Background Fasciola hepatica, a globally distributed helminth, causes fasciolosis, a disease with significant health and economic impacts. Variability in triclabendazole (TCBZ) efficacy and emerging resistance are remaining challenges. Evidence suggests that the gut microbiome influences host-helminth interactions and is associated with anthelmintic effects, but its association with human F. hepatica infection and TCBZ efficacy is not well understood. Methods In this study, we investigated the relationship between Fasciola hepatica infection and the gut microbiome through metagenomic shotgun sequencing of 30 infected and 60 age- and sex-matched uninfected individuals from Peru. Additionally, we performed a longitudinal analysis to evaluate microbiome dynamics in relation to TCBZ treatment response. Results and discussion Infection was associated with specific microbial taxonomic and func...

Triclabendazole (TCBZ) resistance is an emerging problem in fascioliasis that is not well understood. Studies including small numbers of parasites fail to capture the complexity of susceptibility variations between and within Fasciola hepatica populations. As the first step to studying the complex resistant phenotype–genotype associations, we characterized a large sample of adult F. hepatica with diverging TCBZ susceptibility. We collected parasites from naturally infected livestock slaughtered in the Cusco and Cajamarca regions of Peru. These parasites were exposed to TCBZ sulfoxide (TCBZ.SO) in vitro to determine their susceptibility. We used a motility score to determine the parasite’s viability. We titrated drug concentrations and times to detect 20% non-viable (susceptible conditions) or 80% non-viable (resistant conditions) parasites. We exposed 3348 fully motile parasites to s...

Triclabendazole (TCBZ) is the primary treatment for fascioliasis, a global foodborne zoonosis caused by Fasciola hepatica. Widespread resistance to TCBZ (TCBZ-R) in livestock and a rapid rise in resistant human infections are significant concerns. To understand the genetic basis of TCBZ-R, we sequenced the genomes of 99 TCBZ-sensitive (TCBZ-S) and 210 TCBZ-R adult flukes from 146 bovine livers in Cusco, Peru. We identify genomic regions of high differentiation (FST outliers above the 99.9th percentile) that encod genes involved in the EGFR-PI3K-mTOR-S6K pathway and microtubule function. Transcript expression differences are observed in microtubule-related genes between TCBZ-S and -R flukes, both without drug treatment and in response to treatment. Using only 30 SNPs, it is possible to differentiate between TCBZ-S and -R parasites with ≥75% accuracy. Our outlier loci are distinct from t...

Fascioliasis is a parasitic infection caused by Fasciola spp., primarily affecting ruminant animals. These digenean flatworms cause severe liver damage in their hosts, resulting in substantial economic losses within the livestock industry. Human fascioliasis is an emerging public health concern, with an estimated global prevalence of 2.6 million cases. Infection in humans typically occurs through the ingestion of aquatic vegetation or water contaminated with metacercariae. Triclabendazole (TCBZ) remains the only drug recommended by WHO for the treatment of human fascioliasis and is widely used in livestock. However, the increasing prevalence of TCBZ resistance in livestock, along with reports of TCBZ-resistant human infections, poses a growing challenge to disease control. Although it has been suggested that resistant livestock infections may contribute to the emergence of resistance in ...

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 pro...