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Fasciolosis is a zoonotic infection and is considered a developing deserted tropical illness threatening ruminant productivity and causing financial losses. Herein, we applied immunoinformatics and biophysics studies to develop an epitopes vaccine against Fasciola hepatica using glutathione transferase and Cathepsin L-like proteinase as possible vaccine candidates. Using the selected proteins, B- and Tcell epitopes were predicted. After epitopes prediction, the epitopes were clarified over immunoinformatics screening, and only five epitopes, EFGRWQQEKCTIDLD, RRNIWEKNVKHIQEH, FKAKYLTEMSRASDI, TDMTFEEFKAKYLTE, and YTAVEGQCR were selected for vaccine construction; selected epitopes were linked with the help of a GPGPG linker and attached with an adjuvant through another linker, EAAAK linker. Cholera toxin B subunit was used as an adjuvant. The ExPASy ProtParam tool server predicted 234 amino acids, 25.86257 kDa molecular weight, 8.54 theoretical pI, 36.86 instability index, and -0.424 grand average of hydropathicity. Molecular docking analysis predicted that the vaccine could activate the immune system against F. hepatica. We calculated negative binding energy values. A biophysics study, likely molecular docking molecular dynamic simulation, further validated the docking results. In molecular dynamic simulation analysis, the top hit docked compounds with the lowest binding energy values were subjected to MD simulation; the simulation analysis showed that the vaccine and immune cell receptors are stable and can activate the immune system. MMGBSA of -146.27 net energy (kcal/mol) was calculated for the vaccine-TLR2 complex, while vaccine-TLR4 of -148.11 net energy (kcal/mol) was estimated. Furthermore, the C-ImmSim bioinformatics tool predicted that the vaccine construct can activate the immune system against F. hepatica, eradicate the infection caused by F. hepatica, and reduce financial losses that need to be spent while protecting against infections of F. hepatica. The computational immune simulation unveils that the vaccine model can activate the immune system against F. hepatica; hence, the experimental scientist can validate the finding accomplished through computational approaches. [ABSTRACT FROM AUTHOR]

Background: Climate change is driving the occurrence of several infectious diseases. Within a One Health action to complement the ongoing preventive chemotherapy initiative against human fascioliasis in the Northern Bolivian Altiplano hyperendemic area, field surveys showed a geographical expansion of its lymnaeid snail vector. To assess whether climate change underlies this spread of the infection risk area, an in-depth analysis of the long-term evolution of climatic factors relevant for Fasciola hepatica development was imperative. Methods: We used monthly climatic data covering at least a 30-year period and applied two climatic risk indices, the water-budget-based system and the wet–day index, both of verified usefulness for forecasting fascioliasis transmission in this endemic area. To reveal the long-term trends of the climatic factors and forecast indices, we applied procedures of seasonal-trend decomposition based on locally weighed regression and trend analysis on the basis of linear models. To further demonstrate the changes detected, we depicted selected variables in the form of anomalies. Results: This study revealed a notorious climatic change affecting most of the hyperendemic area, with a strong impact on crucial aspects of the fascioliasis transmission. Trends in maximum and mean temperatures show significant increases throughout the endemic area, while trends in minimum temperatures are more variable. Precipitation annual trends are negative in most of the localities. Trends in climatic risk indices show negative trends at lower altitudes or when farther from the eastern Andean chain. However, monthly and yearly values of climatic risk indices indicate a permanent transmission feasibility in almost every location. Conclusions: Warmer temperatures have enabled lymnaeids to colonize formerly unsuitable higher altitudes, outside the endemicity area verified in the 1990s. Further, drier conditions might lead to an overexploitation of permanent water collections where lymnaeids inhabit, favoring fascioliasis transmission. Therefore, the present preventive chemotherapy by annual mass treatments is in need to widen the area of implementation. This study emphasizes the convenience for continuous monitoring of nearby zones for quick reaction and appropriate action modification. [ABSTRACT FROM AUTHOR]

The spatial organization of gene expression dictates tissue functions in multicellular parasites. Here, we present the spatial transcriptome of a parasitic flatworm, the common liver fluke Fasciola hepatica. We identify gene expression profiles and marker genes for eight distinct tissues and validate the latter by in situ hybridization. To demonstrate the power of our spatial atlas, we focus on genes with substantial medical importance, including vaccine candidates (Ly6 proteins) and drug resistance genes (glutathione S-transferases, ABC transporters). Several of these genes exhibit unique expression patterns, indicating tissue-specific biological functions. Notably, the prioritization of tegumental protein kinases identifies a PKCβ, for which small-molecule targeting causes parasite death. Our comprehensive gene expression map provides unprecedented molecular insights into the organ systems of this complex parasitic organism, serving as a valuable tool for both basic and applied research. Fasciola hepatica is a complex multicellular pathogen and the causative agent of fascioliasis, a zoonotic disease that compromises liver function. Using spatial transcriptomics, the authors uncover the tissue-specific gene expression of F. hepatica and identify genes with expression in the surface layer for drug-target discovery. [ABSTRACT FROM AUTHOR]

Introduction: Infections with Fasciola hepatica and Ostertagia ostertagi impinge upon dairy cow health and welfare and represent a major economic factor in livestock industry. Control measures largely rely on the use of anthelminthic drugs. However, reports of anthelmintic resistance necessitate sustainable approaches. Farmer characteristics such as attitude and personality are crucial for the implementation of control strategies and on-farm practices. Methods: In the present study, the HEXACO (Honesty-Humility, Emotionality, eXtraversion, Agreeableness, Conscientiousness, Openness to experience) model of personality structure, which conceptualizes human personality, was used to evaluate the relationship of farmer aspects with on-farm bulk tank milk seropositivity for F. hepatica and O. ostertagi. Moreover, information on farm structure, housing, management, and farmers' attitude was collected in a face-to-face interview. Farm-level seropositivity for F. hepatica and O. ostertagi was predicted via elastic net regression. Results: Out of 193 farms housing 8,774 cows in the German Federal State of Bavaria, 47 farms (24.4%) were seropositive for F. hepatica, 77 farms (39.9%) for O. ostertagi, and 42 farms (21.8%) for both endoparasites. The model for F. hepatica seropositivity selected the covariates pasture access, O. ostertagi seropositivity, higher farmer conscientiousness, and organic farming as relevant predictors. Seropositivity for O. ostertagi was predicted by F. hepatica seropositivity, pasture access, organic farming, and farmers being neutral regarding their satisfaction with animal health on their farm. Higher values for the HEXACO factors extraversion and emotionality were inversely associated with O. ostertagi seropositivity. Discussion: The present work emphasizes the importance of farmer traits in regard to animal health and parasite occurrence. For the effective acceptance and implementation of sustainable control strategies for livestock helminth infections, it is crucial to consider these aspects to holistically address the challenges of managing parasitic diseases. Moreover, tailored communication strategies can be developed incorporating the understanding of individual stockman characteristics and subsequently ensuring encouragement of stakeholders. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fasciola hepatica extracellular vesicles (Hp EVs) induce extracellular matrix secretion. • Hp EVs reduce proliferation of hepatic stellate cells (HSCs) • Dicrocoelium dendriticum EVs (Dd EVs) trigger a global inflammatory response in HSCs and hepatocytes. • Dd EVs have a more potent anti-proliferative effect than Fh EVs. • Fh EVs are taken up faster and in higher amounts than Dd EVs by HSCs and hepatocytes. Fasciola hepatica and Dicrocoelium dendriticum are parasitic trematodes residing in the bile ducts of mammalian hosts, causing, in some cases, impairment of liver function and hepatic fibrosis. Previous studies have shown that extracellular vesicles released by F. hepatica (Fh EVs) and D. dendriticum (Dd EVs) induce a distinct phenotype in human macrophages, but there is limited information on the effect of parasitic EVs on liver cells, which interact directly with the worms in natural infections. In this study, we isolated Fh EVs and Dd EVs by size exclusion chromatography and labeled them with a lipophilic fluorescent dye to analyze their uptake by human hepatic stellate cells (HSC) and hepatocytes, important cell types in liver pathology, using synthetic liposomes as internal labeling and uptake control. We analyzed EV uptake and the proteome profiles after the treatment with EVs for both cell types. Our results reveal that EVs establish unique and specific interactions with stellate cells and hepatocytes, suggesting a different role of EVs derived from each parasite, depending on the migration route to reach their final niche. Fh EVs have a cytostatic effect on HSCs, but induce the extracellular matrix secretion and elicit anti-inflammatory responses in hepatocytes. Dd EVs have a more potent anti-proliferative effect than Fh EVs and trigger a global inflammatory response, increasing the levels of NF-κB and other inflammatory mediators in both cell types. These interactions may have a major influence on the progression of the disease, serving to generate conditions that may favor the establishment of the helminths in the host. [ABSTRACT FROM AUTHOR]

