Echinococcus Granulosus Sensu Lato Research Articles

Cystic echinococcosis in Cyprus: historical retrospective and finding of two Echinococcus granulosus sensu lato species.

Cystic echinococcosis in Cyprus: historical retrospective and finding of two Echinococcus granulosus sensu lato species.

Immunohistochemistry as a Reliable Tool for the Diagnosis of Cystic Echinococcosis in Patients from Sardinia, Italy-A Confirmatory Study.

Cystic Echinococcosis (CE) is a zoonotic disease caused by the larval stage of the tapeworm Echinococcus granulosus sensu lato (s.l.). This study aims to investigate the use of two monoclonal antibodies (mAbEmG3 and mAbEm2G11) by immunohistochemistry (IHC) to confirm the diagnosis of CE in human patients, in particular in those cases in which other techniques fail to provide a correct or conclusive diagnosis. For this purpose, a survey on 13 patients was performed. These subjects were referred to Sardinian hospitals (Italy) from 2017 to 2022 and were suspected to be affected by CE. Our findings from these 13 patients showed the detection of E. granulosus sensu stricto by IHC in 12 of 13 echinococcal cysts, as one sample was of a non-parasitological origin. The results confirmed that IHC, by means of the mAbEmG3 and mAbEm2G11, is a reliable diagnostic tool that showed a very high performances when tested on strain of E. granulosus s.l. from Sardinia.

Echinococcus granulosus ubiquitin-conjugating enzymes (E2D2 and E2N) promote the formation of liver fibrosis in TGFβ1-induced LX-2 cells

BackgroundCystic echinococcosis (CE) is a widespread zoonosis caused by the infection with Echinococcus granulosus sensu lato (E. granulosus s.l.). CE cysts mainly develop in the liver of intermediate hosts, characterized by the fibrotic tissue that separates host organ from parasite. However, precise mechanism underlying the formation of fibrotic tissue in CE remains unclear.MethodsTo investigate the potential impact of ubiquitin-conjugating enzymes on liver fibrosis formation in CE, two members of ubiquitin-conjugating (UBC) enzyme of Echinococcus granulosus (EgE2D2 and EgE2N) were recombinantly expressed in Escherichia coli and analyzed for bioinformatics, immunogenicity, localization, and enzyme activity. In addition, the secretory pathway and their effects on the formation of liver fibrosis were also explored.ResultsBoth rEgE2D2 and rEgE2N possess intact UBC domains and active sites, exhibiting classical ubiquitin binding activity and strong immunoreactivity. Additionally, EgE2D2 and EgE2N were widely distributed in protoscoleces and germinal layer, with differences observed in their distribution in 25-day strobilated worms. Further, these two enzymes were secreted to the hydatid fluid and CE-infected sheep liver tissues via a non-classical secretory pathway. Notably, TGFβ1-induced LX-2 cells exposed to rEgE2D2 and rEgE2N resulted in increasing expression of fibrosis-related genes, enhancing cell proliferation, and facilitating cell migration.ConclusionsOur findings suggest that EgE2D2 and EgE2N could secrete into the liver and may interact with hepatic stellate cells, thereby promoting the formation of liver fibrosis.Graphical

Ultrasound diagnosis of cystic echinococcosis: updates and implications for clinical management.

The diagnosis of cystic echinococcosis (CE) is based on imaging. Detection of a focal lesion with morphological characteristics of Echinococcus granulosus sensu lato metacestode is the starting point for the diagnostic workup. In organs explorable with ultrasound (US), this is the method of choice for both aetiological diagnosis of CE and staging of the CE cyst. Staging in terms of lesion morphology is also needed when serology is added to the diagnostic workflow when imaging alone is inconclusive. Finally, staging guides the clinical management of uncomplicated CE, especially in the liver. This commentary provides an overview of the most up-to-date evidence backing the above-mentioned role of US in the diagnosis and clinical management of CE. Finally, we outline future perspectives for the improvement of CE diagnosis.

