzania, and Zambia, the highest prevalence of 19.7% was reported in Kenya., Conclusions: Despite the public health and economic impact of T. solium in ESA, there are still large gaps in knowledge about the occurrence of the parasite, and the resulting One Health disease complex, and monitoring of T. solium taeniosis and cysticercosis is mostly not in place., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zulu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In Guatemala, neurocysticercosis (NCC) was first recognized in 1940; since then, cases of NCC have been reported in all Guatemalan departments. However, epidemiological studies on Taenia solium infections are scarce and most information remains unpublished. This study aims to provide evidence of T. solium infections as a public health problem in Guatemala. All information available, either published or unpublished, on T. solium infections in the country was compiled. Official data from the Ministry of Health for the period 2003-2019 were reviewed and analyzed, and all cases of T. solium infections were classified and counted. In total, 5246 cases of taeniasis and 454 cases of human cysticercosis were recorded. On the other hand, 44 studies were identified, mostly from local journals, which included 1951 cases of taeniasis, 2873 cases of human cysticercosis of which 543 were classified with complete diagnosis, and 2590 cases of porcine cysticercosis. Cases were classified by geographic region, patient sex, and Taenia species in taeniasis cases when information was available, and the departments with the highest number of taeniasis and cysticercosis cases were identified. Meanwhile, in Zacapa, a northeastern department of Guatemala with one the highest number of taeniasis cases, a young man diagnosed with a severe form of NCC and two cases of porcine cysticercosis (both confirmed by necropsy) were identified. Taken together, the data herein reported indicate that T. solium infections are a major health problem in Guatemala that needs to be addressed.

Parasitic infection is one of the many challenges facing livestock production globally. Cysticercosis tenuicollis is a common parasitic disease in domestic and wild ruminants (intermediate host) caused by the larval stage of Taenia hydatigena that primarily infects dogs (definitive host). Although genetic studies on this parasite exist, only a few describe the genetic variation of this parasite in Mongolia. Our aim was thus, to identify the mitochondrial differences in ovine isolates of Cysticercus tenuicollis entering China from Mongolia and comparison with existing Chinese isolates from sheep and goats based on the recently described PCR-RFLP method and mitochondrial genes of NADH dehydrogenase subunit 4 (nad4) and the NADH dehydrogenase subunit 5 (nad5). Sixty-nine isolates were collected during routine veterinary meat inspections from sheep that originated from Mongolia, at the modern slaughterhouses in Erenhot City, Inner Mongolia. Additional 114 cysticerci were also retrieved from sheep and goats from northern (Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, and Gansu Province), western (Tibet Autonomous Region), and southern (Jiangxi Province and Guangxi Province) China. The PCR-RFLP approach of the nad5 showed nine mitochondrial subclusters A1, A2, A3, A5, A8, A9, A10, A11, and B of T. hydatigena isolates from sheep and goats from Mongolia and China. Meanwhile, haplogroup A1 RFLP profile was more widespread than other variants. These data supplements existing information on the molecular epidemiology of T. hydatigena in China and Mongolia and demonstrate the occurrence of similar genetic population structures in both countries., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Taenia solium cysticercosis is a zoonotic disease that is endemic in many low- and middle-income countries where risk factors for disease transmission are present. The economic impact of cysticercosis on public health and on the pig production sector is not well known in many of those countries, including Burundi. This study aimed at estimating the burden of T. solium cysticercosis in Burundi including data on humans and pigs., Methods: Epidemiological and economic data were collected from literature up to July 30, 2021 and governmental and non-governmental agencies. Direct and indirect costs for neurocysticercosis (NCC)-associated epilepsy and losses due to porcine cysticercosis were estimated to assess the economic burden, while the health burden was estimated using zoonotic disability-adjusted life years (zDALYs). Different probability distributions (Uniform, Beta, Dirichlet and Gamma) were applied depending on the type of epidemiological parameter. Monte Carlo simulations and 100,000 iterations were used to calculate the 95% uncertainty interval (UI) for each parameter and perform sensitivity analyses., Results: In Burundi, 4.26 million USD (95% UI, 1,858,308-8,190,951) were estimated as economic impact due to T. solium cysticercosis in humans and pigs, of which 40.2% (95% UI, 10.3-75.1) of the total costs were due to NCC-associated epilepsy and 59.8% (95% UI, 24.9-89.7) of the losses due to porcine cysticercosis. The cost per NCC-associated epilepsy case was 72 USD (95% UI, 25-168), representing 30.8% of the GDP per capita in 2020. The probable incident cases and deaths for NCC-associated epilepsy were 9065 (95% UI, 2370-16,716) and 61 (95% UI, 16-114), respectively. More than 2 zDALYs (95% UI, 1.1-3.4) per thousand person-years was estimated, of which an average of 1.3 DALYs [0;0] (95% UI, 0.3-2.6) was due to NCC- associated epilepsy and 0.8 animal loss equivalents (ALEs) (95% UI, 0.3-1.5) due to porcine cysticercosis., Conclusions: This study provides evidence of a significant burden of T. solium cysticercosis for Burundi's population. We urge policy makers to use these evidence-based results and put T. solium cysticercosis on the public health agenda of the country. This study recommends urgent action to find solutions for integrated control strategies for T. solium cysticercosis in Burundi., (© 2022. The Author(s).)

