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This article analyzes data from scientific publications (mainly reviews) concerning the link between human neurocysticercosis and epilepsy. Along with data from our own studies on experimental hippocampal sclerosis induced by a Taenia crassiceps metacestode factor in mice, it explores the connection between mechanisms that likely favor the development of epilepsy in cases of human neurocysticercosis. The data from both sources suggest the idea that the T. solium metacestode factor causes hippocampal sclerosis and later epilepsy in humans with neurocysticercosis.

Cystic Echinococcosis (CE) is a neglected zoonotic disease caused by the metacestode form of Echinococcus granulosus sensu lato. Non-invasive imaging techniques, especially ultrasound, are primarily used for CE diagnosis. MicroRNAs (miRNAs) are small, non-coding RNA molecules that act as post-transcriptional regulators in various biological processes. After identification of parasite-derived miRNAs, these miRNAs are considered to be potential biomarkers for diagnosis and follow-up. The focus of this research is to compare the expression profiles of certain parasite-derived miRNAs in CE patients with active and inactive cysts as well as healthy controls. Parasite-derived miRNAs, egr-let-7-5p, egr-miR-71a-5p, and egr-miR-9-5p, of inactive CE patients were found to be differentially expressed with 3.74-, 2.72-, and 20.78-fold change (p

Cestode infestations in animals are the most important parasite of livestock and humans because most of these parasites are zoonotic causing cysticercosis and hydatidosis in man and it causes economic and production losses in livestock. Diagnosis of Taenia Spp by microscopic observation lack sensitivity and specificity and detection by enzyme-linked immunosorbent assay (ELISA) technique form cross-reaction. The molecular diagnostic can be best to detect in adult and larval stage in definitive and intermediate host based on the amplification of deoxyribonucleic acid (DNA) of target gene with the primer using a different technique of polymerase chain reaction (PCR) such as multiplex PCR. Conventional PCR, real-time PCR, nested PCR, and PCR-restriction fragment length polymorphism (RFLP) are highly sensitive for the diagnosis of cestode and metacestode. Those diagnoses are used for differentiation of Taenia species and differentiation of Taenia and Echinococcus species. As compared to other diagnostic techniques most molecular methods have higher sensitivity and specificity but due to the relatively higher cost, few are commercially available. Most of the molecular diagnostic tests developed to date are generally applicable for laboratory research purposes. The developments in the genomic and proteomic analysis should be used for further understanding of parasite-animal host interaction to find additional targets for diagnosis.

PURPOSE OF REVIEW Infection with the larval (metacestode) stage of Echinococcus multilocularis causes alveolar echinococcosis (AE), a serious hepatic disorder. The parasite has increased its infection extensity in wildlife and domestic dogs, mainly due to urbanization and spatial extension of wildlife hosts in Europe, Asia as well as North America, resulting in emerging infection risk for humans. RECENT FINDINGS In hyperendemic areas such as Kyrgyzstan and China, ecological and socioeconomic changes have been associated with the unpredictable increase of AE cases. In North America, the appearance of the European-like genotype is of concern. In Europe, the annual increase of human case numbers reached a plateau even in hyperendemic situations. Therefore, we conclude that most of the exposed individuals are resistant to parasite invasion and/or to disease development. Thus, AE develops in a few healthy individuals, but preferentially in immunosuppressed patients. SUMMARY In the future, improved diagnostic strategies will allow more precise estimations of transmission routes including the role of food, water and direct dog contact, which should yield improved public health recommendations. Finally, understanding protective innate and acquired immune mechanisms as well as parasite-driven immune-evasion processes will be essential to develop curative therapies in nonoperable patients and, futuristically, appropriate vaccines.

Echinococcal disease is caused by infection with the metacestode stage of the tapeworm Echinococcus,which belongs to the family Taeniidae. Four species of Echinococcus produce infection in humans; E.granulosus and E. multilocularis are the commonest, causing cystic echinococcosis (CE) and alveolarechinococcosis (AE), respectively. The clinical features of infection due to E. granulosus and E. multilocularisdiffered from each other. The two other species, E. vogeli and E. oligarthrus, cause polycysticechinococcosis but have only rarely had been ass-ociated with man. Surgery is still the gold standardtreatment, chemotherapy is retracted to some patient, because yields inconsistent result. The study was carriedout up on 16 male patients with single giant uncomplicated lung hydatid admitted to Kobry El Kobba MilitaryCampus. The patients was randomly divided into two groups, GI included 8 patients, of whom 6 patients withright lung lesion and 2 with left lung lesion. One of the 6 patients with right side liver lesion was treated bycystotomy, after aspiration of cyst fluid and enucleation of germinal layer and de-roofing the cyst. G II included8 patients, 4 patients with left side lesion and 4 with right side lesion and 2 patients had both lung andThe most diagnostic tool was chest radiography and CT. Treatment included medical and surgical treatmentwas divided into conservative surgery and radical surgery. Both groups were treated by conservativesurgical method but the outcome in GI was better than in GII.

Background Cysticercosis caused by cysticercus tenuicollis is a metacestode infection that affects several species of ungulates. It is caused by the larval stage of Taenia hydatigena, an intestinal tapeworm in dogs and wild canids. In the intermediate host, the mature cysticerci are usually found in the omentum, mesentery, and peritoneum, and less frequently in the pleura and pericardium. The migrating larvae can be found mostly in the liver parenchyma causing traumatic hepatitis in young animals. Most infections are chronic and asymptomatic, and are diagnosed at the abattoir. The acute form of infection is unusual in sheep and reports of death in lambs are rare. Methods In March 2018, fifteen female lambs presented anorexia, weakness, lethargy, and death secondary to acute visceral cysticercosis. Twelve of them underwent hepatic ultrasonography. Examinations were performed on standing or left lateral recumbent animals. Results Livers of affected animals presented rounded margins and a thickened, irregular and hyperechoic surface. Hepatic parenchyma appeared to be wholly or partially affected by lesions characterized by heterogeneous areas crossed by numerous, irregular, anechoic tracts ranging from 1 to 2 cm in length and 0.1 to 0.2 cm in width. Superficial and intraparenchymal cystic structures were also visualized. The presence of lesions was confirmed by anatomopathological examination, and T. hydatigena cysticerci was identified by morphological and molecular characterization of isolates. Conclusions Our results highlighted that hepatic ultrasonography is effective for an intra-vitam diagnosis of acute cysticercosis in lambs.

Susceptibility to Echinococcus multilocularis infection considerably varies among intermediate (mostly rodents) and dead-end host species (e.g. humans and pig), in particular regarding intestinal oncosphere invasion and subsequent hepatic metacestode development. Wistar rats are highly resistant to infection and subsequent diseases upon oral inoculation with E. multilocularis eggs, however, after immunosuppressive treatment with dexamethasone, rats become susceptible. To address the role of the cellular innate immunity, Wistar rats were individually or combined depleted of natural killer (NK) cells, macrophages (MΦ) and granulocytes (polymorphonuclear cells, PMN) prior to E. multilocularis egg inoculation. Although NK cell and MΦ depletion did not alter the resistance status of rats, the majority of PMN-depleted animals developed liver metacestodes within 10 weeks, indicating that PMN are key players in preventing oncosphere migration and/or development in Wistar rats. In vitro studies indicated that resistance is not caused by neutrophil reactive oxygen species or NETosis. Also, light microscopical examinations of the small intestine showed that oral inoculation of E. multilocularis eggs does not elicit a mucosal neutrophil response, suggesting that the interaction of oncospheres and neutrophils may occur after the former have entered the peripheral blood. We suggest to consider granulocytes as mediators of resistance in more resistant species, such as humans.