Fascioliasis is an often-neglected zoonotic disease caused by liver fluke Fasciola hepatica and Fasciolagigantica[1]. The life cycle of this parasite starts when eggs in mammalian stool are deposited in tepid water (22-26°C) and hatch in within two weeks, miracidia appear and develop. These miracidia invade many species of freshwater snails, in which they further develop to sporocyst and redia for 4-7 weeks. They leave as free-swimming single tailed cercaria that subsequently attach to watercress, water lettuce, mint, parsley, or khat [2, 3]. They encyst within few hours and wait to be eaten by the definite host, humans [4]. The metacercariae exist in the small intestine is releasing the young parasites, which rapidly penetrate the intestinal wall and enter the peritoneal cavity. The immature flukes penetrate the capsule of Glisson after 48h and enter the liver then migrate throughout the hepatic parenchyma till they reach the biliary system where they become adults within 3 to 4 months from the initial infection and lay eggs [4]. World health organization now recognizes human Fascioliasis as a significant public health problem and a neglected tropical disease with a great impact on human development [4]. The burden of infection is unclear, and studies have shown the geographic expansion of fascioliasis in human and livestock likely related to climate change[5]. This study aims to highlight the sociodemographic characteristics of human fascioliasis in a newly emerged endemic area at north of Iraq. [ABSTRACT FROM AUTHOR]

Fasciola hepatica is a liver fluke that resides in the bile ducts of various mammals. The parasitosis leads to economic losses in animal production estimated at USD 3.2 billion annually. It is also considered a zoonosis of great significance and a problem for public health affecting 2.4 million people worldwide. Nevertheless, besides the negative aspects of infestation, the antigens released by the fluke, F. hepatica Excretory-Secretory Products (Fh-ES) contain several immunomodulatory molecules that may be beneficial during the course of type I diabetes, multiple sclerosis, ulcerative colitis, or septic shock. This phenomenon is based on the natural abilities of adult F. hepatica to suppress proinflammatory responses. To underline the molecular basis of these mechanisms and determine the role of microRNA (miRNA) in the process, lipopolysaccharide (LPS)-activated THP-1 macrophages were stimulated with Fh-ES, followed by miRNA microarray analyses. Surprisingly, no results indicating changes in the miRNA expression profile were noted (p < 0.05). We discuss potential reasons for these results, which may be due to insufficient sensitivity to detect slight changes in miRNA expression or the possibility that these changes are not regulated by miRNA. Despite the negative data, this work may contribute to the future planning of experiments by other researchers. [ABSTRACT FROM AUTHOR]

Background: The productivity of livestock production has been greatly impacted by parasitic diseases. The infection prevalence of parasites in native and imported slaughtered animals has not received much attention, despite the fact that Saudi Arabia has data on animal parasites. This study aimed to determine the infection prevalence of parasites in slaughtered animals in relation to host origin and host age. Methods: This investigation was conducted at Al Makhwah area in southwestern Saudi Arabia for six months from September 2021 to February 2022. The examined animals were 1208 in total, including goats (504), sheep (440) and cattle (264). All the animals examined were slaughtered at official abattoirs. The collected parasites were preserved, processed and identified. Result: Out of 1208 examined, 72 were infected (5.96%). The parasite community consisted of six species, Dicrocoelium dendriticum, Fasciola hepatica, F. giagantica, Monezia expansa, Echinococcus granulosus (Hydatiid cyst) and Haemonchus contortus. Hydatidosis was a more prevalent parasitic disease. The infection prevalence of hydatidosis in the examined animals was high in cattle (4.85%) while were 3.76 and 4.77% in goats and sheep respectively. Significant differences in prevalence per host age in goats, sheep and cattle were found. The prevalence of parasites in imported animals was higher (16.67, 17.5 and 11.36% in cattle, sheep and goats respectively) as compared to that in native ones (5.42, 6.5 and 3.69% in cattle, sheep and goats respectively). Based on our findings, Hydatidosis was identified as the most prevalent parasitic disease. Imported animals had a higher parasitic infection compared to local animals. It is essential to take necessary measures to prevent the transmission of Hydatidosis and improper organ condemnation from abattoirs. We recommend conducting further research to identify the reasons why imported animals are more likely to become infected than local animals. [ABSTRACT FROM AUTHOR]

We investigated herein the prevalence of Fasciola hepatica infection in sheep at Sejnane slaughterhouse, governorate of Bizerte, Northwest of Tunisia, using three different diagnostic techniques (liver dissection, bile examination, and coprology). Faeces, liver, gall bladder as well as blood samples were collected from 603 slaughtered sheep in two seasons: winter and summer. Faecal egg counts of F. hepatica were estimated using sedimentation technique. Livers were examined for the presence of flukes, and bile collected from gall bladder was examined by sedimentation technique for the presence of F. hepatica eggs. Faecal egg counts of gastrointestinal helminths were estimated using flotation followed by the McMaster technique. Blood samples were used to estimate blood cell count (RBC) (×106/mL), haemoglobin (Hb) (g/dL), and haematocrit (Ht) (%) levels. A total of 1714 F. hepatica flukes were collected from 68 infected livers, the number of flukes per sheep ranged between naught and 195. Bile examination (16.78% ± 1.83; 51/310) showed the higher infection prevalence, followed by liver dissection (11.28% ± 1.17; 68/603) and coprology (9.12% ± 1.08; 55/603) (p = 0.015). Infection prevalences were significantly higher in young sheep aged of less than 1 year (8.13% ± 1.22; 49/498), in cross‐bred sheep (10.61% ± 1.39%; 64/478), and in summer (7.13% ± 1.82; 43/293) (p < 0.05). There was no significant difference in infection prevalence by gastrointestinal helminths in F. hepatica‐infected and F. hepatica‐non‐infected animals (p > 0.05). The overall prevalence of F. hepatica‐infected anaemic sheep was higher (22.73% ± 4.47; 20/88) than F. hepatica‐non‐infected anaemic sheep (p < 0.05). Fasciola hepatica infection is frequent in sheep from Sejnane representing hence an important constraint for the development of the sheep industry in this region. Therefore, it is necessary to establish and implement a specific control programme to reduce fasciolosis infection risks including animal owners' education. [ABSTRACT FROM AUTHOR]

Fasciola hepatica, also known as the common liver fluke, is a globally distributed trematode parasite responsible for high economic losses in ruminants. Infection with F. hepatica occurs in Polish cattle and sheep; however, very little is known about its occurrence in goats. Therefore, a serological and coproscopic survey was carried out in Polish goats to determine the herd-level prevalence of F. hepatica infection in the goat population of Poland. Between 2014 and 2022, 33 randomly selected goat herds were serologically screened in the regions of Poland for which risk of F. hepatica infection was estimated as increased based on the spatial distribution model developed within the frame of the GLOWORM project. Virtually all adult goats (>1 year-old) were tested using a commercial MM3-SERO ELISA. Risk factors for seropositive herd status were analysed in contingency tables. Also, faecal samples from 214 goat herds monitored for gastrointestinal nematode infections and anthelmintic resistance were examined using a sedimentation method. At least one seropositive goat was detected in 11 of 33 herds, indicating herd-level seroprevalence of 33.3% (95% confidence interval (CI 95%): 19.7%–50.4%). At the animal level, only 17 of 1,464 tested goats were seropositive (1.2%, CI 95%: 0.7%–1.9%). The within-herd seroprevalence ranged from 0.8% to 11.1%. The serological status of the herd was not significantly associated with the characteristics of the herd or the extent of contact with sheep. In one herd, located in central Poland, a single positive faecal sample was found indicating a herd-level prevalence of F. hepatica infection of 0.5% (CI 95%: 0.1%–2.6%). The animal's post-mortem examination revealed liver lesions typical of chronic fasciolosis. F. hepatica infection occurs sporadically in Polish goat population and its prevalence is much lower than in cattle or sheep. Therefore, treatment or prevention of fasciolosis should only be considered if it has been reliably confirmed by an accurate diagnostic test. This applies also to goats inhabiting geographical areas where F. hepatica infection appears to be widespread in cattle and sheep, very likely due to the fact that goats avoid wet areas. [ABSTRACT FROM AUTHOR]

Abstract Background Climate change is driving the occurrence of several infectious diseases. Within a One Health action to complement the ongoing preventive chemotherapy initiative against human fascioliasis in the Northern Bolivian Altiplano hyperendemic area, field surveys showed a geographical expansion of its lymnaeid snail vector. To assess whether climate change underlies this spread of the infection risk area, an in-depth analysis of the long-term evolution of climatic factors relevant for Fasciola hepatica development was imperative. Methods We used monthly climatic data covering at least a 30-year period and applied two climatic risk indices, the water-budget-based system and the wet–day index, both of verified usefulness for forecasting fascioliasis transmission in this endemic area. To reveal the long-term trends of the climatic factors and forecast indices, we applied procedures of seasonal-trend decomposition based on locally weighed regression and trend analysis on the basis of linear models. To further demonstrate the changes detected, we depicted selected variables in the form of anomalies. Results This study revealed a notorious climatic change affecting most of the hyperendemic area, with a strong impact on crucial aspects of the fascioliasis transmission. Trends in maximum and mean temperatures show significant increases throughout the endemic area, while trends in minimum temperatures are more variable. Precipitation annual trends are negative in most of the localities. Trends in climatic risk indices show negative trends at lower altitudes or when farther from the eastern Andean chain. However, monthly and yearly values of climatic risk indices indicate a permanent transmission feasibility in almost every location. Conclusions Warmer temperatures have enabled lymnaeids to colonize formerly unsuitable higher altitudes, outside the endemicity area verified in the 1990s. Further, drier conditions might lead to an overexploitation of permanent water collections where lymnaeids inhabit, favoring fascioliasis transmission. Therefore, the present preventive chemotherapy by annual mass treatments is in need to widen the area of implementation. This study emphasizes the convenience for continuous monitoring of nearby zones for quick reaction and appropriate action modification. Graphical Abstract