Untargeted metabolomics to discriminate liver and lung hydatid cysts: Importance of metabolites involved in the immune response

The Echinococcus granulosus sensu lato species complex is responsible for the neglected zoonotic disease known as cystic echinococcosis (CE). Humans and livestock are infected via fecal-oral transmission. CE remains prevalent in Western China, Central Asia, South America, Eastern Africa, and the Mediterranean. Approximately one million individuals worldwide are affected, influencing veterinary and public health, as well as social and economic matters. The infection causes slow-growing cysts, predominantly in the liver and lungs, but can also develop in other organs. The exact progression of these cysts is uncertain. This study aimed to understand the survival mechanisms of liver and lung CE cysts from cattle by determining their metabolite profiles through metabolomics and multivariate statistical analyses. Non-targeted metabolomic approaches were conducted using quadrupole-time-of-flight liquid chromatography/mass spectrometry (LC-QTOF-MS) to distinguish between liver and lung CE cysts. Data processing to extract the peaks on complex chromatograms was performed using XCMS. PCA and OPLS-DA plots obtained through multiple statistical analyses showed interactions of metabolites within and between groups. Metabolites such as glutathione, prostaglandin, folic acid, and cortisol that cause different immunological reactions have been identified both in liver and lung hydatid cysts, but in different ratios. Considering the differences in the metabolomic profiles of the liver and lung cysts determined in the present study will contribute research to enlighten the nature of the cyst and develop specific therapeutic strategies.

Evaluation of the Protoscolicidal Activity of Humulus lupulus Methanolic Extracts on Echinococcus granulosus Sensu Stricto.

The larval stage of the parasite Echinococcus granulosus sensu lato (s.l) is responsible for cystic echinococcosis (CE), a long-term infection affecting humans and animals worldwide, and constitutes a serious public health concern. If left untreated, CE can cause serious damage to multiple organs, especially the liver and lungs. Regarding the treatment, in the last few years, the use of pharmacological treatment has increased, suggesting that in the future, drug therapy may replace surgery for uncomplicated cysts. However, the only available anthelmintic drug to treat this infection is the albendazole, which has an efficacy that does not exceed 50%. On the basis of the above-mentioned evidence, new and improved alternative treatments are urgently needed. The use of natural products and their active fractions and components holds great promise as a valuable resource for the development of novel and effective therapies. Hop (Humulus lupulus L.) is a bittering agent in the brewing industry for which the sedative, digestive, anti-inflammatory, and antimicrobial effects have been reported. The purpose of this study was to assess the in vitro efficacy of methanolic extracts from the leaves of hop varieties against E. granulosus sensu stricto (s.s) protoscoleces. Varieties Mapuche and Victoria caused a stronger protoscolicidal effect compared to the Bullion, Cascade, and Traful varieties (P < 0.01), coinciding with their highest content of flavonoids, total polyphenols, and saponins. The viability of protoscoleces treated with the varieties Mapuche and Victoria decreased to approximately 50% at days 5 y 8, respectively, showing alterations such as soma contraction and impaired microtriches. After 18 days of treatment with both varieties, protoscoleces were completely altered both structurally and ultrastructurally. In conclusion, the methanolic extracts of the H. lupulus varieties Mapuche and Victoria demonstrated a marked in vitro effect against E. granulosus s.s. protoscoleces. The beer-making industry exclusively uses hop cones, leaving behind large amounts of hop leaves as an agricultural by-product that is not being utilized. On the basis of our study, we propose that hop leaves could also be used as a source of secondary metabolites with anthelmintic activity.

Effects of annexin B18 from Echinococcus granulosus sensu lato on mouse macrophages

Cystic echinococcosis (CE) is a zoonotic disease, caused by Echinococcus granulosus sensu lato (E. granulosus s. l.), which posed significant public health concern globally. E. granulosus s. l. annexin B18 (EgANXB18) acts as a secretory protein, exerting a crucial influence in mediating host-parasite interactions. Recombinant annexin B18 (rEgANXB18) was expressed by Escherichia coli and the immunoreactivity was assessed by western blotting. The binding affinity between rEgANXB18 and total protein of RAW264.7 cells was assessed by ELISA. The impact of rEgANXB18 on the metabolic activity of RAW264.7 cells was assayed by Cell Counting Kit-8 assay. The mRNA levels of polarization markers (inducible nitrous oxide synthase (iNOS) and arginase 1 (Arg1)) and key cellular factors (IL-1β，IL-6，IL-10 and TNFα) were evaluated by qRT-PCR. rEgANXB18 was successfully expressed and recognized by E. granulosus s.l. infected canine sera, as well as could bind to the total protein of RAW264.7 cells. Additionally, rEgANXB18 could promote metabolic activity at 5, 10, 20, and 40 μg/mL while no significant impact on metabolic activity was observed at 80 μg/mL. Co-culture RAW264.7 cells with rEgANXB18 resulted in significantly upregulation of the transcript levels of polarization markers iNOS and Arg1. Moreover, rEgANXB18 significantly upregulated the transcript levels of IL-1β, IL-6, TNFα, and IL-10, while dose-effect relationship was observed in IL-1β, IL-6, and IL-10. Our results indicated that EgANXB18 showed the potential to regulate immune response of macrophages by shifting the cell polarization and cytokine profile, thereby promoting the parasitism of CE.