Alveolar echinococcosis (AE) is a life-threatening parasitic disease caused by the zoonotic cestode Echinococcus multilocularis. Our goals were to confirm infection, identify species, and analyze biogeographical origin of metacestode tissues from a suspected human AE case in Saskatchewan, Canada. We conducted polymerase chain reaction (PCR) targeting the nad1 mitochondrial gene for E. multilocularis and the rrnS ribosomal RNA gene for E. granulosus and conducted haplotype analysis at the nad2 locus. Our analysis confirmed AE and indicated that sequences matched infected Saskatchewan coyotes and European E3/E4 haplotypes. The patient had no travel history outside North America. This suggests autochthonous transmission of a European-type strain.

Coenuriasis (also called coenurosis, gid or sturdy) is another neglected parasitic infection that is implicated in human clinical complications. It is a rare zoonotic infection with either Taeniamulticeps or T. serialis. The information available in the literature about human infection is scattered and sometimes argumentative.

The metacestode of Echinococcus multilocularis is the etiological agent of alveolar echinococcosis. The metacestode stage used for research is maintained in rodents by serial passages. In order to determine whether cryopreservation of E. multilocularis metacestodes would be suitable for long-term maintenance and replace serial passages, isolates of different geographic origin were cryopreserved in 1984–1986. The aim of the current study was to test the viability of cryopreserved isolates following long-term cryopreservation (up to 35 years) and to determine the phylogenetic clades these isolates belonged to. Cryopreserved isolates were tested for viability in vitro and in vivo in gerbils. In vitro results of 5 isolates indicated protoscolex survival in 13 of 17 experiments (76%) and metacestode survival in 5 of 12 (42%) in vivo experiments. In vivo results showed ‘abortive lesions’ in 13 of the 36 animals, 15 were negative and 8 harboured proliferating metacestode tissue containing protoscoleces. Genetic analysis confirmed the isolates belonged to European, Asian and North-American clades. In conclusion, the results of the current study indicate that metacestodes of E. multilocularis are able to survive long-term cryopreservation. Therefore, cryopreservation is a suitable method for long-term storage of E. multilocularis metacestode isolates and reduces the number of experimental animals.

Background Cysticercus tenuicollis (larvae of Taenia hydatigena) is a frequent cosmopolitan endoparasite of ruminants. The infestation by this parasite is underestimated since it is neither zoonotic nor inducing high economic losses in the sheep sector. Methods This study aimed at estimating different parasitological indicators, Cysticercus tenuicollis infestation in small ruminants using a slaughterhouse‐based survey in Northeast Tunisia. A total number of 3,692 sheep and 78 goats were examined in the slaughterhouse of Menzel Temime. Results The overall prevalence was estimated to be 2.8 (106/3692) and 8.9% (7/78) in sheep and goats, respectively. The abundance in these two species was 0.24 and 0.05 and the intensity 1.97 and 2.85, respectively. In goats, all the cysts were found in the mesentery, whilst, in sheep, the majority were in mesentery (96%) but also on the liver in 2% of the cases and in both organs (2%). There were only cysts with aqueous liquid with predominantly middle‐sized cysts (1 to 3 cm) corresponding to 63.15 and 70.34% in sheep and goats, respectively. Conclusion Since, in small ruminants, the infestation by C. tenuicollis indicators are not high, low cost control measures should be implemented to eliminate this parasite in Northeast Tunisia., The authors estimated the infestation prevalence of sheep and goats by Cysticercus tenuicollis. The overall prevalence was estimated to 2.8 (106/3692) and 8.9% (7/78) in sheep and goats, respectively. The abundance in these two species was 0.24 and 0.05 and the intensity was 1.97 and 2.85, respectively.

Hydatid disease has a great impact on public health, causing high morbidity and mortality. Main lines of treatment include surgery, which mostly requires the installation of a scolicidal agent into hydatid cysts to prevent dissemination. Alternatively, medical treatment involves the use of benzimidazole drugs; however, the results are not satisfactory, and new drug compounds are urgently needed. Fluralaner is a potent inhibitor of GABA-gated chloride channels and L-glutamate-gated chloride channels (GluCls) providing immediate and persistent flea, tick and mite control in dogs after a single oral dose. Researches previously identified different genes encoding ion channels in Echinococcus granulosus, making ion channel inhibitors a promising target for treating hydatid disease. Thus, the present study aimed to evaluate the effect of fluralaner on protoscolices and metacestode layers. Parasite materials (Protoscolices, Metacestodes layers) were exposed to different concentrations of the drug ranging from “12.5–100 ug/ml” and examined for viability after 1, 6 and 24 h. Morphological and ultrastructural alterations were recorded by both light and electron microscopies. Immunohistochemical staining confirmed caspase-3 activation as an indicator of apoptosis- induced therapy. The treated protoscolices and metacestode layers showed loss of the viability, the formation of vacuoles and lipid droplets, separation of the germinal layer, and damage in the laminated layer; apoptosis was prominent after treatment. These findings revealed that fluralaner has a potent scolicidal activity and suggested its therapeutic potential against hydatid disease. Further evaluations for animals and human use in the treatment and prevention of hydatid disease are needed.

Some neglected parasitic larvae and worms may cause rare human infections. They are mostly zoonotic species. Sparganosisis is the infection with a plerocercoid larva of an animal diphyllobothriid cestode. The valid species incriminated in causing human sparganosis are Spirometra erinaceieuropaei, Spirometra decipiens, Spirometra mansonoides, Spirometra theileri, and the aberrant Sparganum proliferum. Other species reported to infect human in the literature are probably nonspecific. Coenuriasisis the infection with a metacestode of Taenia species, mainly T. multiceps or T. serialis. Acanthocephaliasis, on the other hand, is the infection with acanthocephalan worms. Man was reported to be infected with at least nine acanthocephalan species, among them, Macracanthorhynchus hirudinaceus and Moniliformis moniliformis are the most common species. Hirudiniasisis is the human attack by leeches. They are temporary parasites because they attack victims only when they are hungry and drop off when they are engorged. Among all species of leeches, only true leeches especially jawed leeches are known to attack humans. These species are either freshwater or land dwellers. This review summarizes current knowledge of the public health significance of human affections by these parasites, and the recommended methods of prevention and control.

The cestode Taenia hydatigena uses canids, primarily dogs, as definitive hosts, while the metacestode larval stage cysticercus infects a range of intermediate hosts, including domestic animals such as goats, sheep, and pigs. Cysticercosis due to T. hydatigena has large veterinary and economic drawbacks. Like other taeniids, e.g., Echinococcus, intraspecific variation is found among the members of the genus Taenia. In Africa, few studies are available on the epidemiology and distribution of T. hydatigena, and even fewer studies are available on its genetic variation. In this study, we molecularly identified 11 cysticerci from sheep in Sudan and demonstrated the genetic variation based on the NADH dehydrogenase subunit 1 (nad1) and cytochrome c oxidase subunit 1 (cox1) mitochondrial genes. The isolates were correctly identified as T. hydatigena with more than 99% similarity to those in the GenBank database. Low diversity indices and insignificant neutrality indices were observed, with 3 and 2 haplotypes for the nad1 and cox1 genes, respectively. The results suggest the presence of unique T. hydatigena haplotypes in Sudan, as haplotypes with 100% similarity were not found in the GenBank database. With few available studies on the genetic variation of T. hydatigena in Africa, this report represents the first insights into the genetic variation of T. hydatigena in Sudan and constitutes useful data.