Cysticercus tenuicollis is a larval stage of Taenia hydatigena resulting in cysticercosis, and responsible for enormous economic loses, especially in livestock production. Here, we planned to determine the prevalence and explore genetic variation of C. tenuicollis isolated from goats based on small subunit ribosomal RNA (rrnS) and cytochrome oxidase subunit 1 (cox1). To do this, samples were collected from different slaughter houses of municipal areas such as Bramhapalli slaughterhouse, Jubileeghat slaughterhouse and Mesuabazar slaughterhouse at Mymensingh sadar, and tentatively identified by morphological and morphometrical analysis. To study genetic variation, DNA was extracted from C. tenuicollis, and amplified rrnS and cox1 genes using specific primers, and were sequenced. Among 1372 examined animals, 177 (12.9%) were infected with C. tenuicollis. Cysts were recovered from peritoneum (7.9%), liver (4.4%) and urinary bladder (0.6%) of the infected animals. Females (18.9%) and adults (20.7%) were significantly more susceptible than male (8.8%) and young (9.3%), respectively. Genetic analysis defined 8 distinct rrnS genotypes and 9 unique cox1 haplotypes among 20 C. tenuicollis isolates. The nucleotide diversities were 0.00283 and 0.00434 for rrnS and cox1 genes, respectively. Neighbor joining (NJ) trees of rrnS and cox1 gene were constructed and the studied sequences were clustered with reference sequences of T. hydatigena with strong nodal support (100%). To compare Bangladeshi isolates, a median joining network was constructed with the population from other geographical regions and hosts. This led to a clustering pattern, but the clusters were not built with unique geographical regions or hosts. In conclusion, this is the first study that describes the genetic variation of T. hydatigena population and suggests the existence of host-specific variants. Therefore, it is fundamental to dispose infected viscera, restrict dog movement and proper management of slaughter house for the prevention and control of cysticercosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interests., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Taenia hydatigena is a non-zoonotic worm that has dogs and wild canids as definitive hosts. Its presence induces cross reactions in certain diagnostic tests for porcine cysticercosis caused by T. solium, the occurrence of which has a considerable public health and economic impact. In the Democratic Republic of the Congo (DR Congo), T. solium is considered endemic, however, the prevalence of T. hydatigena has not been estimated yet. The objective of the study was therefore to estimate the prevalence of T. hydatigena cysticercosis by serological and molecular diagnostic tools in pigs slaughtered in DR Congo. A total of 480 pigs slaughtered in 6 slaughter slabs in Kinshasa, DR Congo, were examined. The thoracal and abdominal cavity organs were inspected for cysts, which were analyzed using PCR-RFLP. Furthermore, 480 sera were collected, and analyzed for the presence of circulating Taenia spp. cysticercus antigens, using the B158/B60 Ag-ELISA. Upon inspection of the carcass, 41 cysts suspected to be metacestodes of Taenia spp. were collected, from the following viscera: spleen (24/41, 59%), liver (13/41, 32%), intestine (3/41, 7%) and lung (1/41, 2%). Molecular analyses revealed a T. hydatigena prevalence of 0.2% (95% CI: 0.0001-0.0116), based on a single lesion (1/480), taken from the spleen. Out of the 480 sera collected, the presence of circulating Taenia spp. cysticerci antigens was detected in 32 (6.7%; 95% CI: 4.5-11.2). The results of this study revealed that T. hydatigena is present in pigs sold in markets in the city of Kinshasa in DR Congo, albeit at a very low prevalence, thus the impact on the interpretation of the B158/B60 seems low in this setting. Detection of circulating antigens in porcine sera by Ag-ELISA, shows that pigs slaughtered in Kinshasa, DR Congo, were infected with viable cysticerci of Taenia spp. which in turn can infect humans., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest. Funders had no role in the study design, data collection, analysis or interpretation, drafting of the manuscript, or the decision to submit the manuscript for publication., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The pork tapeworm Taenia solium is a zoonotic food-borne parasite endemic in many developing countries causing human cysticercosis and taeniosis as well as porcine cysticercosis. It mainly affects the health of rural smallholder pig farmers and their communities, resulting in lower health status, reduced pork quality, and economic loss due to condemnation of pigs or low pricing of pork. This qualitative study aimed to identify key food related practices linked to consumption of pork at village level, of importance for transmission of taeniosis. We used an interpretivist-constructivist paradigm in a multiple case study of exploratory qualitative research design. Data was acquired through guided and probing interviews with 64 pork cooks, and 14 direct observations in four villages in a T. solium endemic area of Mbeya Region in the Southern Highlands of Tanzania. The study showed that the informants were members of communities of practice through their pork cooking practices, one community of practice for the restaurant cooks and one for the home cooks, learning, sharing, and distributing their cooking skills. Furthermore, the analysis showed that the pork cooks generally had some awareness of there being something undesirable in raw pork, but they had very diverse understandings of what it was, or of its potential harm. Major potential transmission points were identified in restaurants and in home kitchens. It appears that the pork cooks act according to socio-cultural and economic factors guiding them in their actions, including pressure from customers in restaurants, the family values of tradition in the home kitchens, and the culturally guided risk perception and appraisal. These practices might generate potential transmission points. Future research on interventions aimed at preventing the spread of T. solium taeniosis should recognise the importance of tradition and culture in risky food practices., Competing Interests: The authors have declared that no competing interests exist.