Fasciolosis is a neglected/re-emerging zoonotic disease caused by the trematode Fasciola hepatica that infects both livestock and humans worldwide, causing severe economic losses and public health problems. The study determined the seroprevalence of F. hepatica infection in buffaloes and its associations with age, sex, and climatic/environmental factors (derived from satellite data) to identify potential risk factors from two tropical climate subtypes in two Mexican states. A total of 725 serum samples were analyzed for the presence of anti-F. hepatica immunoglobulin G (IgG) antibodies using an indirect enzyme-linked immunosorbent assay (ELISA), with excretory-secretory (E/S) products as the antigen. The overall prevalence of the parasite in buffaloes between September 2022 and December 2022 was 10.62% (77 out of 725). The highest rate of F. hepatica infection was detected in Veracruz state (9.18%). In addition, the highest prevalence among the climate regions was found in the tropical rainforest (13.62%). In the two states studied, the highest positivity rate for fasciolosis was observed in young animals aged three years and below (21.52%) and in male buffaloes (20.00%). Using multivariate logistic regression analysis, we determined four factors (age, normalized difference vegetation index, land surface temperature day (LST day), and rainfall) to be significantly associated with an increased risk of parasitic infection. Rainfall was the variable most strongly associated with F. hepatica infection (OR 3.434; 95% CI: 2.181-5.406), followed by LST day (OR 2.832; 95% CI: 1.916-4.186). The results indicate that different factors are significantly associated with the prevalence of liver flukes and highlight the importance of continuous monitoring programs for parasite infections to prevent economic losses in buffalo production.

Abstract Background Infections with (tricho-)strongyles, Dictyocaulus viviparus or Fasciola hepatica have been shown to reduce milk production in dairy cows. However, the current published studies focused on one single helminth infection by neglecting helminth co-infections and their possible (additive) effects on host performance. Hence, for the first time, we investigated differences in the impact of patent helminth co-infections versus mono-infections on milk production parameters in individual cows. Methods A total of 1583 dairy cows from 27 herds were included in this study. Faecal samples were examined in 2015 and 2021/2022 to determine the number of eggs/larvae per gram faeces for (tricho-)strongyles, D. viviparus, F. hepatica and rumen flukes. The cows were classified as non-infected, mono-infected and co-infected. Linear mixed models were applied to analyse the association between infection status (non-infected vs. mono-infected vs. co-infected) with milk yield, milk protein and milk fat content by including potential confounders. Results Infections with (tricho-)strongyles, D. viviparus, F. hepatica and rumen flukes were detected in 100%, 28.6%, 50.0% and 21.4% of herds, and 27.4%, 2.6%, 10.8% and 0.8% of faecal samples in 2015, while 100%, 0.0%, 86.7% and 60.0% of herds and 52.3%, 0.0%, 13.3% and 26.8% of faecal samples were positive in 2021/2022. Co-infections with two or more helminth taxa were detected in 74.4% of herds and 5.0% of faecal samples in 2015, and in 93.3% of herds and 21.7% of faecal samples in 2021/2022. The correlations between strongyle EPG, D. viviparus LPG and F. hepatica EPG were significantly positive in 2015. Significantly higher mean EPGs were identified in 2015 in faecal samples presenting co-infections with F. hepatica and one or two other helminth taxa than in faecal samples presenting F. hepatica mono-infections (P = 0.013). Although expected, the infection status (mono- or co-infected) had no significant impact on milk yield, milk protein and milk fat content in the linear mixed model analyses based on individual faecal examinations. Conclusions Patent helminth co-infections had no additive detrimental impact on milk production parameters in the present study. This might be a result of presumably low worm burdens, but should be confirmed in future studies. Graphical Abstract

Fasciola hepatica is a parasitic liver trematode that causes fasciolosis in humans and dairy animals. Traditional detection of infection is based on a microscopic examination with low sensitivity. There-fore, this study was carried out to develop an accurate and rapid method to detect F. hepatica in Al-borz province. In this cross-sectional study, 386 samples were collected from livers of cattle and sheep in three slaughterhouses of Alborz. DNA was extracted, and nested-PCR was carried out based on the F. hepatica ITS-2 sequence. DNA amplification showed first and second PCR products with expected size of 336 and 208 bp respectively, as unique for F. hepatica. The results showed no cross-reaction with the negative control. Thirty-five liver samples were positive for this parasitic infection. Totally, the prevalence of F. hepatica in the slaughterhouses of Alborz, Iran was 9.07%. This is the first study of the molecular detection of F. hepatica using nested-PCR in Alborz. It is a sensitive and rapid method that will help evaluate the prevalence rate of F. hepatica infection.

Parasitic worms (helminths) establish chronic infection within mammalian hosts by strategically regulating their host’s immune responses. Deciphering the mechanisms by which host non-coding RNAs (ncRNA) co-ordinate the activation and regulation of immune cells is essential to understanding host immunity and immune-related pathology. It is also important to comprehend how pathogens secrete specific ncRNAs to manipulate gene expression of host immune cells and influence their response to infection. To investigate the contribution of both host and helminth derived ncRNAs to the activation and/or regulation of innate immune responses during a parasite infection, we examined ncRNA expression in the peritoneal macrophages from mice infected with Fasciola hepatica. We discovered the presence of several parasitic-derived miRNAs within host macrophages at 6 hrs and 18 hrs post infection. Target prediction analysis showed that these Fasciola miRNAs regulate host genes associated with the activation of host pro-inflammatory macrophages. Concomitantly, there was a distinct shift in host ncRNA expression, which was significant at 5 days post-infection. Prediction analysis suggested that these host ncRNAs target a different cohort of host genes compared to the parasite miRNAs, although the functional outcome was predicted to be similar i.e. reduced pro-inflammatory response and the promotion of a reparative/tolerant phenotype. Taken together, these observations uncover the interplay between host and parasitic ncRNAs and reveal a complementary regulation of the immune response that allows the parasite to evade immune detection and promote tissue repair for the host. These findings will provide a new understanding of the molecular interaction between parasites and host.

As animals age, they exhibit a suite of phenotypic changes, often including reductions in movement and social behaviour ('behavioural ageing'). By altering an individual's exposure to parasites, behavioural ageing may influence infection status trajectories over the lifespan. However, these processes could be confounded by age-related changes in other phenotypic traits, or by selective disappearance of certain individuals owing to parasite-induced mortality. Here, we uncover contrasting age-related patterns of infection across three helminth parasites in wild adult female red deer (Cervus elaphus). Counts of strongyle nematodes (order: Strongylida) increased with age, while counts of liver fluke (Fasciola hepatica) and tissue worm (Elaphostrongylus cervi) decreased, and lungworm (Dictyocaulus) counts did not change. These relationships could not be explained by socio-spatial behaviours, spatial structuring, or selective disappearance, suggesting behavioural ageing is unlikely to be responsible for driving age trends. Instead, social connectedness and strongyle infection were positively correlated, such that direct age–infection trends were directly contrasted with the effects implied by previously documented behavioural ageing. This suggests that behavioural ageing may reduce parasite exposure, potentially countering other age-related changes. These findings demonstrate that different parasites can show contrasting age trajectories depending on diverse intrinsic and extrinsic factors, and that behaviour's role in these processes is likely to be complex and multidirectional. This article is part of the discussion meeting issue 'Understanding age and society using natural populations'. [ABSTRACT FROM AUTHOR]

Fasciola hepatica is a parasitic liver trematode that causes fasciolosis in humans and dairy animals. Traditional detection of infection is based on a microscopic examination with low sensitivity. Therefore, this study was carried out to develop an accurate and rapid method to detect F. hepatica in Alborz province. In this cross-sectional study, 386 samples were collected from livers of cattle and sheep in three slaughterhouses of Alborz. DNA was extracted, and nested-PCR was carried out based on the F. hepatica ITS-2 sequence. DNA amplification showed first and second PCR products with expected size of 336 and 208 bp respectively, as unique for F. hepatica. The results showed no cross-reaction with the negative control. Thirty-five liver samples were positive for this parasitic infection. Totally, the prevalence of F. hepatica in the slaughterhouses of Alborz, Iran was 9.07%. This is the first study of the molecular detection of F. hepatica using nested-PCR in Alborz. It is a sensitive and rapid method that will help evaluate the prevalence rate of F. hepatica infection. [ABSTRACT FROM AUTHOR]