Summary Echinococcus granulosus is a tapeworm whose life cycle includes dogs and other canines as final hosts, while domestic and wild ungulates act as intermediate hosts for the tissue-invading larval stage (metacestode). E. granulosus has a worldwide geographical distribution. Protoscolices and rostellar hooks of E. granulosus are useful for diagnosis and rostellar hook morphometric features may be useful to discriminate E. granulosus and related species. The present study was aimed to determine a more suitable lytic solution and to obtain a clearest vision for performing morphometric studies on the rostellar hooks of E. granulosus protoscolices. Five fertile hydatid cyst samples were collected from sheep in Kirkuk slaughterhouse, Iraq, during June of 2015. According to the results of the present study, proteinase-K lytic solution is the best approach in morphometric analysis to get a clear vision of rostellar hooks and a safer usage in comparison with solutions containing lactophenol (lactophenol, lactophenol blue).

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by infection with the larvae of Echinococcus granulosus sensu lato (s.l.) cluster. It is urgent to identify novel drug targets and develop new drug candidates against CE. Glucose transporter 1 (GLUT1) is mainly responsible for the transmembrane transport of glucose to maintain its constant cellular availability and is a recent research hotspot as a drug target in various diseases. However, the role of GLUT1 in E. granulosus s.l. (EgGLUT1) was unknown. In this study, we cloned a conserved GLUT1 homology gene (named EgGLUT1-ss) from E. granulosus sensu stricto (s.s.) and found EgGLUT1-ss was crucial for glucose uptake and viability by the protoscoleces of E. granulosus s.s. WZB117, a GLUT1 inhibitor, inhibited glucose uptake by E. granulosus s.s. and the viability of the metacestode in vitro. In addition, WZB117 showed significant therapeutic activity in E. granulosus s.s.-infected mice: a 10 mg/kg dose of WZB117 significantly reduced the number and weight of parasite cysts (P < 0.05) as efficiently as the reference drug, albendazole. Our results demonstrate that EgGLUT1-ss is crucial for glucose uptake by the protoscoleces of E. granulosus s.s., and its inhibitor WZB117 has a therapeutic effect on CE.

The metacestode stage of Echinococcus granulosus can cause cystic echinococcosis (CE), which still widely occurs around the world. Since the early 1970s, benzimidazoles have been shown to inhibit the growth of cysts and used to treat CE. However, benzimidazoles are still ineffective in 20%-40% of cases. In order to explore the new agents against CE, we have investigated the therapeutic effect of the recombinant adenoviral vector expressing mouse IL-28B (rAd-mIL-28B) on protoscoleces-infected mice. In our study, we successfully established the model mice which infected with protoscoleces intraperitoneally. At 18 weeks post-infection, the mice received rAd-mIL-28B (1×107 PFU) weekly by intramuscular injection for 6 weeks. Compared with the untreated control (13.1 ± 2.2 g), there was a significant reduction in cysts wet weight in rAd-mIL-28B group (8.3 ± 3.5 g) (P, Author summary Echinococcosis is a chronic zoonotic parasitic disease, which is caused by the larval stage of Echinococcus granulosus (E. granulosus) and Echinococcus multiocularis (E. multiocularis). This disease is still widely prevalent in the world and seriously endangers human health and life, causing heavy burdens and economic losses to agriculture and animal husbandry. China is also one of the high incidence areas of the disease. At present, the preferred treatment is surgical excision of the parasitic mass, but patients with multiple cysts appear in multiple organs have to receive drug therapy. The approved chemotherapeutic drugs in clinic, such as albendazole (ABZ) and mebendazole, often do not work expectedly with a high rate of recurrence. Therefore, it is urgent to develop the new anti-echinococcal drug. IL-28B is an important member of type-III IFNs, which is equipped with the capacity of anti-viral activity and anti-tumor. In our previous study, we found that IL-28B could inhibit the proliferation of cervical cancer cells via down-regulating Treg cells in mice. This study mainly studied the therapeutic effect of rAd-mIL-28B on E. granulosus-infected mice, and the results showed that rAd-mIL-28B could relieve the parasitic burden and inhibit Treg cells meanwhile improve the Th1 and Th17 immune responses. It may contribute to another choice for the anti-echinococcal treatment.

A typical multivesiculated metacestode tissue has been found in the liver of a European brown hare (Lepus europaeus) originating from a northern area of Switzerland. In this study, the causative species was identified as Echinococcus multilocularis by appropriate histological and molecular analyses and corresponding DNA sequencing. This is the first confirmation of larval E. multilocularis from hares in central Europe. The metacestode tissue contained protoscolices, suggesting that the hare may contribute to the transmission of E. multilocularis in Switzerland.

BackgroundAlveolar echinococcosis (AE) is a chronic zoonosis caused by the larval form ofEchinococcus multilocularis(E. multilocularis). Current chemotherapy against AE has relied on albendazole and mebendazole, which only exhibit parasitostatic and not parasiticidal efficacy. Therefore, novel compounds for the treatment of this disease are needed.MethodsPhosphoglucose isomerase (PGI) assays were used for compound screening of seven neonicotinoids. The anti-parasitic effects of thiacloprid were then evaluated onE. multilocularismetacestode vesicles, germinal cells and protoscoleces in vitro. Human foreskin fibroblasts (HFF) and Reuber rat hepatoma (RH) cells were used to assess cytotoxicity. Glucose consumption inE. multilocularisprotoscoleces and germinal cells was assessed by measuring uptake of 2-deoxyglucose (2-DG). Molecular docking was used to evaluate the potential binding sites of thiacloprid to acetylcholine receptors. In vivo efficacy of thiacloprid was evaluated in mice by secondary infection withE. multilocularis. In addition, ELISA and flow cytometry were used to evaluate the effects of cytokines and T lymphocyte subsets after thiacloprid treatment. Furthermore, collagen deposition and degradation in the host lesion microenvironment were evaluated.ResultsWe found that thiacloprid is the most promising compound, with an IC50of 4.54 ± 1.10 μM and 2.89 ± 0.34 μM, respectively, against in vitro-culturedE. multilocularismetacestodes and germinal cells. Thiacloprid was less toxic for HFF and RH mammalian cell lines than for metacestodes. In addition, thiacloprid inhibited the acetylcholinesterase activity in protoscoleces, metacestodes and germinal cells. Thiacloprid inhibited glucose consumption by protoscoleces and germinal cells. Subsequently, transmission electron microscopy revealed that treatment with thiacloprid damaged the germinal layer. In vivo, metacestode weight was significantly reduced following oral administration of thiacloprid at 15 and 30 mg/kg. The level of CD4+T lymphocytes in metacestodes and spleen increased after thiacloprid treatment. Anti-echinococcosis-related cytokines (IL-2, IL-4, IL-10) were significantly increased. Furthermore, thiacloprid inhibited the expression of matrix metalloproteinases (MMPs 1, 3, 9, 13) and promoted collagen deposition in the host lesion microenvironment.ConclusionsThe results demonstrated that thiacloprid had parasiticidal activity againstE. multilocularisin vitro and in vivo, and could be used as a novel lead compound for the treatment of AE.Graphical abstract

Taenia martis is a tapeworm dwelling in the intestine of mustelids and a rare zoonotic cysticercosis pathogen in its larval stage. The metacestode is morphologically very similar to more prevalent cysticercosis parasites, such as the larvae of Taenia solium and Taenia crassiceps, and may be indistinguishable from other metacestodes on histological sections. However, the epidemiology of human T. martis infections is different, and for prognosis, prevention, and detection of natural parasite reservoirs, the species should be identified. We here report the molecular identification of a T. martis larva located in the pouch of Douglas in a female German patient who underwent surgery for endometriosis. This case represents the fifth human infection described worldwide; all previous cases were also in European women, involving the eye, brain, and the peritoneum.