The pork tapeworm, Taenia solium, is the cause of a preventable zoonotic disease, cysticercosis, affecting both pigs and humans. Continued endemic transmission of T. solium is a major contributor of epilepsy and other neurologic morbidity, and the source of important economic losses, in many rural areas of developing countries. Simulation modelling can play an important role in aiding the design and evaluation of strategies to control or even eliminate transmission of the parasite. In this paper, we present a new agent based model of local-scale T. solium transmission and a new, non-local, approach to the model calibration to fit model outputs to observed human taeniasis and pig cysticercosis prevalence simultaneously for several endemic villages. The model fully describes all relevant aspects of T. solium transmission, including the processes of pig and human infection, the spatial distribution of human and pig populations, the production of pork for human consumption, and the movement of humans and pigs in and out in several endemic villages of the northwest of Peru. Despite the high level of uncertainty associated with the empirical measurements of epidemiological data associated with T. solium, the non-local calibrated model parametrization reproduces the observed prevalences with an acceptable precision. It does so not only for the villages used to calibrate the model, but also for villages not included in the calibration process. This important finding demonstrates that the model, including its calibrated parametrization, can be successfully transferred within an endemic region. This will enable future studies to inform the design and optimization of T. solium control interventions in villages where the calibration may be prevented by the limited amount of empirical data, expanding the possible applications to a wider range of settings compared to previous models., Competing Interests: The authors have declared that no competing interests exist.

Henan Province is one of the provinces where taeniasis and cysticercosis were historically highly prevalent, and Taenia solium is the dominant species of tapeworm. Following the concerted efforts since 1970s, the prevalence of human taeniasis and cysticercosis has been maintained at a low level in Henan Province, which facilitates the national taeniasis and cysticercosis elimination program in China. Following the implementation of the policy of aeniasis and cysticercosis elimination and classified guidance, a great success has been achieved in aeniasis and cysticercosis control in Henan Province. With continuous promotion of the opening-up policy and the Belt and Road Initiative, there are still challenges in taeniasis and cysticercosis control. This review summarizes the control progress of taeniasis and cysticercosis and proposes the challenges of taeniasis and cysticercosis control in Henan Province.