Abstract Background Lymnaeid snails of the genus Austropeplea are an important vector of the liver fluke (Fasciola hepatica), contributing to livestock production losses in Australia and New Zealand. However, the species status within Austropeplea is ambiguous due to heavy reliance on morphological analysis and a relative lack of genetic data. This study aimed to characterise the mitochondrial genome of A. cf. brazieri, an intermediate host of liver fluke in eastern Victoria. Methods The mitochondrial genome was assembled and annotated from a combination of second- and third-generation sequencing data. For comparative purposes, we performed phylogenetic analyses of the concatenated nucleotide sequences of the mitochondrial protein-coding genes, cytochrome c oxidase subunit 1 and 16S genes. Results The assembled mt genome was 13,757 base pairs and comprised 37 genes, including 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The mt genome length, gene order and nucleotide compositions were similar to related species of lymnaeids. Phylogenetic analyses of the mt nucleotide sequences placed A. cf. brazieri within the same clade as Orientogalba ollula with strong statistical supports. Phylogenies of the cox1 and 16S mt sequences were constructed due to the wide availability of these sequences representing the lymnaeid taxa. As expected in both these phylogenies, A. cf. brazieri clustered with other Austropeplea sequences, but the nodal supports were low. Conclusions The representative mt genome of A. cf. brazieri should provide a useful resource for future molecular, epidemiology and parasitological studies of this socio-economically important lymnaeid species. Graphical abstract

Enolase is a 47 kDa enzyme that functions within the glycolysis and gluconeogenesis pathways involved in the reversible conversion of D-2-phosphoglycerate (2PGA) to phosphoenolpyruvate (PEP). However, in the context of host-pathogen interactions, enolase from different species of parasites, fungi and bacteria have been shown to contribute to adhesion processes by binding to proteins of the host extracellular matrix (ECM), such as fibronectin (FN) or laminin (LM). In addition, enolase is a plasminogen (PLG)-binding protein and induces its activation to plasmin, the main protease of the host fibrinolytic system. These secondary 'moonlighting' functions of enolase are suggested to facilitate pathogen migration through host tissues. This study aims to uncover the moonlighting role of enolase from the parasite Fasciola hepatica, shedding light on its relevance to host-parasite interactions in fasciolosis, a global zoonotic disease of increasing concern. A purified recombinant form of F. hepatica enolase (rFhENO), functioning as an active homodimeric glycolytic enzyme of ~94 kDa, was successfully obtained, fulfilling its canonical role. Immunoblotting studies on adult worm extracts showed that the enzyme is present in the tegument and the excretory/secretory products of the parasite, which supports its key role at the host-parasite interface. Confocal immunolocalisation studies of the protein in newly excysted juveniles and adult worms also localised its expression within the parasite tegument. Finally, we showed by ELISA that rFhENO can act as a parasitic adhesin by binding host LM, but not FN. rFhENO also binds PLG and enhances its conversion to plasmin in the presence of the tissue-type and urokinase-type PLG activators (t-PA and u-PA). This moonlighting adhesion-like function of the glycolytic protein enolase could contribute to the mechanisms by which F. hepatica efficiently invades and migrates within its host and encourages further research efforts that are designed to impediment this function by vaccination or drug design. Author summary: Fasciola hepatica is a parasitic worm causing fasciolosis, primarily affecting herbivorous mammals and posing a significant veterinary problem. Furthermore, it is a zoonosis, meaning it can be transmitted to humans. F. hepatica enters the definitive host through ingestion of contaminated aquatic plants, migrating through the intestine to settle in the liver bile ducts, where it matures into the adult stage. To migrate, it utilizes various invasion strategies, including the use of multifunctional proteins, known as 'moonlighting'. In this study, we produced and molecularly characterized the parasitic enzyme enolase as a moonlighting protein to understand F. hepatica invasion mechanisms. We produced recombinant enolase with glycolytic activity, its canonical function in parasite energy production. Additionally, we localised this enzyme in the parasite's tegument, in direct contact with the host, and studied its ability to elicit an immune response early in ovine infection. Finally, we demonstrated the ability of enolase to interact with the extracellular matrix and the host's fibrinolysis, a proteolytic system responsible for dissolving blood clots. These secondary functions of F. hepatica enolase, described here for the first time, along with its localisation, suggest this protein as an interesting antigen for fasciolosis control. [ABSTRACT FROM AUTHOR]

Background: Transposable elements (TEs) are major components of eukaryotic genomes. The extensive body of evidence suggests that although they were once considered "genomic parasites", transposons and their transcripts perform specific functions, such as regulation of early embryo development. Understanding the role of TEs in such parasites as trematodes is becoming critically important. Fasciola hepatica, a parasite affecting humans and livestock, undergoes a complex life cycle in diverse environments and hosts, and knowledge about its life cycle regulation is scarce so far. Methods: We summarized the data regarding the repetitive elements in F. hepatica and conducted bulk RNA-seq analysis across its life cycle stages. TE expression profiles were analyzed, focusing on differential expression and potential homology with previously described long non-coding RNAs (lncRNAs). Results: Differential expression analysis revealed stage-specific TE transcription patterns, notably peaking during egg and metacercariae stages. Some TEs showed homology with known lncRNAs and contained putative transcription factor binding sites. Interestingly, TE transcription levels were highest in eggs and metacercariae compared to adults, suggesting regulatory roles in trematode life cycle transitions. Conclusions: These findings suggest that TEs may play roles in regulating trematode life cycle transitions. Moreover, TE homology with lncRNAs underscores their significance in gene regulation. [ABSTRACT FROM AUTHOR]

In this review article, we aim to provide an overview of fasciolosis in ruminants. Diagnosis through new coprological methods (such as Flukefinder®, FLOTAC®, and Mini-FLOTAC®) remains the most suitable approach for farms. Regarding treatment, there is a scarcity of available drugs, and resistance to them has prompted new approaches (including drug combinations, enhanced metabolism, or the use of natural compounds) to address this issue. Additionally, several researchers have developed vaccines to control the disease, but their efficacy varies, and none are currently sufficient for commercial use. Further studies are needed to better understand all aspects discussed in this manuscript, with the goal of improving diagnosis, treatment, and disease control. It is important to note that this manuscript does not delve into in-depth knowledge of the discussed aspects; rather, it provides an overview of the different methodologies related to these three aspects of parasitic disease. [ABSTRACT FROM AUTHOR]

Background: Biological invasions pose risks to the normal functioning of ecosystems by altering the structure and composition of several communities. Molluscs stand out as an extensively studied group given their long history of introduction by either natural or anthropogenic dispersal events. An alien population of the lymnaeid species Orientogalba viridis was first sighted in 2009 in southern Spain. In its native range (Australasian), this species is one of the main intermediate hosts of Fasciola hepatica, a major worldwide trematode parasite largely affecting humans, domestic animals and wildlife. Methods: We collected field populations of O. viridis from its native (Malaysia) and invaded (Spain) ranges. We performed detailed morphoanatomical drawings of the species and screened for natural infection of parasites. Individuals were molecularly characterized using ITS2 for comparison with existing sequences in a fine phylogeography study. We founded experimental populations at two different conditions (tropical, 26 °C and temperate, 21 °C) to study the life-history traits of exposed and non-exposed individuals to different F. hepatica isolates. Results: We found a 9% natural prevalence of trematode infection (98% similarity with a sequence of Hypoderaeum conoideum [Echinostomatidae]) in the Spanish field population. The haplotypes of O. viridis found in our study from Spain clustered with Australian haplotypes. Experimental infection with F. hepatica was successful in both experimental conditions but higher in tropical (87% prevalence) than in temperate (73%). Overall lifespan, however, was higher in temperate conditions (mean 32.5 ± 7.4 weeks versus 23.3 ± 6.5) and survivorship remained above 70% during the first 20 weeks. In parasite-exposed populations, life expectancy dropped from an overall 37.75 weeks to 11.35 weeks but still doubled the time for initial cercariae shedding. Cercariae shedding started at day 23 post-exposure and peaked between days 53 and 67 with an average of 106 metacercariae per snail. Conclusions: Whether O. viridis will succeed in Europe is unknown, but the odds are for a scenario in which a major snail host of F. hepatica occupy all available habitats of potential transmission foci, ravelling the epidemiology of fasciolosis. This research provides a comprehensive understanding of O. viridis biology, interactions with parasites and potential implications for disease transmission dynamics, offering valuable insights for further research and surveillance. [ABSTRACT FROM AUTHOR]

In this paper, a mathematical model for the transmission dynamics of Fasciola hepatica in cattle and snail populations is formulated and analyzed. The snail mortality rate (μs) is the most important factor that indirectly impacts the basic reproduction number (R0). A 50% change, either an increase or decrease, in the snail mortality rate will result in an approximate 50% change in the opposite direction in the value of R0. The model shows a forward bifurcation at R0 = 1, indicating that the disease dynamics undergo a critical transition at this threshold. This change signifies a transition from a disease‐free state to a persistent infection, highlighting the possibility of a continuous disease presence given specific epidemiological conditions. Simulations show that reducing miracidia, metacercariae, and snail populations, improving treatment, and lowering pathogen transfer between cattle and snails significantly decrease disease prevalence in cattle. To control the disease, transmission rates for cattle and snails must be reduced below γc = 1.4338 × 10−7 and γs = 1.1473 × 10−8, respectively. Current treatments are insufficient, and a combination of improved treatments reduced transmission rates, and increased snail mortality is recommended for better disease control. [ABSTRACT FROM AUTHOR]

