Epidemiology and Control of Fascioliasis

Fascioliasis is a zoonotic trematode infection caused predominantly by Fasciola hepatica and, to a lesser extent, Fasciola gigantica. Its life cycle requires freshwater snails of the family Lymnaeidae as intermediate hosts and a variety of aquatic plants or contaminated water as vehicles for the infective metacercarial stage. Humans and grazing ruminants acquire infection through ingestion of metacercariae attached to vegetation such as watercress, or via drinking water. The disease exhibits a worldwide distribution, with hotspots in Andean South America, parts of Africa and Asia, and temperate regions of Europe. Clinical manifestations range from acute hepatic injury during larval migration to chronic biliary fibrosis, with substantial impacts on human health, agricultural productivity and rural livelihoods. Control strategies combine targeted chemotherapy with triclabendazole or alternative flukicides, improved diagnostics for early detection, snail control measures, and community education to reduce exposure to contaminated water and plants. The emergence of drug resistance, driven by polymorphism and gene duplication in parasite populations, underscores the need for novel interventions. Predictive modelling of transmission under changing climate and land-use patterns informs surveillance and resource allocation. Integrated One Health approaches that unite veterinary, environmental and public health initiatives have demonstrated success in reducing prevalence through environmental management, strategic deworming and socio-behavioural change. Advances in molecular and spatial epidemiology now offer refined tools to map transmission, monitor flukicide efficacy and prioritise vaccine development, thereby reinforcing sustainable control efforts at the interface of human, animal and ecosystem health.

Research from Nature Portfolio

Spatial transcriptomics applied to Fasciola hepatica has produced a high-resolution atlas of gene expression across eight distinct parasite tissues. This work has identified tissue-specific profiles of vaccine candidate antigens, such as Ly6 family proteins, alongside key drug resistance determinants including glutathione S-transferases and ABC transporters. The atlas has further revealed the tegumental protein kinase PKCβ as a promising molecular target: small-molecule inhibition of PKCβ induces parasite death ex vivo. By linking spatial gene expression to functional assays, this study provides an unprecedented molecular framework for prioritising novel drug and vaccine candidates and for understanding mechanisms of resistance at the organ-system level.

Epidemiology and Control of Fascioliasis publication trend

The graph below shows the total number of articles in epidemiology and control of fascioliasis across all publications each year (not limited to Nature Index journals).

Technical terms

Metacercariae: encysted larval stage of Fasciola spp. that attaches to aquatic plants or floats in water, infectious to definitive hosts.

Intermediate host: freshwater snail that supports larval development of Fasciola between egg hatching and metacercaria formation.

Anthelmintic: chemical agent used to eliminate helminth parasites, including triclabendazole and novel flukicides.

Spatial transcriptomics: technique mapping gene expression patterns to precise tissue locations within an organism.

Tegument: outer syncytial surface layer of trematode parasites involved in nutrient uptake, immune modulation and drug target exposure.

References

1. Spatial transcriptomics of a parasitic flatworm provides a molecular map of drug targets and drug resistance genes. Nature Communications (2024).
2. Modified Hederagenin Derivatives Demonstrate Ex Vivo Anthelmintic Activity against Fasciola hepatica. Pharmaceutics (2023).
3. Human fascioliasis infection sources, their diversity, incidence factors, analytical methods and prevention measures. Parasitology (2018).
4. Evaluation of the Performance of Five Diagnostic Tests for Fasciola hepatica Infection in Naturally Infected Cattle Using a Bayesian No Gold Standard Approach. PLOS ONE (2016).
5. The Fasciola hepatica genome: gene duplication and polymorphism reveals adaptation to the host environment and the capacity for rapid evolution. Genome Biology (2015).
6. Predicting Impacts of Climate Change on Fasciola hepatica Risk. PLOS ONE (2011).
7. Fascioliasis: An Ongoing Zoonotic Trematode Infection. BioMed Research International (2015).