Infection by Taenia solium poses a major burden across endemic countries. The World Health Organization (WHO) 2021-2030 Neglected Tropical Diseases roadmap has proposed that 30% of endemic countries achieve intensified T. solium control in hyperendemic areas by 2030. Understanding geographical variation in age-prevalence profiles and force-of-infection (FoI) estimates will inform intervention designs across settings. Human taeniasis (HTT) and human cysticercosis (HCC) age-prevalence data from 16 studies in Latin America, Africa, and Asia were extracted through a systematic review. Catalytic models, incorporating diagnostic performance uncertainty, were fitted to the data using Bayesian methods, to estimate rates of antibody (Ab)-seroconversion, infection acquisition and Ab-seroreversion or infection loss. HCC FoI and Ab-seroreversion rates were also estimated across 23 departments in Colombia from 28,100 individuals. Across settings, there was extensive variation in all-ages seroprevalence. Evidence for Ab-seroreversion or infection loss was found in most settings for both HTT and HCC and for HCC Ab-seroreversion in Colombia. The average duration until humans became Ab-seropositive/infected decreased as all-age (sero)prevalence increased. There was no clear relationship between the average duration humans remain Ab-seropositive and all-age seroprevalence. Marked geographical heterogeneity in T. solium transmission rates indicate the need for setting-specific intervention strategies to achieve the WHO goals., Competing Interests: MD, PW, WH, CW, VS, AF, ZC, AE, MW, MB No competing interests declared, (© 2022, Dixon et al.)

Taenia saginata taeniosis and bovine cysticercosis are prevalent in Ethiopia, however, data on the knowledge/attitude, and practice (KAP) of the community and meat industry workers in this regard is scarce. The present study aimed to investigate the KAP of the community and meat industry workers about T. saginata taeniosis/cysticercosis in Jimma and Ambo towns of Ethiopia. A cross-sectional KAP survey was performed on 293 community members selected using multistage random sampling and 97 meat industry workers from the two study towns. A questionnaire was constructed to collect sociodemographic variables, knowledge/attitudes about taeniosis/cysticercosis, raw meat consumption, latrine usage, and taeniosis treatment practices. Mixed effect (generalized) linear models were used to assess the association of self-reported taeniosis as well as the KAP scores with the demographic variables. The predicted proportion of self-reported taeniosis was 54% and 75% for Jimma and 44% and 70% for Ambo community and meat industry workers, respectively. The odds of self-reported taeniosis was higher for men (OR adj , 1.68, 95%CI, 0.97-2.93), and elementary/illiterate (OR adj , 1.46, 95%CI, 0.75-2.86) and high school education level (OR adj , 2.65, 95%CI, 1.45-4.93) compared to their counterparts. Most of the community members and the vast majority of the meat industry workers were knowledgeable about taeniosis but less conscious about cysticercosis. The knowledge/attitude score of the community was positively associated with the Jimma community (β adj = 1.20, 95%CI 0.60-1.80), age (β adj =0.03 points higher per year, 95%CI 0.00- 0.04), and men (β adj = 1.20, 95%CI 0.64-1.76), while it was lower in elementary education/illiterate (β adj = -1.60, 95%CI -2.31 to -0.95) and secondary/high school (β adj = -0.83, 95%CI -1.46 to -0.23). The good practice scores of the community within both towns were negatively associated with increasing age (β adj =-0.01 per year, 95%CI, -0.02 to 0.00), elementary/illiterate (β adj = -0.60, 95%CI -1.01 to -0.19) and secondary/high school education (β adj = -0.09, 95%CI -0.45 to -0.28), and urban community (β adj = -0.47 95%CI, -0.82 to -0.12), while protestant/other (β adj = 0.76, 95%CI 0.36 1.16) religion had higher scores compared to Orthodox religion. In conclusion, the predicted self-reported taeniosis proportion was moderately high, and the knowledge/attitude was substantial whereas, the practice was inferior. The association between the knowledge/attitude score and practice score was very weak. Therefore, public education to improve hygienic practices, risky culinary habits, taeniosis treatment, and backyard slaughtering were suggested., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Taenia hydatigena is a widespread tapeworm of canids (primarily dogs) that causes cysticercosis in ruminants (domestic and wild) and manifests as depression and weakness secondary to various hepatic damages and sometimes mortality in young animals, although, commonly encountered cases are asymptomatic. In most taeniids, genetic polymorphism has been found to impact host preferences, distribution, disease epidemiology and management. Recently, we identified two main mitochondrial lineages of T. hydatigena in China, and here, we examined the mitochondrial nad4-nad5 genes of T. hydatigena from China, Nigeria, Pakistan and Sudan to assess the intraspecies variation of isolates from these countries and also the distribution of the distinct mitochondrial groups. In addition to China, haplogroup B variant was found in Pakistan, while haplogroup A demonstrated a widespread distribution. We then designed a PCR-restriction fragment length polymorphism (PCR-RFLP) assay using XmiI (AccI) and RsaI (AfaI) restriction enzymes to differentiate members of both haplogroups. This result provides more molecular evidence supporting the existence of distinct mitochondrial variants of T. hydatigena. The epidemiological significance of these different mitochondrial groups remains to be explored further. The current PCR-RFLP assay offers a useful molecular approach for investigating the genetic population structure of T. hydatigena in enzootic regions and in identifying/discriminating the different mitochondrial groups (haplogroups A and B)., (© 2021 Wiley-VCH GmbH.)