Understanding the role of pigs in the transmission of zoonotic Echinococcus ortleppi in Haryana, India.

The etiological agents of zoonotic cystic echinococcosis comprise the Echinococcus granulosus sensu lato (s.l.) species complex. The present study was aimed at investigating the zoonotic genotypes of Echinococcus granulosus s.l. circulating in the pig population of Haryana, India. Out of 253 slaughtered pigs screened, 5 showed the presence of hydatid cysts. The amplification of the partial mitochondrial NADH dehydrogenase subunit 1 (nad1) gene for the molecular confirmation and phylogenetics of the retrieved metacestodes (n = 2) revealed the presence of E. ortleppi. The sequences generated herein exhibited 99.80% homology to the GenBank archived E. ortleppi sequences. Cladistics targeting genetic diversity and haplotype network analysis involved 37 E. granulosus s.l. GenBank archived sequences from India corresponding to different hosts (large and small ruminants and humans) along with the sequences (n = 2) generated in the present study. Overall, 14 haplotypes with high haplotype (0.780 ± 0.059) and low nucleotide (0.033 ± 0.010) diversities were recorded for the overall data set, which evinced a population expansion. The median-joining haplotype network revealed a stellate shape of E. granulosus sensu stricto (s.s.) sequences, which was indicative of rapid population expansion. High genetic differentiation (FST = 0.840 - 0.983) and low gene flow (Nm = 0.003 - 0.047) were recorded between the pig intermediate hosts infected with E. ortleppi and other hosts infected with E. granulosus s.s. The findings are of paramount significance for the formulation of effective control strategies considering the public health and economic impact of cystic echinococcosis.

Weighted gene co-expression network analysis reveals immune evasion related genes in Echinococcus granulosus sensu stricto.

Cystic echinococcosis (CE) is a zoonotic disease caused by the tapeworm Echinococcus granulosus sensu lato (s.l). In the intermediate host, this disease is characterized by the growth of cysts in viscera such as liver and lungs, inside of which the parasite develops to the next infective stage known as protoscoleces. There are records that the infected viscera affect the development and morphology of E. granulosus s.l. protoscolex in hosts such as buffalo or humans. However, the molecular mechanisms that drive these differences remains unknown. Weighted gene co-expression network analysis (WGCNA) using a set of RNAseq data obtained from E. granulosus sensu stricto (s.s.) protoscoleces found in liver and lung cysts reveals 34 modules in protoscoleces of liver origin, of which 12 have differential co-expression from protoscoleces of lung origin. Three of these twelve modules contain hub genes related to immune evasion: tegument antigen, tegumental protein, ubiquitin hydrolase isozyme L3, COP9 signalosome complex subunit 3, tetraspanin CD9 antigen, and the methyl-CpG-binding protein Mbd2. Also, two of the twelve modules contain only hypothetical proteins with unknown orthology, which means that there are a group of unknown function proteins co-expressed inside the protoscolex of liver CE cyst origin. This is the first evidence of gene expression differences in protoscoleces from CE cysts found in different viscera, with co-expression networks that are exclusive to protoscoleces from liver CE cyst samples. This should be considered in the control strategies of CE, as intermediate hosts can harbor CE cysts in liver, lungs, or both organs simultaneously.