Seven hundred sixty-five (765) adult wild boars were examined during the 2016/2017 hunting season for the research of parasites. Post mortem inspection was carried out at the slaughterhouse by the Official Veterinarian on the plucks (heart, tongue, lungs, diaphragm, and liver) of the killed animals presented by hunters. Of these, 0.8% (6/765) were positive for Echinococcus granulosus sensu lato (s.l.), and 2.6% (20/765) were positive for the metacestode stage of Taenia hydatigena (Cysticercus tenuicollis), while 0.5% (4/765) animals showed a mixed infection (Echinococcus granulosus s.l. and Taenia hydatigena). Sixty-three (63) cystic lesions were found. Of these 25,4% (16/63) were caused by Echinococcus granulosus s.l. and 74,6% (47/63) were caused by Cysticercus tenuicollis. The more involved organs were liver and lungs, in a less extension omentum and diaphragm. Parasitological analyses showed an overall prevalence of 3.9% for metacestodes in the hunted animals examined (Paoletti et al., 2018). Hydatids were molecularly characterized as E. granulosus sensu stricto. Trichinella spp. examination results showed no evidences of parasitic cysts. The products of hunting used for own consumption and direct sale to the final consumer or retailer, according to Regulation (EC) No 853/2004, lack of overall control by the Competent Authority. This is a critical point in the food chain of the game meat. The data obtained show the importance of the post mortem inspection and the central role of the Competent Authority to ensure not only the food safety of game meat but also to collect data for extensive epidemiological investigations on live-stocks wildlife settings having a direct impact on public health.

Esta investigación fue realizada para incrementar el conocimiento actual de los datos morfológicos y morfométricos de los ganchos rostelares de la forma larvaria (metacestode) de Echinococcus granulosus. Los protoescoÛ lices fueron aislados de hígados y pulmones de ovinos y vacunos infectados naturalmente obtenidos de los mataderos en los departamentos del Perú (Arequipa, Cuzco, Puno, Huancavelica y Junín). Se utilizó la microscopia de campo claro, la microscopia confocal, la microscopia electrónica de barrido y contraste de interferencia diferencial. La morfometría se realizó mediante el análisis de imagen computacional. La aplicación de estos ensayos indican que los ganchos grandes con frecuencia presentaban finos protectores y de superficie irregular entre el protector y el mango. Los datos también indicaron que los ganchos pequeños presentaron proctectores redondeados y robustos. La hoja no mostroÛ ningún aspecto relevante. Se observoÛ que no existe distinción morfológica clara entre los ganchos grandes y pequeños. Fue evidente diferencias fenotípicas en la forma y el tamaño de los ganchos. En conclusión, la comparación de la morfología de los ganchos rostelares grandes y pequeños mostró ciertas diferencias. Nuestro estudio demostró la utilidad de la combinación de herramientas tradicionales y nuevas para los estudios morfológicos y ayudar a resolver las cuestiones pendientes con respecto a la morfología de los ganchos rostelares.

Background Cystic echinococcosis (CE)/hydatidosis is an important neglected parasitic zoonotic disease caused by the metacestode of Echinococcus granulosus s.l. The present study was designed to identify the pulmonary CE species/genotypes in isolated human underwent to surgery in our center in Southern Iran. Methods The study population of this study were all patients in Fars province who were admitted to Namazi Hospitals for pulmonary hydatid cyst surgery. Thoracic surgery was performed in the thoracic ward and the cyst/s was removed by open surgery via posterolateral or lateral thoracotomy. DNA was extracted from the germinal layer or the protoscoleces. PCR technique was performed using the cytochrome C oxidase subunit1 (cox1) gene, and the products were sequenced. Results A total of 32 pulmonary hydatid cyst samples were collected from 9 (28%) female and 23 (72%) male aged from 4 to 74 years old. A total of 18(56%) cyst/s were in the left lobe and 14 (44%) cysts in the right lobe. Sequence analysis of the cysts showed that 24 samples (75%) were E. granulosus s.s (G1-G3) genotype and 8 (25%) were E. canadensis (G6/G7) genotype. Conclusion E.granulosus s.s genotype was the most prevalent genotype followed by E. canadensis (G6/G7) genotype. There was no significant statistical correlation between cysts’ size, location, genotype strain, and patients’ age and gender.

Cystic echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus granulosus sensu lato. The disease is characterized by the development of cystic structures inside viscera of the intermediate host, mainly liver and lungs. These cysts are formed by three layers: germinal, laminated, and adventitial layer, the latter being the local host immune response. Metacestodes that develop protoscoleces, the infective stage to the definitive host, are termed fertile, whereas cysts that do not produce protoscoleces are termed non-fertile. Sheep usually harbor fertile cysts while cattle usually harbor non-fertile cysts. Adventitial layers with fibrotic resolution are associated to fertile cysts, whereas a granulomatous reaction is associated with non-fertile cysts. The aim of this study was to analyze cellular distribution in the adventitial layer of fertile and non-fertile E. granulosus sensu stricto cysts found in liver and lungs of cattle and sheep. A total of 418 cysts were analyzed, 203 from cattle (8 fertile and 195 non-fertile) and 215 from sheep (64 fertile and 151 non-fertile). Fertile cysts from cattle showed mixed patterns of response, with fibrotic resolution and presence of granulomatous response in direct contact with the laminated layer, while sheep fertile cysts always displayed fibrotic resolution next to the laminated layer. Cattle non-fertile cysts display a granulomatous reaction in direct contact with the laminated layer, whereas sheep non-fertile cysts display a granulomatous reaction, but in direct contact with the fibrotic resolution. This shows that cattle and sheep cystic echinococcosis cysts have distinct local immune response patterns, which are associated to metacestode fertility.

Background and Aim: Some rat cestodes are zoonotic and are capable of parasitizing humans and animals, raising serious concerns regarding human and veterinary health. The study aimed to determine the prevalence and risk factors for cestodes in Egyptian house rats and to characterize the cestodes molecularly. Materials and Methods: The current survey examined 115 house rats (Rattus rattus) in two cities (Edfu and Aswan) in Egypt's Aswan Governorate for cestode infection using integrated molecular approaches (polymerase chain reaction, sequencing, and phylogenetic analysis) and morphological/morphometrical approaches. Results: The cestodes identified in this study exhibited the typical morphological characteristics of Hymenolepis diminuta (Rudolphi, 1819), Hymenolepis nana (Siebold, 1852) (from rat intestine), and Hydatigera taeniaeformis (from rat liver). The species prevalence rates from these three studies were reported to be 8.7%, 10.4%, and 20.9%, respectively. The ribosomal DNA (ITS1, 18S, and complete ITS) sequences revealed that the hymenolepid sequences were highly distinct but were related to other sequences in the GenBank database, with some sequences showing high similarities to those of H. nana and H. diminuta. In addition, the H. taeniaeformis sequences (ITS2 and mitochondrial cytochrome c oxidase subunit 1 [mtCOX1]) obtained in this study were highly similar to some Taenia taeniaeformis GenBank sequences. The constructed phylogram revealed that the hymenolepidid tapeworms examined in this study were classified into four major branches (the majority of which were hybrids of the two species) and belonged to the genus Hymenolepis. In addition, the phylogram of H. taeniaeformis assigned this species to T. taeniaeformis. Conclusion: When typical hymenolepid morphology is combined with molecular and phylogenetic divergence, it may indicate the existence of possible cryptic species. In addition, on the basis of the phylogenetic analysis, genetic diversity within T. taeniaeformis may exist as determined by comparing the metacestode mtCOX1 sequences. The current study presents the prevalence values of zoonotic cestodes and contributes to the body of knowledge, including identification keys and the use of molecular tools for species confirmation.