Background: Lymnaeid snails of the genus Austropeplea are an important vector of the liver fluke (Fasciola hepatica), contributing to livestock production losses in Australia and New Zealand. However, the species status within Austropeplea is ambiguous due to heavy reliance on morphological analysis and a relative lack of genetic data. This study aimed to characterise the mitochondrial genome of A. cf. brazieri, an intermediate host of liver fluke in eastern Victoria. Methods: The mitochondrial genome was assembled and annotated from a combination of second- and third-generation sequencing data. For comparative purposes, we performed phylogenetic analyses of the concatenated nucleotide sequences of the mitochondrial protein-coding genes, cytochrome c oxidase subunit 1 and 16S genes. Results: The assembled mt genome was 13,757 base pairs and comprised 37 genes, including 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The mt genome length, gene order and nucleotide compositions were similar to related species of lymnaeids. Phylogenetic analyses of the mt nucleotide sequences placed A. cf. brazieri within the same clade as Orientogalba ollula with strong statistical supports. Phylogenies of the cox1 and 16S mt sequences were constructed due to the wide availability of these sequences representing the lymnaeid taxa. As expected in both these phylogenies, A. cf. brazieri clustered with other Austropeplea sequences, but the nodal supports were low. Conclusions: The representative mt genome of A. cf. brazieri should provide a useful resource for future molecular, epidemiology and parasitological studies of this socio-economically important lymnaeid species. [ABSTRACT FROM AUTHOR]

Background: Fasciola hepatica affects cattle and buffaloes causing decreased production and liver condemnation at slaughter. Objective: To determine liver condemnation frequency, temporal distribution, and associated factors, as well as the spatial distribution and economic impact of F. hepatica infection based on postmortem inspection of cattle and buffaloes processed between 2010 and 2019 at one of the main slaughterhouses in Colombia. Methods: An observational, descriptive, and cross-sectional study was carried out, with a convenience non-probability sampling. Temporal distribution of liver condemnation frequency was analyzed. Pearson χ² test was used to determine association between the dependent variable (i.e., presence/absence of adult parasites of F. hepatica) and frequency rates between months and years. Monthly rainfall data was compared with the accumulated monthly frequency. Association between the dependent variable and production type (i.e., industrial-type bovine cattle--intended for milk production, and commercial-type bovine cattle--intended for meat production), weight, and sex (odds ratios, OR and confidence intervals, 95% CI) was explored. Descriptive maps of the municipalities presenting at least one positive case of F. hepatica in 2019 and weighted prevalences, both for bovines and buffaloes, were designed. Only losses due to liver condemnation between 2010 and 2019 were considered in the economic impact analysis. Results: A total of 1,947,233 animals were processed during the study period, resulting in 3.1% overall frequency of fasciolosis. Industrial-type cattle presented 7.4% higher risk of developing F. hepatica compared to commercialtype cattle (OR=0.074; 95% CI:0.07-0.08). Likewise, male cattle presented 3.88 times more risk compared to females (OR=3.88; 95% CI:3.49-4.33). Economic losses due to liver condemnation were estimated at US$1,129,660 for the study period. Conclusion: This is the first report of Fasciola hepatica in buffaloes in Colombia. Liver condemnations in Colombia occur throughout the year, although its frequency increases during the rainy season. The economic losses, estimated by liver condemnation due to fasciolosis, are high; however, it is necessary to explore such losses considering other productive indicators and larger animal populations. This work demonstrates the importance of systematizing the information generated in slaughterhouses. [ABSTRACT FROM AUTHOR]

Fasciolosis, a globally re-emerging zoonotic disease, is mostly caused by the parasitic infection with Fasciola hepatica, often known as the liver fluke. This disease has a considerable impact on livestock productivity. This study aimed to evaluate the fluke burdens and faecal egg counts in goats that were administered phage clones of cathepsin L mimotopes and then infected with F. hepatica metacercariae. Additionally, the impact of vaccination on the histology of the reproductive system, specifically related to egg generation in adult parasites, was examined. A total of twenty-four goats, which were raised in sheds, were divided into four groups consisting of six animals each. These groups were randomly assigned. The goats were then subjected to two rounds of vaccination. Each vaccination involved the administration of 1 × 1013 phage particles containing specific mimotopes for cathepsin L2 (group 1: PPIRNGK), cathepsin L1 (group 2: DPWWLKQ), and cathepsin L1 (group 3: SGTFLFS). The immunisations were carried out on weeks 0 and 4, and the Quil A adjuvant was used in combination with the mimotopes. The control group was administered phosphate-buffered saline (PBS) (group 4). At week 6, all groups were orally infected with 200 metacercariae of F. hepatica. At week 22 following the initial immunisation, the subjects were euthanised, and adult F. hepatica specimens were retrieved from the bile ducts and liver tissue, and subsequently quantified. The specimens underwent whole-mount histology for the examination of the reproductive system, including the testis, ovary, vitellaria, Mehlis' gland, and uterus. The mean fluke burdens following the challenge were seen to decrease by 50.4%, 62.2%, and 75.3% (p < 0.05) in goats that received vaccinations containing cathepsin L2 PPIRNGK, cathepsin L1 DPWWLKQ, and cathepsin L1 SGTFLFS, respectively. Animals that received vaccination exhibited a significant reduction in the production of parasite eggs. The levels of IgG1 and IgG2 isotypes in vaccinated goats were significantly higher than in the control group, indicating that protection is associated with the induction of a mixed Th1/Th2 immune response. The administration of cathepsin L to goats exhibits a modest level of efficacy in inducing histological impairment in the reproductive organs of liver flukes, resulting in a reduction in egg output. [ABSTRACT FROM AUTHOR]

Although the negative impact of liver fluke (Fasciola hepatica) infection on production and health in cattle is generally accepted, results of individual research have been variable, ranging from important negative impacts on the animal to minimal or no impact. To add information on the impact of F. hepatica infection in growing cattle, weight gain and liver weight of young experimentally infected animals from seven controlled efficacy studies were analyzed. In each study, fluke naïve animals were inoculated with approximately 450 to 500 F. hepatica encysted metacercariae, blocked on body weight and randomly assigned into one untreated group (controls) and groups which were administered an experimental flukicide when the flukes were 4 weeks old (migrating) and sacrificed 8 weeks thereafter (12 weeks after inoculation). Data of groups which demonstrated >90% reduction of fluke counts following treatment and groups left untreated (total 103 and 47 animals, respectively) were compared. There was a significant (p < 0.0001) negative association between fluke count and weight gain while fluke count and liver weight and fluke count and relative liver weight were positively associated (p < 0.0001). Over the 8-week post-treatment period, flukicide-treated cattle had almost 15% more weight gain than the controls (50.9 kg vs. 44.4 kg; p = 0.0003). Absolute and relative liver weight was significantly (p < 0.0001) lower in flukicide-treated compared to untreated cattle. Overall, this analysis provided evidence of a substantial negative effect of early (migrating) liver fluke infection on the growth of young cattle, likely due to pathology of the liver and associated reduction in its function as the central organ for bioenergy and protein metabolism. [ABSTRACT FROM AUTHOR]

Fasciolosis caused by Fasciola hepatica is a major public health and economic problem worldwide. Due to the lack of a successful vaccine and emerging resistance to the drug triclabendazole, alternative phytotherapeutic approaches are being investigated. This study investigated the in vitro anthelmintic activity of Lavender (Lavandula angustifolia) and carob (Ceratonia siliqua L.) essential oils (EOs) against F. hepatica. The in vitro study was based on an egg hatch assay (EHA), adult motility inhibition assays, DNA damage, reactive oxygen species (ROS) level along with several oxidative stress biomarkers including glutathione peroxidase (GSH), and glutathione-S-transferase (GST), superoxide dismutase (SOD) and malondialdehyde (MDA). To this end, different concentrations of L. angustifolia and C. siliqua EOs (1, 5, 10, 25 and 50 mg/mL) were used to assess anthelmintic effects on different life stages including egg, and adults of F. hepatica for 24 hrs. The results indicated that these EOs play a significant role as anthelminthics, and the effect was dependent on time and concentration. The in vitro treatment of F. hepatica worms with both L. angustifolia and C. siliqua EOs increased DNA damage, ROS production and induction of oxidative stress (decreased SOD, GST and GSH, and increased MDA), significantly compared to control. Therefore, it can be concluded that L. angustifolia and C. siliqua EOs have the potential to be used as novel agents for the control and treatment of F. hepatica infections. Further studies are required to investigate their pharmacological potential and effectiveness in vivo for the treatment of parasitic infections. Author summary: Fasciolosis is a disease caused by a leaf-shaped trematode called Fasciola hepatica. This disease is becoming increasingly common in humans and has been reported on five continents. F. hepatica primarily infects the bile ducts of cattle, sheep and goats, causing significant economic losses to the global livestock industry. Unfortunately, this disease has been neglected and there is currently no commercially viable vaccine to prevent it. The main treatment for this disease is chemotherapy, with triclabendazole (TCBZ) being the drug of choice for controlling these parasites. However, there is growing concern about the increase in reports of drug resistance to TCBZ in parasites. Therefore, there is an urgent need to find alternative treatment methods. Natural herbal products give great hope as they contain a large reservoir of medicinal ingredients that are effectively used against various parasitic diseases. The aim of the current study is to evaluate the in vitro effect of essential oils of lavender (Lavandula angustifolia) and carob (Ceratonia siliqua L.) on F. hepatica. According to the findings of this study, L. angustifolia and C. siliqua essential oils (EOs) have significant effects as anthelmintics. The use of L. angustifolia and C. siliqua EOs in vitro significantly increased DNA damage, ROS production, and oxidative stress in F. hepatica worms. Therefore, it can be concluded that these EOs have the potential to be used as novel agents for the control and treatment of F. hepatica. [ABSTRACT FROM AUTHOR]