Investigation of patients with new infection of echinococcal cyst in Sardinia, Italy

Cystic Echinococcosis (CE) is a zoonotic disease caused by the larval stage of a tapeworm of Taeniidae family, genus Echinococcus and species Echinococcus granulosus sensu lato (s.l.). CE is a worldwide public health problem and is highly incident in all Mediterranean areas.Following clinical, image techniques and serological investigations all 83 subjects involved in the study were diagnosed for CE. General and clinical data were entered into a database and evaluated. The 43.37% were female and 56.63% male, mean age was 50.71 while the range most represented (22.7%) was between 61->70 years. The purposes of our survey were to investigate these 83 patients enrolled in the study and to deeply examine 20 (24.10%) patients that developed a new echinococcal cyst. Moreover, the causes at the basis of the onset of a new cyst were analysed, together with a possible correlation with different treatments related to primary infection corresponding to surgery (n=7), albendazole (n=6), PAIR (n=3) and watch and wait (n=4). A possible link with medical treatments of the primary infection was observed in the subjects who underwent surgery or PAIR and a likely correlation attributable to high environmental contamination in subjects managed with drugs or watch and wait was detected. Moreover, our analysis evidenced that patients with a new infection presented a more severe diagnosis along with a major mortality rate. Finally, these data may have an important contribution for an epidemiological point of view concerning the percentage of CE in a specific geographical endemic area, such as Sardinia.

Inhibition of AMPK activation in Echinococcus granulosus sensu stricto limits the parasite's glucose metabolism and survival.

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by larvae of the Echinococcus granulosus sensu lato (s.l.) cluster. There is an urgent need to develop new drug targets and drug molecules to treat CE. Adenosine monophosphate (AMP)-activated protein kinase (AMPK), a serine/threonine protein kinase consisting of α, β, and γ subunits, plays a key role in the regulation of energy metabolism. However, the role of AMPK in regulating glucose metabolism in E. granulosus s.l. and its effects on parasite viability is unknown. In this study, we found that targeted knockdown of EgAMPKα or a small-molecule AMPK inhibitor inhibited the viability of E. granulosus sensu stricto (s.s.) and disrupted the ultrastructure. The results of in vivo experiments showed that the AMPK inhibitor had a significant therapeutic effect on E. granulosus s.s.-infected mice and resulted in the loss of cellular structures of the germinal layer. In addition, the inhibition of the EgAMPK/EgGLUT1 pathway limited glucose uptake and glucose metabolism functions in E. granulosus s.s.. Overall, our results suggest that EgAMPK can be a potential drug target for CE and that inhibition of EgAMPK activation is an effective strategy for the treatment of disease.

Anthelmintic Effect of Cannabidiol against Echinococcus granulosus sensu stricto.

Cystic echinococcosis is a global parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus sensu lato. Cystic echinococcosis affects more than 1 million people worldwide, causing important economic costs in terms of management and livestock associated losses. Albendazole is the main drug used in treating human cystic echinococcosis. In spite of this, its low aqueous solubility, poor absorption, and consequently erratic bioavailability are the cause of its chemotherapeutic failures. Based on the described problem, new treatment alternatives urgently need to be developed. The aim of the present research was to study the in vitro and in vivo efficacy of cannabidiol (CBD), the second most abundant component of the Cannabis sativa plant, was demonstrated against E. granulosus sensu stricto. CBD (50 µg/mL) caused a decrease in protoscoleces viability of 80 % after 24 h of treatment which was consistent with the observed tegumental alterations. Detachment of the germinal layer was observed in 50 ± 10% of cysts treated with 50 µg/mL of CBD during 24 h. In the clinical efficacy study, all treatments reduced the weight of cysts recovered from mice compared with the control group. However, this reduction was only significant with ABZ suspension and the CBD + ABZ combination. As we could observe by the SEM study, the co-administration of CBD with ABZ suspension caused greater ultrastructural alteration of the germinal layer in comparison with that provoked with the monotherapy. Further in vivo research will be conducted by changing the dose and frequency of CBD and CBD + ABZ treatments and new available CBD delivery systems will also be assayed to improve bioavailability in vivo.

Molecular discrimination of G1 and G3 genotypes of Echinococcus granulosus sensu stricto obtained from human, cattle, and sheep using the mitochondrial NADH dehydrogenase subunit 5 marker

Cystic echinococcosis (CE) is a common zoonotic disease caused by the larval form of Echinococcus granulosus sensu lato. This study determined the genotype and haplotype differences using the NADH dehydrogenase subunit 5 gene in hydatid cyst samples. Human (n = 12), cattle (n = 28), and sheep (n = 31) hydatid cyst isolates were included. Seventy-one genomic DNA samples were successfully extracted, and a 759 bp mitochondrial NADH dehydrogenase subunit 5 gene fragment was amplified by PCR. Following the sequence analysis, E. granulosus sensu stricto isolates were identified as G1 (n = 61) and G3 (n = 10). A total of 23 haplotypes were obtained from the 71 E. granulosus s.s. G1 and G3 samples. The main haplotype was Hap01 (60.56 %), which consisted of the G1 genotype. The second largest haplotype was Hap04, which consisted entirely of the G3 genotype. Hap14 acted as a bridge between the G1 and G3 genotypes. This study identifies G1 as the dominant genotype in humans and farm animals in Turkey. High haplotype and nucleotide diversity in genotypes were observed. Additionally, this is the first report on the phylogeography and gene flow models of the E. granulosus s.s. population in Turkey using the NADH dehydrogenase subunit 5 gene, the best marker distinguishing between G1 and G3 genotypes.