International audience; Assessing the genetic diversity of the parasite Echinococcus multilocularis provides key information about the temporal and spatial strain flow in a given area. Previous studies indicated that a historical endemic area conventionally presents a relatively high genetic diversity, whereas peripheral or newly endemic areas exhibit a more restricted variability of the parasite. The Swiss plateau region is part of the European historically endemic area, and the genetic diversity has already been investigated by assessing either human metacestode isolates or adult worms from foxes. To date, there have been no studies covering the whole geographical area affected by the parasite. The aim of the present study was to make use of the domestic pig to investigate the genetic diversity of E. multilocularis in relation to spatial distribution. A total of 55 E. multilocularis-induced hepatic lesions from slaughtered pigs from Switzerland were studied using EmsB microsatellite analyzes, and findings were compared to already published data (originating from human, primate, foxes, and rodent samples). A total of 12 EmsB profiles were described among the domestic pigs, some of them presenting a clear spatial organization in the Swiss plateau, with three of the main profiles geographically separated. One of the 12 EmsB profiles has been newly identified for Switzerland in this study, while the other 11 profiles had been previously described in other Swiss E. multilocularis isolates from other hosts. Overall, a total of 18 EmsB profiles have so far been described within the Swiss endemic area. Six profiles appeared only among human, primate, rodent, and fox samples. Based on a richness and diversity accumulation analysis, the sampling efficiency for the whole studied area has now been improved considerably by compilation of 178 E. multilocularis specimens obtained from four different intermediate and one definitive host species in Switzerland.

Cysticercus tenuicollisas metacestode ofTaenia hydatigenais the most prevalent taeniid species in livestock. Eighty-eightC. tenuicollissamples were collected from sheep (n= 44) and goats (n= 44) of the northern Iran from 2015 to 2016. The isolated parasites were characterized by morphometric keys. The DNA of the larval stage was extracted, amplified and sequenced targeting mitochondrial12S rRNAandCox 1markers. A significant difference in larval rostellar hook length was observed in12S rRNAhaplotypes. Analysis of molecular variance of12S rRNAindicated a moderate genetic diversity in theC. tenuicollisisolates. The pairwise sequence distance ofC. tenuicollisshowed an intra-species diversity of 0.3–0.5% and identity of 99.5–100%. Using the12S rRNAsequence data we found a moderate genetic difference (Fst; 0.05421) inC. tenucollisisolates collected from livestock of the northern and southeastern regions of Iran. We concluded that the genetic variants ofC. tenuicollisare being undoubtedly distributing mostly in different parts of Iran. Further studies with a larger number ofT. hydatigenaisolates collected from various intermediate and definitive hosts are needed to study this evolutionary assumption and also to determine the apparent genetic differences observed in the studied regions.

Echinococcus multilocularis, a heteroxen and zoonotic parasite, is found in the intestine of carnivores, particularly foxes. Adult cestodes are regarded apathogenic in definitive hosts, while metacestode, the alveolar form, is high pathogenic for intermediate hosts. The alveolar cyst causes a maling tumor-like lesions with infiltrative, proliferative and destructive character which locates in the liver primarily, then metastasizes to other organs. If it is not treated in intermediate hosts it causes irreversible symtoms and death after located in vital organs such as liver, lungs, brain. Humans are infected by oral uptake of the viable eggs, accidentally. Because its life-cycle depends on relationship between hunter and hunting, endemic areas of the parasite are limited. The cestoda is found only in the Northern Hemisphere, while some countries are regarded high-endemic, such as Turkey. However, there is a few study on epidemiology of the parasite in Turkey, except human cases. In the review, data on the distribution of E. multilocularis in definitive and intermediate hosts in the world are presented, and the situation of the parasite in Turkey has been evaluated in detail.

Coenurosis is a serious parasitic disease of herbivorous animals caused by the metacestode of Taenia multiceps (Coenurus cerebralis). Accordingly, a significant amount of research is currently dedicated to the development of appropriate antigens for use in rapid and accurate coenurosis diagnosis kits. In the present study, antigen B (AgB) and thioredoxin peroxidase (TPx) from T. multiceps were cloned and expressed using a prokaryotic system, molecular characterization of Tm-AgB was determined by bioinformatical analyses. The serological diagnostic potentials of rTm-AgB and rTm-TPx were evaluated by indirect ELISA and compared with those of previously reported rTm-AnxB2, rTm-HSP70, and rTm-GST. The results showed that Tm-AgB is a specific lipoprotein of cestodes with good thermal stability. The ELISA assay showed that rTm-AgB exhibited a sensitivity of 95.8% and a specificity of 87.5%, indicating its strong potential for serological diagnosis of T. multiceps.

Albendazole, as the main anti-echinococcal benzimidazole, has demonstrated safe and effective therapeutic outcomes in the treatment of echinococcosis. The emergence of resistance or reduced response to albendazole sulfoxide (ABZ_SOX) and other benzimidazoles have been demonstrated in several parasitic helminths of medical and veterinary importance. As the genetic makeup and miRNA profile of helminths affects their response to albendazole sulfoxide, the present study was conducted to investigate the expression of miRNAs in different developmental stages of Echinococcus granulosus exposed to albendazole sulfoxide in vitro. Different developmental stages of the helminth were obtained from in vitro cultured E. granulosus in monophasic and diphasic media. In both ABZ-SOX-treated and control parasites miRNAs were extracted from microcysts, intact protoscoleces and strobilated worms with one and three segments. Expression of two miRNAs, let-7 and miR-61 was evaluated using RT-qPCR for each stage. Results of the present study revealed significant differential expression of both let-7 and miR-61 at different drug concentrations. A significant difference of let-7 expression was observed between the strobilated and metacestode stages of E. granulosus exposed to ABZ-SOX. In the treated protoscoleces, let-7 expression was significantly reduced in the presence of ABZ-SOX at 1000 μg/ml concentration. In contrast higher expression levels were documented in the segmented worms. In the microcysts exposed to different drug concentrations a significant decline of miR-61 expression was demonstrated. Also, a significant increase in expression of miR-61 was observed in one proglottid worms as well as the protoscoleces. Under high drug concentration or long-term exposure of the protoscoleces to ABZ-SOX significantly higher miR-61 expression was observed compared to the controls. Our findings suggested that under in vitro benzimidazole exposure the expression of two E. granulosus miRNAs were significantly affected in the microcyst stage. This study presents the first evidence of the nature of benzimidazole effects on miRNA expression in platyhelminths.

Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil / University of S?o Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Pathology. S?o Paulo, SP, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. University of S?o Paulo. Faculty of Veterinary Medicine and Animal Science. Department of Pathology. S?o Paulo, SP, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. We describe a case of microscopic liver lesion caused by larval cestode in a frugivorous bat (Molossus molossus) from the Western Brazilian Amazon. Histopathological analysis of liver indicated the occurrence of metacestode associated with multifocal histiocytic response and the phylogenetic analysis of Cox-I and 18S rDNA genes indicated that the parasite belonged to the family Paruterinidae. This is the first identification of cestodes of the family Paruterinidae in bats and may suggest a broad range of paruterinid tapeworm hosts to be investigated in the Brazilian Amazon.

The essential oil (EO) of Thymus capitatus, seven fractions (F1–F7) obtained from silica gel chromatography, and several pure EO components were evaluated with respect to in vitro activities against Echinococcus multilocularis metacestodes and germinal layer (GL) cells. Attempts to evaluate physical damage in metacestodes by phosphoglucose isomerase (PGI) assay failed because EO and F1–F7 interfered with the PGI-activity measurements. A metacestode viability assay based on Alamar Blue, as well as transmission electron microscopy, demonstrated that exposure to EO, F2 and F4 impaired metacestode viability. F2 and F4 exhibited higher toxicity against metacestodes than against mammalian cells, whereas EO was as toxic to mammalian cells as to the parasite. However, none of these fractions exhibited notable activity against isolated E. multilocularis GL cells. Analysis by gas chromatography-mass spectrometry showed that carvacrol was the major component of the EO (82.4%), as well as of the fractions F3 (94.4%), F4 (98.1%) and F5 (90.7%). Other major components of EO were β-caryophyllene, limonene, thymol and eugenol. However, exposure of metacestodes to these components was ineffective. Thus, fractions F2 and F4 of T. capitatus EO contain potent anti-echinococcal compounds, but the activities of these two fractions are most likely based on synergistic effects between several major and minor constituents.

The article examines the presence of metacestodes on the liver capsule in two wild boars and on the liver capsule and mediastinum in moose. Cysticerci were identified as Taenia hydatigena metacestodes by morphological features—size and shape of rostellar hooks and molecular analysis of the partial sequences of cytochrome c oxidase subunit 1 gene. Molecular analysis revealed similarities between the metacestodes isolated from the wild mammals in the present study to T. hydatigena in European wolves. It is possible that infection of moose and wild boar with T. hydatigena metacestode is related to the growth in the wolf population in Europe. Electronic supplementary material The online version of this article (10.1007/s10393-019-01392-9) contains supplementary material, which is available to authorized users.

The metacestode stage of Echinococcus granulosus and Echinococcus multilocularis cause cystic echinococcosis and alveolar echinococcosis, respectively, which result in severe medical and veterinary problems. In this study, as an exploration of novel treatment agents against echinococcosis, we demonstrated that ampelopsin (AMP), which is extracted from Ampelopsis grossedentata and has been clinically used for treatments of various types of diseases including cancers for a long time, exhibited profound in vitro effect against E. granulosus protoscoleces and E. multilocularis metacestodes. Furthermore, in vitro cytotoxicity assay also demonstrated that AMP at the effective dose against E. granulosus protoscoleces and E. multilocularis metacestodes did not show significant toxicity to human hepatocytes. These results suggest that AMP has the potential as an alternative agent against echinococcosis.

Taenia multiceps, one of the most widely distributed zoonotic tapeworm parasites, is able to parasitize the small intestine of canids. The metacestode of T.multiceps is fatal to ruminants and causes important economic losses in livestock. However, molecular characteristics of T.multiceps and coenurus in China are still unclear. In this study, 36 goat isolates of the coenurus stage and 18 dog isolates of the adult stage of T.multiceps were obtained from three geographical areas in China and the isolated parasite above were analyzed by amplifying the partial of cytochrome coxidase subunit 1(pcox1), 12S ribosomal RNA (12S rRNA) from mitochondrial DNA (mtDNA) regions and an internal transcribed spacer (ITS) of ribosomal DNA (rDNA). These DNA sequences obtained from T.multiceps and coenurus were employed to evaluate the nucleotide diversity and confirm the relationship between T.multiceps and coenurus. Sequences variation were 0–1.4%, 0–1.5%, 0–4.2% for pcox1, 12S rRNA and ITS, respectively, among T.multiceps and coenurus isolates obtained in this study. In Sichuan province, sequence variations for Coenurus cerebralis isolated from Yaan city were 0–1.4% for pcox1, 0–1.0% for 12S rRNA and 0–2.1% for ITS. In Hunan province, variations were 0–1.0%, 0–1.5% and 0–3.3% for corresponding genes for non-coenurus cerebralis isolated from Changsha city, while variations of T.multiceps isolates from Xiangxi autonomous prefecture were 0–1.0%, 0–1.1% and 0–3.4% for pcox1, 12S rRNA and ITS, respectively. Phylogenetic analysis based on pcox1 sequences indicated that all cerebral and noncerebral metacestodes belong to T.multiceps. These results provide reference values for future molecular epidemiological and biological study on T.multiceps in dogs and intermediate hosts.

Porcine cysticercosis, caused by metacestodes of Taenia solium is an important emerging zoonotic disease with public health and economic significance. Pigs acquire the disease through consumption of Taenia solium eggs excreted by human tapeworm carriers. The present study was conducted to investigate the prevalence of porcine cysticercosis in Nagpur and Mumbai region of Maharashtra, India by P/M examination of carcasses followed by histopathology of affected organs in infected animals and molecular identification of cysts for confirmation. Out of 1000 pigs examined during slaughter, three pigs were found to be heavily affected with T. solium cysts giving a prevalence of 0.3%. Histological section of brain in infected animals revealed marked vascular congestion of meninges, mild neuronal degeneration, perivascular cuffing and gliosis while the liver showed the infiltration of mononuclear cell, predominantly eosinophils throughout the parenchyma. Some degree of calcification was observed in the cysts lodged in liver while calcification was not evident in case of cysts lodged in brain, tongue, diaphragm and skeletal muscle. Molecular identification by PCR using two sets of oligonucleotide primers against LSU rRNA gene and Mt-Cox1 gene of T. solium confirms the cysts to be that of T. solium. The molecular diagnostics methods have been considered for validation in conjunction with P/M inspections, parasitological and histopathological examinations. The study confirms the presence of porcine cysticercosis in the two regions and demands proper sanitary measures to minimize the risk of infection from zoonoses and food safety point of view.

Canids, particularly dogs, constitute the major source of cystic echinococcosis (CE) infection to humans, with the majority of cases being caused byEchinococcus granulosus(G1 genotype). Canine echinococcosis is an asymptomatic disease caused by adult tapeworms ofE. granulosussensu lato (s.l.). Information on the population structure and genetic variation of adultE. granulosusis limited. Using sequenced data of the mitochondrial cytochromecoxidase subunit 1 (cox1) we examined the genetic diversity and population structure of adult tapeworms ofE. granulosus(G1 genotype) from canid definitive hosts originating from various geographical regions and compared it to that reported for the larval metacestode stage from sheep and human hosts.Echinococcus granulosus(s.s) was identified from adult tapeworm isolates from Kenya, Libya, Tunisia, Australia, China, Kazakhstan, United Kingdom and Peru, including the first known molecular confirmation from Gaza and the Falkland Islands. Haplotype analysis showed a star-shaped network with a centrally positioned common haplotype previously described for the metacestode stage from sheep and humans, and the neutrality indices indicated population expansion. Low Fst values suggested that populations of adultE. granulosuswere not genetically differentiated. Haplotype and nucleotide diversities forE. granulosusisolates from sheep and human origin were twice as high as those reported from canid hosts. This may be related to self-fertilization ofE. granulosusand/or to the longevity of the parasite in the respective intermediate and definitive hosts. Improved nuclear single loci are required to investigate the discrepancies in genetic variation seen in this study.