Neurocysticercosis (NCC) is a leading cause of preventable epilepsy in lower- and upper- middle-income countries (LMICs/UMICs). NCC is a human-to-human transmitted disease caused by ingestion of Taenia solium eggs from a Taenia carrier. T. solium infection control is the key to reduce NCC incidence. This systematic review aims to identify T. solium control programs that can provide frameworks for endemic areas to prevent NCC-related epilepsy. A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Cochrane Library databases in March 2021. After title and abstract review, full texts were screened for qualitative analysis. Additional articles were identified via citation search. Of 1322 total results, 34 unique studies were included. Six major intervention types were identified: national policy (8.8%), community sanitation improvement (8.8%), health education (8.8%), mass drug administration (29.4%), pig vaccination and treatment (32.4%), and combined human and pig treatment (11.8%). Overall, 28 (82.4%) studies reported decreased cysticercosis prevalence following the intervention. Only health education and combined human and pig treatment were effective in all selected studies. NCC causes preventable epilepsy in LMICs/UMICs and its incidence can be reduced through T. solium control. Most interventions that disrupt the T. solium transmission cycle are effective. Long-term sustained results require comprehensive programs, ongoing surveillance, and collaborative effort among multisectoral agencies.

Taenia solium cysticercosis is a potentially eradicable neglected zoonotic disease with public health importance. The genetic lineages of T. solium in Asia and Africa/America are distinct and the genetic composition of the parasite was found to influence the clinical symptoms in patients with cysticercosis. In the present study, the Cysticerci collected from pigs of two southern states of India (Karnataka and Andhra Pradesh) were genetically characterized based on mitochondrial (COX 1 and Cyt b) and ribosomal (ITS-1 and TBR) DNA markers. The study confirms the existence of two mitochondrial lineages of the parasite as Asian and African/American. Cytochrome oxidase 1 (COX 1) based analysis revealed the existence of two sub-lineages of the parasite within the Asian lineage based on the polymorphism at 994 position as 994A/G. In India, both the sub-lineages were identified and genetic divergence among different Indian isolates was evident. Further, the sequence analysis of Cytochrome B (Cyt b) revealed the existence of six sub-lineages of T. solium in India as 69T/69G, 97A/97G as well as 264T/264C. The analysis of nucleotide sequence of large subunit ribosomal DNA (TBR) revealed the existence of two sub-lineages in India based on the deletion of a nucleotide at 624 th position. The cysts collected in the present study were more closely related to those of China and Indonesia than with other Indian isolates. Further, the sequence analysis did not indicate the presence of Taenia asiatica in the examined pigs and African/American lineages of T. solium. The results of the present study help to better understand the genetic diversity of T. solium in India., (© 2021 Wiley-VCH GmbH.)