Simple Summary: Fasciolosis is a parasitic disease of livestock causing important economic losses worldwide, and it is also a zoonosis. The treatment is based on the use of anthelmintic drugs, but the increase in resistance and the risk of drug residues in food make this approach no longer sustainable. Developing protective vaccines for the control of fasciolosis is postulated as an appropriate treatment, but a better knowledge of the host–parasite interaction is needed. The aim of the present study was to evaluate the hepatic lesions in sheep infected and reinfected with Fasciola hepatica during the acute and chronic stages of infection and the characterization of the hepatic inflammatory infiltrates using immunohistochemistry with CD3, Foxp3, iNOS, and CD163 antibodies. The most remarkable histopathological finding was the presence of large necrotic foci and/or hemorrhages adjacent to enlarged bile ducts containing adult parasites, suggesting flukes may have caused these lesions while feeding. In the literature, necrotic foci/hemorrhages are considered a consequence of parasite migration. In both the primoinfected and reinfected groups, and during acute and chronic stages of the infection, an increase in Foxp3 T cells with respect to uninfected controls and a poor expression of iNOS was found accompanied by a strong expression of CD163, suggesting a marked M2 activation of macrophages in the hepatic lesions. Fasciolosis is an important economic disease of livestock. There is a global interest in the development of protective vaccines since the current anthelmintic therapy is no longer sustainable. A better knowledge of the host–parasite interaction is needed to design effective vaccines. To date, few studies have evaluated host–parasite interaction by comparing infected and reinfected animals. The present study evaluates the microscopical hepatic lesions in sheep infected and reinfected with Fasciola hepatica during the acute and chronic stages of infection. The histopathological study revealed the presence of necrotizing foci (NF1) associated with larvae migration during the early stages of infection in the primoinfected (PI) and reinfected (RI) groups. In the late stages of infection of the PI group and at the early and late stages of infection in the RI groups, extensive necrotizing/hemorrhagic foci (NF2) were found in the vicinity of enlarged bile ducts, some containing adult flukes, suggesting parasites may have caused NF2 while feeding. The immunohistochemical study revealed an increase in Foxp3+ T cells in both PI and RI groups with respect to the UC group and in the infiltrates adjacent to NF1 in the RI groups with respect to the PI group, suggesting the F. hepatica induce Foxp3 T cell expansion to facilitate parasite survival. In addition, in both the PI and RI groups, and during acute and chronic stages of the infection, a poor expression of iNOS was found accompanied by a strong expression of CD163, suggesting a marked M2 activation of macrophages in the hepatic lesions, which may be related with healing processes, and it also may facilitate parasite survival. The main differences between PI and RI animals were the more severe infiltration of eosinophils and Foxp3+ T cells, whereas RI did not modify M2 activation of macrophages which occurs since the early stages of primoinfection. [ABSTRACT FROM AUTHOR]

Background and Aim: The potential of plants as anthelmintics is very large, but there is still very little research conducted in the search for effective, safe, easily obtained, and affordable anthelmintic candidates. Palem putri (Veitchia merrillii) is an ornamental plant that is interesting to study because it is included in the areca nut group which is reported to have strong abilities as anthelmintics. The study aims to evaluate the anthelmintic efficacy of Veitchia merrillii against trematode worms such as Paramphistomum spp. and Fasciola hepatica. Materials and Methods: This research employs both in vitro and computational techniques. An anthelmintic in vitro test was carried out on Paramphistomum spp. worms at concentrations of 10%, 25%, and 40% (gr/v), assessing mortality index as the observable outcome, followed by a histopathological investigation of the deceased worms for tissue and cellular damage evaluation. Seventeen compounds from V. merrillii seeds were studied in silico for their anthelmintic activity against F. hepatica worms using the quantitative structure-activity relationship technique, molecular docking, and Lipinski's rule analysis for orally administered medication. Results: About 25% and 40% extracts of V. merrillii damaged the tegument organs in the worms. Seventeen compounds in V. merrillii seed extract, on average, yielded a higher anthelmintic index on F. hepatica than praziquantel. Eleven of the 17 compounds exhibit stronger affinity than praziquantel, with routine and gallic acid being the top two ligands (Î"Gbinding values: -11.65 kcal/mol and -11.07 kcal/mol, respectively). According to Lipinski's rule analysis, only routine compounds cannot be orally administered. Conclusion: The seeds of V. merrilli have potential as an anthelmintic agent for Paramphistomum spp. at concentrations of 25%-40% (gr/v). [ABSTRACT FROM AUTHOR]

Background: The potential molluscicidal extracts, obtained from indigenous plants Cannabis sativa, Acacia nilotica, and Tinospora cordifolia, were tested for toxicity against freshwater pulmonate snail Lymnaea acuminata, an intermediate host of Fasciola hepatica. The organic extracts had a significant effect on young snails. Materials and Methods: All organic extracts and column-purified fractions gave median lethal concentrations (19–100.05 mg/L; 24 h) that fell well within the threshold level of 100 mg/L, set for a potential molluscicide by the World Health Organization. Results: The toxicity of T. cordifolia stem acetone extract (96 h LC50: 16.08 mg/L) was more pronounced compared with C. sativa leaf ethanol extract (96 h LC50: 16.32 mg/L) and A. nilotica leaf ethanol extract (96 h LC50: 24.78 mg/L). β-caryophyllene, gallic acid, and berberine were characterized and identified as active molluscicidal components. Co-migration of β-caryophyllene (retardation factor [Rf] 0.95), gallic acid (Rf 0.30), and berberine (Rf 0.23) with column-purified parts of Cannabis sativa, Acacia nilotica, and Tinospora cordifolia on thin-layer chromatography demonstrates same Rf value, that is, 0.95, 0.30, and 0.23, respectively. Conclusion: This study indicates that these extracts thus represent potential plant-derived molluscicides that are worthy of further investigations. [ABSTRACT FROM AUTHOR]

The camel has played a role in human civilization since its inception and holds significant importance in the customs and agricultural practices of various nations. This study examined the prevalence of internal parasitic infestations in camels within the Al-Diwaniyah and Al-Najaf provinces of Iraq from December 2021 to September 2022. A total of 200 fecal samples were randomly collected from farm camels, revealing that these animals were affected by one or more types of intestinal parasites. Nematodes exhibited the highest prevalence at 56 %, followed by Protozoa at 28.5 %, Cestodes at 14.5 %, and Trematodes at 1 %. Among these parasites, Trichostrongylus spp. had the highest percentage at 33 %, followed by Moneizia benedeni (12.5 %), Fasciola hepatica (10.5 %), Strongyloides spp. (8 %), Giardia spp. (7 %), Nematodirus spp. (6 %), and Eimeria spp. (6 %). Furthermore, mixed-species or single-species infections in camels were observed, including Anoplcephala perfoliata (4 %), Haemonchus spp. (3.5 %), Dictyocaulus spp. (3 %), Trichuris trichura (2.5 %), Entamoeba spp. (2 %), and Balantidium coli (1 %). Additionally, nested PCR was employed to identify Trichostrongylus spp., with 45.4 % of camels testing positive for this particular parasite. [ABSTRACT FROM AUTHOR]

Anthelmintic resistance in small ruminants is a serious worldwide problem. To reduce their spread, it is essential to know the prevalence of helminths on farms and the control practices adopted. As these studies in the Calabria region of southern Italy are fragmentary and outdated, a study on the prevalence of helminths in small ruminant holdings in this area has been conducted. The measures implemented to control helminths were also evaluated through questionnaires administered to farmers. In particular, on 90 farms (45 sheep and 45 goats), 1800 faecal samples from 900 sheep and 900 goats were collected in the spring. Using the FLOTAC dual technique, parasitological examinations demonstrated the presence of gastrointestinal nematodes in 100% of sheep and goat farms, followed by Nematodirus spp. (84.44% sheep and 48.89% goats), Moniezia spp. (73.33% sheep and 35.56% goats), Trichuris ovis (48.89% sheep and 42.22% goats), lungworms (28.89% sheep and 42.22% goats), Strongyloides papillosus (40% sheep and 26.67% goats), Dicrocoelium dendriticum (13.33% sheep and 26.67% goats), Calicophoron daubneyi (6.67% sheep and 31.11% goats), Fasciola hepatica (6.67% sheep and 4.44% goats), and Skrjabinema ovis (4.44% sheep and goats). The questionnaires showed that 82% and 85% of the farmers had applied pasture rotation, and that 93.3% and 86.6% had used anthelmintics in the previous year for sheep and goats, respectively. Only 24.4% of sheep farmers and 11.3% of goat farmers had carried out parasitological tests prior to treatments. The most used classes of anthelmintics were macrocyclic lactones and benzimidazoles, and only in 21.6% and 15.6%, for sheep and goats, respectively, was drug rotation carried out. These results denote that helminths represent a health problem for small ruminants and highlight a lack of knowledge of parasite control strategies among farmers. In these conditions, anthelmintic resistance phenomena could develop over time. Therefore, it is necessary to implement all possible strategies for the control of helminths, and to prevent the spread of anthelmintic resistance phenomena on farms in southern Italy. [ABSTRACT FROM AUTHOR]