A Canadian children's hospital's experience with cystic echinococcosis over 30 years: A case series.

Cystic echinococcosis (CE) or hydatid disease caused by the cestode Echinococcus granulosus sensu lato is an uncommon infection in Canada especially among children. There are limited reports describing the clinical presentation and management in Canadian children. The medical records of all children diagnosed with CE at a quaternary paediatric centre in Ontario between January 1988 and August 2021 were retrospectively reviewed. The clinical course, management, and outcomes of each case were summarized. We report two paediatric cases of cystic echinococcosis (CE) in detail and review four additional cases seen at our institution over 33.5 years. The first case was a previously healthy 12-year-old boy with pulmonary CE resulting in unilateral lung collapse and mediastinal shift, who was presumedly infected while living in the Middle East. The second case was a previously healthy 3-year-old girl with pulmonary CE acquired locally in southern Ontario. Four other cases of CE with hepatic involvement (median age 12.5 years) were identified during the study period. Five out of six patients received both surgical and medical therapy. CE is a rare but serious disease seen in southern Canada that has historically been associated with travel or migration. Due to changes in urban wildlife landscapes and increased global migration, CE may become more prevalent in Canadian children. We describe the first locally acquired case in rural southern Ontario diagnosed at our centre. Prompt recognition of this infection in children by health care providers is important to prevent morbidity and mortality.

Seroprevalence and determinants of Echinococcus granulosus sensu lato infection among owned dogs in Ibadan, Nigeria.

Humans acquire cystic echinococcosis through accidental ingestion of Echinococcus granulosus (EG) eggs released into the environment by infected dogs. This study aimed to determine the presence of EG antibodies and their determinants in owned dogs in Ibadan, Nigeria. Sera from 185 dogs on routine visits to veterinary clinics were analysed by indirect ELISA. A questionnaire was administered to dog owners to obtain data on demographics, management, and environmental factors. Data were analysed using descriptive statistics, univariate analysis, and logistic regression at α0.05. The median age of the dogs was 20 months (range 2 - 96). The seroprevalence of EG infection was 33.51% (95% CI: 26.71, 40.32%). Low educational level of dog owners (OR: 2.8; 95% CI: 1.3, 5.8); local dog breeds (OR: 3.2; 95% CI: 1.7, 6.0); confinement (OR: 0.4; 95% CI: 0.2, 0.8); interaction with other dogs (OR: 3.2; 95% CI: 1.4, 7.3); self-dewormed dogs (OR: 2.6; 95% CI: 1.2, 5.9) and never dewormed dogs (OR: 4.39; CI: 1.9, 10.0) were significantly associated with EG seropositivity. Our results suggest also that local breed of dog (AOR: 2.4; 95% CI: 1.2, 4.9), self-deworming of dogs (AOR: 2.6; 95% CI: 1.1, 5.9) and the absence of any dog deworming treatment (AOR: 2.9; 95% CI: 1.2, 7.1) might be predictive of EG seropositivity. Our study provides evidence of EG infection in owned dogs, especially in those medicated by owners. Deworming practices should be based on the recommendations of a veterinarian to effectively prevent EG transmission from dogs to humans.

Echinococcus granulosus sheep strain (G1) as the predominant genotype in definitive host (dogs) isolates in northeastern Iran

Echinococcus granulosus sensu lato (E. granulosus s.l.) is a zoonotic parasite, causing cystic echinococcosis in humans. In the present study, prevalence and genotypes of E. granulosus s.l. was assessed in stools collected from 244 dogs including 138 stray and 106 domestic animals using high resolution melting curve (HRM) method. Initially, to detect taeniid eggs in feces, all samples were examined using the formalin-ether techniques. Genomic DNA was extracted from the positive samples and E. granulosus s.l. was differentiated from other Taeniidae parasites using SSU-rDNA gene and E. granulosus s.l. was analyzed for genotyping using HRM based on the cox1 gene. In total, 12.7% (31/244) of the samples were positive for Taeniidae eggs. In addition, among the positive samples, 77.4% (24/31) were positive for E. granulosus s.l.. In details, 11.3% (12/106) of the domestic dogs and 8.7% (12/138) of the stray dogs were positive for E. granulosus s.l.. The results of HRM analysis showed that all E. granulosus s.l. isolates were G1 strain. Findings of the present study indicated a considerable prevalence of E. granulosus G1 among dogs in the northeast of Iran and imply a serious risk of transmitting to humans and livestock.