Background: Taenia solium cysticercosis/taeniasis (TSCT) is reported to be endemic in pig producing areas around the world, causing significant disease burden and economic losses., Methods: This cross-sectional study aimed at assessing Knowledge, Attitudes and Practices (KAP) regarding TSCT in four districts, namely Mbulu, Mpwapwa, Mbinga, and Rungwe in Tanzania. Data on KAP were collected through questionnaire-based interviews and household infrastructure observations., Results: Knowledge about porcine cysticercosis was good, particularly among pig keepers across the districts. Many participants had heard about the pork tapeworm (T. solium taeniasis), and the knowledge about signs/symptoms and treatment was fair, but the means of transmission and prevention measures were often unknown. Whilst most participants were familiar with epilepsy, no one knew anything about human cysticercosis and the link between cysticercosis and epileptic seizures. A similar trend is reflected through the attitudes toward the low risk perception of cysticercosis infection. Not surprisingly, the risk perception of the infection with the pork tapeworm was low too. Many participants reported not washing their hands before eating or after using the toilet which highlights potential risks for the development of human cysticercosis. Albeit nearly every participant reported using the toilet always, household observations revealed that toilets were either lacking or had no complete walls. Generally, household observations revealed a discrepancy between questionnaire answers on the one hand and the availability of toilet and handwashing facilities and the confinement of pigs on the other hand., Conclusion: This study demonstrates knowledge gaps and adverse practices which may hinder and/or slow down the control/elimination of T. solium in endemic countries. The study results are also useful for appropriate designing of TSCT health interventions that need to be planned carefully, taking into account the local context and designing TSCT in partnership with the local communities from the beginning to the end applying a One Health approach to allow the possible sustained and best impacts., (© 2022. The Author(s).)

Introduction: The Taenia solium tapeworm is responsible for cysticercosis, a neglected tropical disease presenting as larvae in the body of a host following taenia egg ingestion. Neurocysticercosis (NCC), the name of the disease when it affects the human central nervous system, is a major cause of epilepsy in developing countries, and can also cause intracranial hypertension, hydrocephalus and death. Simulation models can help identify the most cost-effective interventions before their implementation. Modelling NCC should enable the comparison of a broad range of interventions, from treatment of human taeniasis (presence of an adult taenia worm in the human intestine) to NCC mitigation. It also allows a focus on the actual impact of the disease, rather than using proxies as is the case for other models., Methods: This agent-based model is the first model that simulates human NCC and associated pathologies. It uses the output of another model, CystiAgent, which simulates the evolution of pig cysticercosis and human taeniasis, adding human and cyst agents, including a model of cyst location and stage, human symptoms, and treatment. CystiHuman also accounts for delays in the appearance of NCC-related symptoms. It comprises three modules detailing cyst development, seizure probability and timing, and intracranial hypertension/hydrocephalus, respectively. It has been implemented in Java MASON and calibrated in three endemic villages in Peru, then applied to another village (Rica Playa) to compare simulation results with field data in that village., Results and Discussion: Despite limitations in available field data, parameter values found through calibration are plausible and simulated outcomes in Rica Playa are close to actual values for NCC prevalence and the way it increases with age and cases with single lesions. Initial simulations further suggest that short-term interventions followed by a rapid increase in taeniasis prevalence back to original levels may have limited impacts on NCC prevalence., Competing Interests: The authors have declared that no competing interests exist.

Background: Taenia solium typically affects resource-poor communities where pigs are allowed to roam freely, and sanitation and hygiene levels are suboptimal. Sustainable, long-term strategies are urgently needed to control the disease. Geographically targeted interventions, i.e. screening or treatment of taeniosis among people living near infected pigs (defined as ring screening and ring treatment, respectively), have been shown to be effective control options in Peru. However, these results might not be directly generalizable to sub-Saharan African settings. Pig movements play a vital role in the transmission and, consequently, the success of ring interventions against T. solium. The aim of the present study was to explore roaming patterns of pigs in T. solium endemic communities in Zambia as a first step toward evaluating whether ring interventions should be considered as a treatment option in Zambia., Methods: In total, 48 free-roaming pigs in two rural neighborhoods in the Eastern Province of Zambia were tracked using a Global Positioning System (GPS) receiver. Tracking took place in April (end of the rainy season) 2019 and October (end of the dry season) 2019. The number of revisitations and the time spent within rings of different radii (50, 100 and 250 m) around the coordinates of each pig owner's household were calculated for each pig., Results: The total tracking time for 43 pigs in the final analysis set ranged between 43 and 94 h. Pigs spent a median of 31% and 13% of the tracked time outside the 50- and 100-m radius, respectively, although large variations were observed between pigs. Overall, 25 pigs (58%) went outside the 250-m ring at least once, and individual excursions lasting up to 16 h were observed. In the dry season, 17 out of 23 pigs went outside the 250-m radius compared to only eight out of 20 pigs in the rainy season (P = 0.014)., Conclusions: In our study sites in Zambia, the majority of pigs spent most of their time within 50 or 100 m of their owner's home, and these results are comparable with those on Peruvian pigs. Both radii could therefore be considered reasonable options in future ring interventions., (© 2022. The Author(s).)