Fasciola hepatica has a complex lifecycle with multiple intermediate and definitive hosts and influenced by environmental factors. The disease causes significant morbidity in children and its prevalent worldwide. There is lack of data about distribution and burden of the disease in endemic regions, owing to poor efficacy of the different diagnostic methods used. A novel PCR-based test was developed by using a portable mini-PCR® platform to detect Fasciola sp. DNA and interpret the results via a fluorescence viewer and smartphone image analyzer application. Human stool, snail tissue, and water samples were used to extract DNA. Primers targeting the ITS-1 of the 18S rDNA gene of Fasciola sp. were used. The limit of detection of the mini-PCR test was 1 fg/μL for DNA samples diluted in water, 10 fg/μL for Fasciola/snail DNA scramble, and 100 fg/μL for Fasciola/stool DNA scramble. The product detection by agarose gel, direct visualization, and image analyses showed the same sensitivity. The Fh mini-PCR had a sensitivity and specificity equivalent to real-time PCR using the same specimens. Testing was also done on infected human stool and snail tissue successfully. These experiments demonstrated that Fh mini-PCR is as sensitive and specific as real time PCR but without the use of expensive equipment and laboratory facilities. Further testing of multiple specimens with natural infection will provide evidence for feasibility of deployment to resource constrained laboratories. [ABSTRACT FROM AUTHOR]

This study aimed to demonstrate the existence of a possible correlation between the level of liver fluke infection in cattle caused by Fasciola hepatica and the titers of anti-parasite antibodies in the blood. 113 blood samples were taken from non-dewormed pasture cattle in the communal slaughterhouse of the Jijel city in order to determine the serological titration of anti-fluke antibodies by the ELISA method. After slaughtering the animals studied, a count of parasites present in the inspected livers was carried out in order to assess the level of parasitic infection. The prevalence of bovine fasciolosis (due to Fasciola hepatica) based on counting the number of flukes in the inspected livers was around 61.06%, while the seroprevalence obtained is 55.75%. The sensitivity and specificity of the ELISA test used in this study were, respectively, 91.3% and 100%. A very strong correlation (r = 0.93 to p < 0.0001) was statistically demonstrated between the antibody titers and the number of flukes in the inspected livers. According to the results of this study, there is a strong statistical correlation between serum antibody titers and the number of flukes present in the liver (the higher the number of parasites in the liver, the higher the level of anti-flukes antibodies in the blood). [ABSTRACT FROM AUTHOR]

ABSTRACT Parasite transmission occurs in complex environments comprising multiple matrices. Trematode parasites of ruminant livestock such as the liver fluke, Fasciola hepatica and the rumen fluke, Calicophoron daubneyi, show affinity with freshwater environments shared with their amphibious snail intermediate host, Galba truncatula. Isolation of environmental DNA (eDNA) from these parasites and their snail hosts in water draining from grazing land provides opportunities for improved molecular diagnostic detection and can help identify infection risks at farm level. The detection and quantification of eDNA from other environmental matrices has received less attention but would improve the understanding of parasite dynamics on pasture. Our study has considerably extended eDNA sampling methods for the detection of parasitic trematodes of ruminant livestock and their snail intermediate host by including for the first time the analysis of soil and herbage environmental samples alongside water collections. A droplet digital PCR (ddPCR) workflow was developed to detect parasite and snail eDNA from soil, herbage, and water collected from livestock farms. For the first time, C. daubneyi eDNA was isolated from agricultural soil alongside water samples and G. truncatula eDNA was detected in water, soil, and herbage samples. No environmental samples were positive for F. hepatica eDNA. Assessing multiple environmental matrices increased the number of positive sites. Future implementation of eDNA detection methods alongside traditional parasite diagnostics can underpin more holistic evaluations of the environmental components of parasite epidemiology and facilitate adaptation to changing disease patterns.

Fasciolosis is a zoonotic infection and is considered a developing deserted tropical illness threatening ruminant productivity and causing financial losses. Herein, we applied immunoinformatics and biophysics studies to develop an epitopes vaccine against Fasciola hepatica using glutathione transferase and Cathepsin L-like proteinase as possible vaccine candidates. Using the selected proteins, B- and T-cell epitopes were predicted. After epitopes prediction, the epitopes were clarified over immunoinformatics screening, and only five epitopes, EFGRWQQEKCTIDLD, RRNIWEKNVKHIQEH, FKAKYLTEMSRASDI, TDMTFEEFKAKYLTE, and YTAVEGQCR were selected for vaccine construction; selected epitopes were linked with the help of a GPGPG linker and attached with an adjuvant through another linker, EAAAK linker. Cholera toxin B subunit was used as an adjuvant. The ExPASy ProtParam tool server predicted 234 amino acids, 25.86257 kDa molecular weight, 8.54 theoretical pI, 36.86 instability index, and −0.424 grand average of hydropathicity. Molecular docking analysis predicted that the vaccine could activate the immune system against F. hepatica. We calculated negative binding energy values. A biophysics study, likely molecular docking molecular dynamic simulation, further validated the docking results. In molecular dynamic simulation analysis, the top hit docked compounds with the lowest binding energy values were subjected to MD simulation; the simulation analysis showed that the vaccine and immune cell receptors are stable and can activate the immune system. MMGBSA of −146.27 net energy (kcal/mol) was calculated for the vaccine–TLR2 complex, while vaccine–TLR4 of −148.11 net energy (kcal/mol) was estimated. Furthermore, the C-ImmSim bioinformatics tool predicted that the vaccine construct can activate the immune system against F. hepatica, eradicate the infection caused by F. hepatica, and reduce financial losses that need to be spent while protecting against infections of F. hepatica. The computational immune simulation unveils that the vaccine model can activate the immune system against F. hepatica; hence, the experimental scientist can validate the finding accomplished through computational approaches.

Abstract The objective of this work was to compare the performances of logistic regression and machine learning algorithms to predict infection caused by Fasciola hepatica in cattle. A dataset on 30,151 bovines from Uruguay was used. Logistic regression (LR) and the algorithms k-nearest neighbor (KNN), classification and regression trees (CART), and random forest (RF) were compared. The interquartile range (IQR) and z-score were used to improve the classification and compared to each another. Sex, age, carcass conformation score, fat score, productive purpose, and carcass weight were used as independent variables for all algorithms. Infection by F. hepática was used as a binary dependent variable. The accuracies of LR, KNN, CART, and RF were 0.61, 0.57, 0.57, and 0.58, respectively. The variable importance of LR showed that adult cattle tended to be infected by F. hepatica. All models showed low accuracy, but LR successfully distinguished variables related to F. hepatica. Both the IQR and z-score show similar results in improving the classification metrics for the used dataset. In the dataset, data related to climate or factors such as body weight can improve the reliability of the model in future studies.

During a survey for helminths in reindeer (Rangifer tarandus) across the Palearctic region, eggs were found in zoo reindeer feces. These were identified as eggs of Fasciola hepatica based on their morphology, morphometrics, location, and analysis of their partial sequence of ITS rDNA region. Some of the eggs had an appendage, previously unreported. Additionally, adults of F. hepatica were studied. Eggs derived from their uteri were also appendaged. Diagnostic morphological traits of F. hepatica eggs (abopercular appendage, knob, egg shell thickening, and egg shape) are discussed in this article. Three dimensional models of F. hepatica eggs were created to demonstrate the eggs features as best as possible. Since fecal examination remains gold standard in diagnosing fasciolosis in humans and animals worldwide, our findings may contribute to improved diagnostics. This research has also shown that reindeer can be a final host for F. hepatica. We also discuss whether the Novaya Zemlya archipelago might be the northernmost site of fasciolosis.

This article discusses a rare case of Capillaria hepatica infection in a 2-year-old boy who presented with fever, rash, hepatomegaly, and peripheral eosinophilia. The diagnosis was confirmed through fine needle aspiration cytology (FNAC) of a hepatic lesion, which revealed parasitic eggs. The article provides detailed descriptions of the cytomorphological features of the infection and includes educational multiple-choice questions related to the topic. The authors emphasize the importance of FNAC in identifying rare parasitic infections and enabling timely diagnosis and management. [Extracted from the article]

Abstract Gene expression for Th1/Th2 cytokines (IL-4 and IFN-ɣ), regulatory cytokines (TGF-β and IL-10) and the transcriptional factor FoxP3 was analyzed in the liver and hepatic lymph nodes (HLN) from sheep immunized with partially protective and non-protective vaccine candidates and challenged with Fasciola hepatica. FoxP3 T cells were also evaluated by immunohistochemistry (IHQ). The most remarkable difference between the partially protected vaccinated (V1) group and the non-protected vaccinated (V2) group was a more severe expansion of FoxP3 T cells recorded by IHQ in both the liver and HLN of the V2 group as compared to the V1 group, whereas no differences were found between the V2 group and the infected control (IC) group. Similar results were recorded for FoxP3 gene expression although significant differences among V1 and V2 groups were only significant in the HLN, while FoxP3 gene expression was very similar in the V2 and IC groups both in the liver and HLN. No significant differences for the remaining cytokines were recorded between the V1 and V2 groups, but in the liver the V2 group shows significant increases of IFN-ɣ and IL-10 as compared to the uninfected control (UC) group whereas the V1 group did not. The lower expansion of FoxP3 T cells and lower increase of IFN-ɣ and IL-10 in the partially protected vaccinated group may be related with lower hepatic lesions and fluke burdens recorded in this group as compared to the other two infected groups. The most relevant change in regulatory cytokine gene expression was the significant increase of TGF-β in the liver of IC, V1 and V2 groups as compared to the UC group, which could be related to hepatic lesions.