Does the expression of granzyme B participate in inflammation, fibrosis, and fertility of hydatid cysts?

Echinococcus granulosus (sensu lato), a cestode that is endemic in Egypt, causes cystic echinococcosis (CE), a significant but neglected zoonotic disease that is prevalent throughout the world. Infected hydatid cysts are classified as fertile or non-fertile based on the presence of protoscoleces; nevertheless, the mechanism of non-fertile CE cysts remains unknown. The study aimed to assess whether granzyme B (GrB) expression and CD4 + /CD8 + could be related to the induction of non-fertile CE cysts. A total of fifty-eight individuals diagnosed with visceral hydatid cysts were selected, and they were further divided according to cyst fertility into fertile and non-fertile. Immunohistochemistry for CD4, CD8, and GrB was done. According to the results, hydatid cysts are common in adults and have no gender preference. The same clinical and laboratory data were shared by patients with fertile and non-fertile cysts (p = 0.186). GrB expression was not impacted by the fibrous deposition inside the hydatid cyst wall (p = 0.85); however, GrB was significantly correlated with the inflammatory density (p = 0.005). GrB expression was also found to be significantly higher in non-fertile cysts (p = 0.04). GrB expression is positively correlated with CD4 and CD8 expression. In conclusion, the expression of GrB in hydatid cysts may exacerbate the inflammatory response and impede cyst fertility while not affecting the fibrous deposition in the cyst wall.

Hepatic macrophages play critical roles in the establishment and growth of hydatid cysts in the liver during Echinococcus granulosus sensu stricto infection.

Cystic echinococcosis (CE) is a worldwide neglected zoonotic disease caused by infection with the larval stage of the tapeworm Echinococcus granulosus sensu lato (E. granulosus s.l.), which predominantly resides in the liver accompanied by mild inflammation. Macrophages constitute the main cellular component of the liver and play a central role in controlling the progression of inflammation and liver fibrosis. However, the role of hepatic macrophages in the establishment and growth of hydatid cysts in the liver during E. granulosus sensu stricto (E. granulosus s.s.) infection has not been fully elucidated. Here, we showed that CD68+ macrophages accumulated in pericystic areas of the liver and that the expression of CD163, a marker of anti-inflammatory macrophages, was more evident in active CE patients than in inactive CE patients. Moreover, in a mouse model of E. granulosus s.s. infection, the pool of hepatic macrophages expanded dramatically through the attraction of massive amounts of monocyte-derived macrophages (MoMFs) to the infection site. These infiltrating macrophages preferentially polarized toward an iNOS+ proinflammatory phenotype at the early stage and then toward a CD206+ anti-inflammatory phenotype at the late stage. Notably, the resident Kupffer cells (KCs) predominantly maintained an anti-inflammatory phenotype to favor persistent E. granulosus s.s. infection. In addition, depletion of hepatic macrophages promoted E. granulosus s.s. larval establishment and growth partially by inhibiting CD4+ T-cell recruitment and liver fibrosis. The above findings demonstrated that hepatic macrophages play a vital role in the progression of CE, contributing to a better understanding of the local inflammatory responses surrounding hydatid cysts and possibly facilitating the design of novel therapeutic approaches for CE.

Protective efficacy of six recombinant proteins as vaccine candidates against Echinococcus granulosus in dogs.