Background: Infections with the tapeworm Taenia solium (taeniosis and cysticercosis) are Neglected Tropical Diseases (NTD) highly endemic in Madagascar. These infections are however underdiagnosed, underreported and their burden at the community level remains unknown especially in rural remote settings. This study aims at assessing the prevalence of T. solium infections and associated risk factors in twelve remote villages surrounding Ranomafana National Park (RNP), Ifanadiana District, Madagascar., Methodology: A community based cross-sectional survey was conducted in June 2016. Stool and serum samples were collected from participants. Tapeworm carriers were identified by stool examination. Taenia species and T. solium genotypes were characterised by PCR and sequencing of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. Detection of specific anti-cysticercal antibodies (IgG) or circulating cysticercal antigens was performed by ELISA or EITB/Western blot assays., Principal Findings: Of the 459 participants with paired stool and blood samples included ten participants from seven distinct villages harbored Taenia spp. eggs in their stools samples DNA sequencing of the cox1 gene revealed a majority of T. solium Asian genotype (9/10) carriage. The overall seroprevalences of anti-cysticercal IgGs detected by ELISA and EITB were quite similar (27.5% and 29.8% respectively). A prevalence rate of 12.4% of circulating cysticercal antigens was observed reflecting cysticercosis with viable cysts. Open defecation (Odds Ratio, OR = 1.5, 95% CI: 1.0-2.3) and promiscuity with households of more than 4 people (OR = 1.9, 95% CI: 1.1-3.1) seem to be the main risk factors associated with anticysticercal antibodies detection. Being over 15 years of age would be a risk factor associated with an active cysticercosis (OR = 1.6, 95% CI: 1.0-2.7). Females (OR = 0.5, 95% CI: 0.3-0.9) and use of river as house water source (OR = 0.3, 95% CI: 0.1-1.5) were less likely to have cysticercosis with viable cysts., Conclusions/significance: This study indicates a high exposure of the investigated population to T. solium infections with a high prevalence of cysticercosis with viable cysts. These data can be useful to strengthen public health interventions in these remote settings., Competing Interests: The authors have declared that no competing interests exist. Authors Emma Rakotomalala, Jaydon Kiernan, and Koeun Choi were unavailable to confirm their authorship contributions. On their behalf, the corresponding author has reported their contributions to the best of their knowledge.

Taenia solium cysticercosis is the most common cause of acquired epilepsy in pig-raising and pork-consuming parts of Africa, Latin America, and Asia. This review aimed to systematically compile and synthesize data on the epidemiology of porcine cysticercosis in the Eastern and Southern Africa (ESA) region. Comprehensive searching strategies were employed to retrieve the studies published or reported between January 1,1997 and March 1, 2021, from Pub Med, Hinari, and Google Scholar databases and search platforms. The identified studies that met the inclusion criteria were then appraised for methodological quality. Finally, 44 studies obtained from nine countries were selected and included in this review. Relevant data were extracted using standardized templates for qualitative synthesis and meta-analysis. The overall pooled prevalence estimate of porcine cysticercosis in the ESA region was 17% (95% CI: 14-20%). The prevalence level between and within countries showed high variability. The pooled estimate showed high heterogeneity among the reports (the inverse variance index value (I 2 ) of 98.99%, p < 0.05). The meta-analysis sub-grouped by the type of diagnostic test showed the pooled prevalence estimate of 27% (95% CI: 9-50) by carcass dissection; 23% (95% CI: 14-33) by Antibody-based immunodiagnostic techniques; 23% (95% CI: 18-29) by antigen detecting (Ag)-ELISA, 12% (95% CI: 7-18) by meat inspection, and 9% (95% CI: 7-11) by lingual examination. The meta-analysis sub-grouped by region showed a relatively higher pooled prevalence estimate for the Southern region 22% (95% CI: 15-30) compared to 13% (95% CI: 11-15) in the Eastern region. The highest country-based pooled prevalence was obtained from South Africa (33%, 95% CI: 20-48) and Zambia (22%, 95% CI: 16-29), whereas the lowest pooled prevalence was identified in Madagascar (5%, 95% CI: 4-5) and Rwanda (7%, 95% CI: 6-8). The lack of latrine, traditional pig husbandry practices, unprotected water sources, and increase in age were identified as significant risk factors for the occurrence of porcine cysticercosis in the pooled studies. The findings of this review will provide context-specific input to prioritize the possible intervention programs for T. solium control in the ESA region. More sensitive and specific test-based prevalence estimates, detailed risk factor investigations, and financial losses analysis are needed to establish feasible control strategies., Systematic Review Registration: http://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42021238931., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gulelat, Eguale, Kebede, Aleme, Fèvre and Cook.)