Abstract Background Control of the zoonotic food-borne parasite Fasciola hepatica remains a major challenge in humans and livestock. It is estimated that annual economic losses due to fasciolosis can reach US$3.2 billion in agriculture and livestock. Moreover, the wide distribution of drug-resistant parasite populations and the absence of a vaccine threaten sustainable control, reinforcing the need for novel flukicides. Methods The present work analyses the flukicidal activity of a total of 70 benzimidazole derivatives on different stages of F. hepatica. With the aim to select the most potent ones, and screenings were first performed on eggs at decreasing concentrations ranging from 50 to 5 µM and then on adult worms at 10 µM. Only the most effective compounds were also evaluated using a resistant isolate of the parasite. Results After the first screenings at 50 and 10 µM, four hit compounds (BZD31, BZD46, BZD56, and BZD59) were selected and progressed to the next assays. At 5 µM, all hit compounds showed ovicidal activities higher than 71% on the susceptible isolate, but only BZD31 remained considerably active (53%) when they were tested on an albendazol-resistant isolate, even with values superior to the reference drug, albendazole sulfoxide. On the other hand, BZD59 displayed a high motility inhibition when tested on adult worms from an albendazole-resistant isolate after 72 h of incubation. Conclusions BZD31 and BZD59 compounds could be promising candidates for the development of fasciolicidal compounds or as starting point for the new synthesis of structure-related compounds. Graphical Abstract

Abstract Objectives Fasciolosis is of significant economic and public health importance worldwide. The lack of a successful vaccine and emerging resistance in flukes to the drug of choice, triclabendazole, has initiated the search for alternative approaches. In recent years, metallic nanoparticles have been extensively investigated for their anthelmintic effects. This study investigates the in vitro anthelmintic activity of copper oxide and zinc oxide nanoparticles against Fasciola hepatica. Methods The in vitro study was based on egg hatchability test (EHA), adult motility inhibition tests, DNA damage, ROS levels, as well as several biomarkers of oxidative stress, including glutathione peroxidase (GSH) and glutathione S-transferase (GST), superoxide dismutase (SOD) and malondialdehyde (MDA). For this purpose, different concentrations of copper oxide nanoparticles (CuO-NPs) and Zinc oxide nanoparticles (ZnO-NPs) (1, 4, 8, 12, and 16 ppm) were used to evaluate the anthelmintic effect on different life stages, including egg and adults of Fasciola hepatica, over 24 h. Results In vitro treatment of F. hepatica worms with both CuO-NPs and ZnO-NPs could significantly increase ROS production and oxidative stress induction (decreased SOD, GST and GSH and increased MDA) compared to control group. Conclusions Based on the results, it seems that CuO-NPs and ZnO-NPs may be effective in the control and treatment of F. hepatica infection. Further research is needed to investigate their potential for in vivo use in the treatment of parasitic infections.

Background: Snails of the Lymnaeidae family are the intermediate hosts of Fasciola species, the causative agents of fascioliasis. The purpose of this study was to determine the prevalence of Fasciola species in lymnaeid snails and to investigate the association of geoclimatic factors and Fasciola species distribution in northwestern provinces of Iran using geographical information system (GIS) data. Methods: A total of 2000 lymnaeid snails were collected from 33 permanent and seasonal habitats in northwestern Iran during the period from June to November 2021. After identification by standard morphological keys, they were subjected to shedding and crushing methods. Different stages of Fasciola obtained from these snails were subjected to the ITS1 polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method for species identification. The associations of weather temperature, rainfall, humidity, evaporation, air pressure, wind speed, elevation, and land cover with the distribution of Fasciola species were investigated. Geographical and statistical analysis was performed using ArcMap and SPSS software, respectively, to determine factors related to Fasciola species distribution. Results: Of the 2000 snails collected, 19 were infected with Fasciola hepatica (0.09%), six with F. gigantica (0.03%), and 13 with other trematodes. Among geoclimatic and environmental factors, mean humidity, maximum humidity, and wind speed were significantly higher in areas where F. hepatica was more common than F. gigantica. The altitude of F. hepatica-prevalent areas was generally lower than F. gigantica areas. No significant relationship was observed between other investigated geoclimatic factors and the distribution of infected snails. Conclusions: The present study showed the relationship of humidity and wind speed with the distribution of snails infected with F. hepatica or F. gigantica in the northwestern regions of Iran. In contrast to F. gigantica, F. hepatica was more prevalent in low-altitude areas. Further research is recommended to elucidate the relationship between geoclimatic factors and the presence of intermediate hosts of the two Fasciola species. [ABSTRACT FROM AUTHOR]

The common liver fluke (Fasciola hepatica) causes the disease fasciolosis, which results in considerable losses within the global agri-food industry. There is a shortfall in the drugs that are effective against both the adult and juvenile life stages within the mammalian host, such that new drug targets are needed. Over the last decade the stem cells of parasitic flatworms have emerged as reservoirs of putative novel targets due to their role in development and homeostasis, including at host-parasite interfaces. Here, we investigate and characterise the proliferating cells that underpin development in F. hepatica. We provide evidence that these cells are capable of self-renewal, differentiation, and are sensitive to ionising radiation—all attributes of neoblasts in other flatworms. Changes in cell proliferation were also noted during the early stages of in vitro juvenile growth/development (around four to seven days post excystment), which coincided with a marked reduction in the nuclear area of proliferating cells. Furthermore, we generated transcriptomes from worms following irradiation-based ablation of neoblasts, identifying 124 significantly downregulated transcripts, including known stem cell markers such as fgfrA and plk1. Sixty-eight of these had homologues associated with neoblast-like cells in Schistosoma mansoni. Finally, RNA interference mediated knockdown of histone h2b (a marker of proliferating cells), ablated neoblast-like cells and impaired worm development in vitro. In summary, this work demonstrates that the proliferating cells of F. hepatica are equivalent to neoblasts of other flatworm species and demonstrate that they may serve as attractive targets for novel anthelmintics. Author summary: Liver fluke are parasitic worms that infect both livestock and humans worldwide, threatening food security and human health. Treatments against this disease-causing parasite are limited, and growing resistance to drugs is undermining the effectiveness of control strategies. Since drugs represent the only viable control option, it is crucial that new drugs are discovered through the identification and validation of new drug targets. Stem cells play important roles in the normal growth and repair processes of many organisms, but when these cells become dysregulated through mutation, they can drive the development of cancers. Stem cells of liver fluke may be attractive novel drug targets as disruption would affect worm survival and/or development within their host. In this research we describe the characteristics of liver fluke stem cells, such as their sensitivity to radiation and their ability to develop into new cell types (key stem cell features). We used radiation in combination with RNA sequencing to identify genes associated with the liver fluke stem cells. Finally, we used reverse genetics to reduce the expression of a gene associated with stem cells, which led to the loss of stem cells and reduced worm growth/development. These data provide evidence to support the exploitation of stem cells as a source of novel drug targets for liver fluke control. [ABSTRACT FROM AUTHOR]

Gene expression for Th1/Th2 cytokines (IL-4 and IFN-ɣ), regulatory cytokines (TGF-β and IL-10) and the transcriptional factor FoxP3 was analyzed in the liver and hepatic lymph nodes (HLN) from sheep immunized with partially protective and non-protective vaccine candidates and challenged with Fasciola hepatica. FoxP3 T cells were also evaluated by immunohistochemistry (IHQ). The most remarkable difference between the partially protected vaccinated (V1) group and the non-protected vaccinated (V2) group was a more severe expansion of FoxP3 T cells recorded by IHQ in both the liver and HLN of the V2 group as compared to the V1 group, whereas no differences were found between the V2 group and the infected control (IC) group. Similar results were recorded for FoxP3 gene expression although significant differences among V1 and V2 groups were only significant in the HLN, while FoxP3 gene expression was very similar in the V2 and IC groups both in the liver and HLN. No significant differences for the remaining cytokines were recorded between the V1 and V2 groups, but in the liver the V2 group shows significant increases of IFN-ɣ and IL-10 as compared to the uninfected control (UC) group whereas the V1 group did not. The lower expansion of FoxP3 T cells and lower increase of IFN-ɣ and IL-10 in the partially protected vaccinated group may be related with lower hepatic lesions and fluke burdens recorded in this group as compared to the other two infected groups. The most relevant change in regulatory cytokine gene expression was the significant increase of TGF-β in the liver of IC, V1 and V2 groups as compared to the UC group, which could be related to hepatic lesions. [ABSTRACT FROM AUTHOR]