Cystic echinococcosis (CE) is caused by the infection of Echinococcus granulosus sensu lato (E. granulosus s.l.), one of the most harmful zoonotic helminths worldwide. Infected dogs are the major source of CE transmission. While praziquantel-based deworming is a main measure employed to control dog infections, its efficacy is at times compromised by the persistent high rate of dog re-infection and the copious discharge of E. granulosus eggs into the environment. Therefore, the dog vaccine is a welcome development, as it offers a substantial reduction in the biomass of E. granulosus. This study aimed to use previous insights into E. granulosus functional genes to further assess the protective efficacy of six recombinant proteins in dogs using a two-time injection vaccination strategy. We expressed and combined recombinant E. granulosus triosephosphate isomerase (rEgTIM) with annexin B3 (rEgANXB3), adenylate kinase 1 (rEgADK1) with Echinococcus protoscolex calcium binding protein 1 (rEgEPC1), and fatty acid-binding protein (rEgFABP) with paramyosin (rEgA31). Beagle dogs received two subcutaneous vaccinations mixed with Quil-A adjuvant, and subsequently orally challenged with protoscoleces two weeks after booster vaccination. All dogs were sacrificed for counting and measuring E. granulosus tapeworms at 28 days post-infection, and the level of serum IgG was detected by ELISA. Dogs vaccinated with rEgTIM&rEgANXB3, rEgADK1&rEgEPC1, and rEgFABP-EgA31 protein groups exhibited significant protectiveness, with a worm reduction rate of 71%, 57%, and 67%, respectively, compared to the control group (P < 0.05). Additionally, the vaccinated groups exhibited an inhibition of worm growth, as evidenced by a reduction in body length and width (P < 0.05). Furthermore, the level of IgG in the vaccinated dogs was significantly higher than that of the control dogs (P < 0.05). These verified candidates may be promising vaccines for the prevention of E. granulosus infection in dogs following two injections. The rEgTIM&rEgANXB3 co-administrated vaccine underscored the potential for the highest protective efficacy and superior protection stability for controlling E. granulosus infections in dogs.

What is the role of Swiss domestic cats in environmental contamination with Echinococcus multilocularis eggs?

BackgroundThe role of the domestic cat as definitive host for Echinococcus multilocularis and thus in environmental contamination with eggs has not yet been entirely resolved. This study aimed to assess the prevalence of E. multilocularis and other gastrointestinal parasites in Swiss domestic cats and to compare the diagnostic sensitivity of different methods for the detection of intestinal taeniid infection.MethodsFaecal samples from 146 cats were included in the study. Faecal samples only were available from 55 cats; for the other 91 cats, necropsy was performed in addition to faecal sample testing. All (n = 146) faecal samples were analysed by a combined sedimentation/flotation technique (44% ZnCl2) and by the sodium acetate-acetic acid-formalin (SAF) sedimentation technique; when sufficient material was available (n = 121 samples) the Baermann-Wetzel technique was also used. Additionally, all samples were analysed by two coproantigen (copro)-quantitative PCRs (qPCR): (i) a multiplex qPCR able to detect and differentiate between E. multilocularis, Echinococcus granulosus sensu lato and Taenia spp./other cestodes (CEST-qPCR) and (ii) an E. multilocularis-specific qPCR (EM-qPCR). Finally, the intestines were examined macroscopically and microscopically for parasite stages at necropsy (n = 91) and using an intestinal scraping technique (IST) (n = 64).ResultsOf the 146 cats examined, 24 (17.1%) were infected by intestinal parasites, namely Hydatigera (syn. Taenia) taeniaeformis (8.9%), Toxocara cati (6.1%), Capillaria sp. (3.4%), hookworms (3.4%), Mesocestoides litteratus (1.4%), Giardia sp. (1.4%), Cystoisospora rivolta (1.4%), Cystoisospora felis (0.7%), Toxoplasma gondii (0.7%), Hammondia hammondi (0.7%) and Strongyloides sp. (0.7%). Necropsy and the IST revealed adult H. taeniaeformis in 12 animals, of which eight faecal samples were positive by the CEST-qPCR (sensitivity = 67%) and six samples by the sedimentation/flotation technique (sensitivity = 50%). No E. multilocularis infection was detected in the sampled cats. Using Bayesian latent class analysis, the mean posterior prevalence probability was 0.0% (95% confidence interval 0–0.83%) for E. multilocularis.ConclusionsThere was no evidence of E. multilocularis infection among the 146 cats examined, suggesting that the prevalence of this parasite is low (< 1%) in the Swiss domestic cat population. Nonetheless, some of the sampled cats were infected by parasites that have rodents as intermediate hosts, demonstrating successful predation by these cats, and some were infected with zoonotic parasites. Cats therefore should not be disregarded as potential hosts for E. multilocularis and other zoonotic parasites.Graphical