Cystic echinococcosis (CE) is a zoonotic disease worldwide caused mainly by the metacestode Echinococcusgranulosus. Hydatidosis disease is common in all countries of world, especially in the Middle East, inaddition to Asia, Africa and Europe. A person becomes infected with this disease through accidentalconsumption of water, soil or food contaminated with the faeces of infected dogs, which is the most commontype of method of infection. This parasite is transmitted to dogs when it ingests the infected organs of otheranimals that contain hydatid cysts. A study was conducted to study the infection rate between women andmen in Baghdad governorate. The results showed a highly significant increase in the incidence of infectionwith hydatid cyst among females (70.00%) in comparison to males (30.00%). The oldest age of hydatidosispatients was between 31-40 years (30.00%) with a significant differences between age groups and gender,while the lowest percentage was at age 41-50, in addition 51-60 age reached (10.00%). In regard to theprofession, the highest value of infection recorded in housewives (60.00%) and the lower percentages(6.67%) in the employees’ category. However, the most infection rate was within under primary educationlevel (40.00%), while the lowest percentage was at university education level (3.33%). The incidence ofliver infection (100%) is higher than the other organs, Moreover, it is the only affected organ that contains alarge number of hydatid cysts, Compared with lung, kidneys and spleen, which each recorded only two cystfor each of these affected organs in hydatid cyst patients, which was represented by significant differencesat (P

A total of 13 metacestodes were collected from the lung and parietal pleura from a red brocket deer (Mazama americana) from the Peruvian Amazon. All metacestodes were identified as cysticerci of Taenia omissa by morphological and molecular analyzes. Cytochrome c oxidase subunit 1 sequences from the new isolate T. omissa had more than 96.8% identity with other Peruvian isolates of the species previously sequenced. Lower similarities (93.8-95.8%) were verified between Peruvian and Canadian isolates. This finding adds a new intermediate host for T. omissa and also expands its geographical distribution.

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by infection with the larvae ofEchinococcus granulosus sensu lato(s.l.) cluster. It is urgent to identify novel drug targets and develop new drug candidates against CE. Glucose transporter 1 (GLUT1) is mainly responsible for the transmembrane transport of glucose to maintain its constant cellular availability and is a recent research hotspot as a drug target in various diseases. However, presence and role of GLUT1 inE. granulosus s.l.(EgGLTU1) was unknown. In this study, we cloned a conserved GLUT1 homology gene (named EgGLUT1-ss) fromE. granulosus sensu stricto(s.s.) and found EgGLUT1-ss was crucial for glucose uptake of the protoscoleces ofE. granulosus s.s..WZB117, a GLUT1 inhibitor, inhibited glucose uptake ofE. granulosus s.s.and the viability of the metacestodein vitro.In addition, WZB117 showed potent therapeutic activity inE. granulosus s.s.-infected mice: a 10 mg/kg dose of WZB117 significantly reduced the number and weight of parasite cysts as well as the reference drug, albendazole. Our data have defined EgGLUT1 as a keyE. granulosus s.l.vulnerability target, involved in its glucose uptake from the host; this opens a new avenue to identify drugs with an ideal activity profile for the treatment of CE.

Cysticercosis is a disease caused by the metacestode of the parasite Taenia solium (T. solium). In humans, the most severe complication of the disease is neurocysticercosis. The drug of choice to treat this disease is albendazole; however, the bioavailability and efficacy of the drug are variable. Therefore, new molecules with therapeutic effects against this and other parasitic infections caused by helminths must be developed. Naphthoquinones are naphthalene-derived compounds that possess antibacterial, antifungal, antitumoral, and antiparasitic properties. The aim of this work was to evaluate the in vitro anti-helminthic effect of 2-[(3-chlorophenylamino)phenylmethyl]-3-hydroxy-1,4-naphthoquinone, isolated from a natural source and then synthesized (naphthoquinone 4a), using an experimental model of murine cysticercosis caused by Taenia crassiceps (T. crassiceps). This compound causes paralysis in the cysticerci membrane from day 3 of the in vitro treatment. Additionally, it induces changes in the shape, size, and appearance of the cysticerci and a decrease in the reproduction rate. In conclusion, naphthoquinone 4a has in vitro cysticidal activity on T. crassiceps cysticerci depending on the duration of the treatment and the concentration of the compound. Therefore, it is a promising drug candidate to be used in T. crassiceps and possibly T. solium infections.

Echinococcus is a genus of zoonotic tapeworms that involve carnivores as definitive hosts and herbivores and rodents as intermediate hosts. Echinococcus undergoes four developmental stages: adult worm, egg, metacestode, and protoscolex. Echinococcus spp. have a complex lifecycle involving two mammalian hosts. Echinococcus adult worms reside in the small intestines of definitive hosts and discharge the gravid proglottids or eggs via feces into soil, pasture land, livestock farms, and water. As patients infected with Echinococcus spp. often present with nonspecific clinical symptoms, accurate diagnosis of echinococcosis requires detailed history and physical exam, as well as input from various laboratory procedures. Molecular detection of Echinococcus species-specific genes using standard, multiplex, real-time, or real-time multiplex-nested polymerase chain reaction allows rapid, sensitive, and specific confirmation and genotyping of echinococcosis. Despite having significant structural, biological, and molecular similarities, Echinococcus spp. show differences in their host preference, pathogenicity, and clinical presentations.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Background Alveolar echinococcosis (AE) is caused by metacestode larva of the tapeworm Echinococcus multilocularis. AE diagnostics currently rely on imaging techniques supported by serology, but unequivocal detection of AE is difficult. Although polymerase chain reaction (PCR)-based methods to detect tapeworm DNA in biopsies have been suggested for several species, no validated protocol adhering to accepted guidelines has so far been presented for AE diagnostics. We herein established a PCR protocol for metacestode biopsies and technically evaluated the method using isolated parasite DNA and cells, biopsies of clinically relevant material, and formalin fixed paraffin-embedded (FFPE) human tissue blocks. We compared the results with an immunochemical (IHC) approach using the monoclonal antibody Em2G11 specific for the antigen Em2 of E. mulitlocularis. Methodology/Principal findings Based on tapeworm 12S rDNA sequences we established and validated a PCR protocol for robust detection of as little as 50 parasite cells per specimen and report 127 cases of positive identification of Echinococcus species in samples from humans and animals. For further validation, we analyzed 45 liver, heart, brain, and soft tissue samples as well as cytological probes of aspirates of FFPE-material from 18 patients with clinically confirmed AE. Of each patient we analyzed (i) fully viable lesions with laminated layer; (ii) tissue with mAbEm2G11-positive small particles of E. multilocularis (spems); (iii) mAbEm2G11-negative tissue adjacent to the main lesion; and (iv) lymph node tissue with mAbEm2G11-positive spems. To identify the areas for the PCR-based approach, we performed IHC-staining with the monoclonal antibody Em2G11. Micro-dissected tissue of these areas was then used for PCR-analysis. 9 of 15 analyzed samples with viable E. multilocularis lesions with laminated layer were positive by PCR. Of this group, all samples preserved for less than 6 years (6/6) were tested positive. 11 of 15 samples of spems and 7 of 9 samples of the control group mAbEm2G11-negative tissue were negative by PCR. We further show that all probes from lymph nodes with spems are PCR negative. Conclusions/Significance We present a sensitive PCR method for the detection of E. multilocularis in human tissue, particularly in fresh biopsy material and tissue blocks stored for less than 5 years. While the diagnostic sensitivity of material containing only spems was higher using IHC, PCR detection was possible in IHC negative liver tissue and in patients with negative serology. Our results support the view that spems do not contain parasitic DNA or viable cells of the parasite. spems thus most probably do not directly contribute to metastasis formation during AE., Author summary Alveolar echinococcosis (AE) is a potentially lethal zoonosis during which metacestode larval tissue of the tapeworm Echinococcus multilocularis grows like a malignant tumor, infiltrating the human liver. Current AE diagnosis, which mainly relies on imaging techniques (ultrasound, computed tomography, magnetic resonance tomography) supported by serology, is not always suitable to unequivocally identify an infection. In this work the authors present a PCR-based approach to detect the parasite in biopsy material taken from patients. The method was first validated for routine laboratory use employing isolated parasite DNA as well as defined numbers of parasite cells in clinically relevant settings. The method was then verified under clinically relevant settings using pathology samples from patients with defined AE. Particularly in cases when these samples had been stored for less than 6 years, the PCR methodology was highly suitable to identify the infection, even when serology was negative. The authors show that small particles of E. multilocularis (spems), containing surface material of the parasite and often located in the draining adjacent lymph nodes, are PCR negative and, thus, most probably do not contain viable parasite cells. The authors conclude that in cases of doubtful serology and imaging, a combination of immunochemical staining methods with PCR are reliable means to unequivocally detect the infection.