Taenia solium is an important cause of acquired epilepsy worldwide and remains endemic in Asia, Africa, and Latin America. Transmission of this parasite is still poorly understood despite the design of infection experiments to improve our knowledge of the disease, with estimates for critical epidemiological parameters, such as the probability of human-to-pig infection after exposure to eggs, still lacking. In this paper, a systematic review was carried out and eight pig infection experiments were analyzed to describe the probability of developing cysts. These experiments included different pathways of inoculation: with ingestion of proglottids, eggs, and beetles that ingested eggs, and direct injection of activated oncospheres into the carotid artery. In these experiments, different infective doses were used, and the numbers of viable and degenerated cysts in the body and brain of each pig were registered. Five alternative dose-response models (exponential, logistic, log-logistic, and exact and approximate beta-Poisson) were assessed for their accuracy in describing the observed probabilities of cyst development as a function of the inoculation dose. Dose-response models were developed separately for the presence of three types of cysts (any, viable only, and cysts in the brain) and considered for each of the four inoculation methods ("Proglottids", "Eggs", "Beetles" and "Carotid"). The exact beta-Poisson model best fit the data for the three types of cysts and all relevant exposure pathways. However, observations for some exposure pathways were too scarce to reliably define a dose-response curve with any model. A wide enough range of doses and sufficient sample sizes was only found for the "Eggs" pathway and a merged "Oral" pathway combining the "Proglottids", "Eggs" and "Beetles" pathways. Estimated parameter values from this model suggest that a low infective dose is sufficient to result in a 50% probability for the development of any cyst or for viable cyst infections. Although this is a preliminary model reliant on a limited dataset, the parameters described in this manuscript should contribute to the design of future experimental infections related to T. solium transmission, as well as the parameterization of simulation models of transmission aimed at informing control., Competing Interests: The authors have declared that no competing interests exist.

Information on age-based Taenia solium taeniasis prevalence is crucial for control of cysticercosis. T. solium taeniasis prevalence was determined for a village in Liangshan Prefecture, Sichuan Province, China that was co-endemic for T. solium, Taenia saginata asiatica , and Taenia saginata . Individuals who were Taenia egg-positive by stool microscopy and/or expelled tapeworms or proglottids post-treatment were diagnosed as having taeniasis. Infecting species was identified via multiplex PCR on tapeworm specimens or coproPCR followed by sequencing. In addition, initial stool samples from 10 children with taeniasis suspected of having spontaneous expulsion of tapeworms within the period between diagnosis and treatment were subject to species confirmation via coproPCR and sequencing. Of the 389 study subjects, 194 (49.9%) were diagnosed with taeniasis. Children (< 16 years of age) had a higher T. solium taeniasis prevalence (8.8%) than older individuals (2.5%) (P = 0.0127). Molecular analysis of initial stool samples from 7 of 10 children suspected of spontaneously passing tapeworms indicated 6 infections due to T. solium and 1 infection due to T. saginata . This study found that young children had a higher T. solium taeniasis prevalence than older individuals, providing additional support for the belief that adult T. solium likely has a relatively short lifespan compared to other Taenia species with human definitive hosts.