Hydatigera taeniaeformis formerly referred to as Taenia taeniaeformis is a cestode of cats (definitive hosts) and rodents (intermediate hosts). The prevalence of the metacestode larval stage has been reported in rodents in many parts of the world even though the genetic polymorphisms or intraspecies variation is still understudied. Here, we report a prevalence of 22.09% (38/172) from an urban rodent population in Pakistan and a nucleotide diversity (cox1) of 0.00463 among the population. Infection was higher in male (27.85%) and adult (32.29%) rats than female and sub-adult/young rats. Interestingly, The median-joining network and phylogenetic construction comprising isolates from China, Japan, Kenya, Laos, Malaysia, Senegal, the United Arab Emirates, and countries in Europe demonstrated that Pakistani H. taeniaeformis are closer to Asian and African population than those of European origin. The results of the study will add-in preliminary data for H. taeniaeformis and will also contribute to understand the global molecular epidemiology and population structure of H. taeniaeformis.

Cystic echinococcosis (CE) is a neglected tropical disease, caused by metacestode (larval) form of the Echinococcus granulosus sensu lato (sl) in humans. MicroRNAs (miRNAs) are small, stable, tissue-specific RNA molecules encoded by the genome that are not translated into proteins. Circulating miRNA expression profiles vary in health and disease. The aim of this study is to determine the altered cellular pathways in CE by comparing the miRNA profiles of controls and CE patients with active or inactive cysts. Following abdominal ultrasonography (US) examination, 20 patients diagnosed with active CE (CE1, CE2, CE3a and CE3b) or inactive CE (CE4 and CE5) and three healthy controls were included in the study. The expression profiles of 372 biologically relevant human miRNAs were investigated in serum samples from CE patients and healthy controls with miScript miRNA HC PCR Array. Compared with the control group, expression of 6 miRNAs (hsa-miR-4659a-5p, hsa-miR-4518, hsa-miR-3977, hsa-miR-4692, hsa-miR-181b-3p, hsa-miR-4491) and one miRNA (hsa-miR-4687-5p) were found to be downregulated in CE patients with active and inactive cysts, respectively (p < 0.05). For downregulated miRNAs in this study, predicted targets were found to be associated mainly with cell proliferation, apoptosis, cell-cell interactions and cell cycle regulation. Further studies in this direction may elucidate the pathogenesis of human CE and the relationship between CE and other pathologies.

Echinococcus multilocularis larvae, predominantly located in the liver, cause a tumor-like parasitic disease, alveolar echinococcosis (AE), that is characterized by increased infiltration of various immune cells, including macrophages, around the lesion that produces an “immunosuppressive” microenvironment, favoring its persistent infection. However, the role of hepatic macrophages in the host defense against E. multilocularis infection remains poorly defined. Using human liver tissues from patients with AE and a hepatic experimental mouse model of E. multilocularis, we investigated the phenotype and function of hepatic macrophages during the parasite infection. In the present study, we found that a large number of CD68+ macrophages accumulated around the metacestode lesion in the liver of human AE samples and that both S100A9+ proinflammatory (M1 phenotype) and CD163+ anti-inflammatory (M2 phenotype) macrophages were significantly higher in close liver tissue (CLT) than in distant liver tissue (DLT), whereas M2 macrophages represent the dominant macrophage population. Furthermore, E. multilocularis-infected mice exhibited a massive increase in macrophage (F4/80+) infiltration in the liver as early as day 5, and the infiltrated macrophages were mainly monocyte-derived macrophages (CD11bhi F4/80int MoMFs) that preferentially differentiated into the M1 phenotype (iNOS+) at the early stage of E. multilocularis infection and then polarized to anti-inflammatory macrophages of the M2 phenotype (CD206+) at the chronic stage of infection. We further showed that elimination of macrophages by treatment of mice with clodronate-liposomes before E. multilocularis infection impaired worm expulsion and was accompanied by a reduction in liver fibrosis, yielding a high parasite burden. These results suggest that hepatic macrophages may play a dual role in the establishment and development of E. multilocularis metacestodes in which early larvae clearance is promoted by M1 macrophages while persistent metacestode infection is favored by M2 macrophages.

Background Serotonin is a phylogenetically ancient molecule that is widely distributed in most metazoans, including flatworms. In addition to its role as a neurotransmitter, serotonin acts as a morphogen and regulates developmental processes. Although several studies have focused on the serotonergic nervous system in parasitic flatworms, little is known on the role of serotonin in flatworm development. Methods To study the effects of serotonin on proliferation and development of the cestode Echinococcus multilocularis, we cloned the genes encoding the E. multilocularis serotonin transporter (SERT) and tryptophan hydroxylase (TPH), analyzed gene expression by transcriptome analysis and whole mount in situ hybridization (WMISH) and performed cell culture experiments. Results We first characterized orthologues encoding the SERT and TPH, the rate-limiting enzyme in serotonin biosynthesis. WMISH and transcriptomic analyses indicated that the genes for both SERT and TPH are expressed in the parasite nervous system. Long-term treatment of parasite stem cell cultures with serotonin stimulated development towards the parasite metacestode stage. Mature metacestode vesicles treated with serotonin showed increased rates of incorporation of the thymidine analogue 5-ethynyl-2′-deoxyuridine (EdU), indicating stimulated cell proliferation. In contrast, treatment with the selective serotonin reuptake inhibitor paroxetine strongly affected the viability of parasite cells. Paroxetine also caused structural damage in metacestode vesicles, suggesting that serotonin transport is crucial for the integrity of parasite vesicles. Conclusions Our results indicate that serotonin plays an important role in E. multilocularis development and proliferation, providing evidence that the E. multilocularis SERT and TPH are expressed in the nervous system of the protoscolex. Our results further suggest that the E. multilocularis SERT has a secondary role outside the nervous system that is essential for parasite integrity and survival. Since serotonin stimulated E. multilocularis metacestode development and proliferation, serotonin might also contribute to the formation and growth of the parasite in the liver. Graphical Abstract