Conference Agenda

Parasitic nematodes of the family Onchocercidae have co-evolved with vertebrate hosts for millions of years. Although morphology has traditionally underpinned species identification, many taxa are cryptic and difficult to distinguish, limiting accurate diagnosis. Clinically important genera include Dirofilaria, which causes heartworm disease in dogs and occasional zoonotic infections in humans. However, substantial gaps remain in our understanding of other Dirofilaria species and genotypes and their impacts on host health. This study aimed to generate a comprehensive morphological and molecular resource for a newly identified Dirofilaria species. Using long-read PacBio and Hi-C sequencing, we assembled and characterised both mitochondrial and nuclear genomes. The nuclear genome comprises four autosomes and one sex-linked scaffold, encoding 9,658 genes. Comparative analyses with related filarial nematodes revealed conserved chromosomal structure alongside lineage-specific rearrangements. We identified 881 predicted excretory/secretory proteins enriched in immune-related pathways such as proteolysis, lysosomal function and antigen presentation. Notably, 26% of these proteins were unique, many associated with host–parasite interactions, immune evasion and metabolic adaptation. This genome fills a key gap in filarial resources and supports advances in epidemiology, host adaptation studies and diagnostic development.

Understanding how biological processes and interactions unfold within intact organisms requires approaches that link anatomical organisation with spatially resolved molecular information. Although spatially integrated analyses have transformed vertebrate biology, comparable frameworks remain limited for many non-model invertebrates despite their ecological and biomedical importance. Freshwater snails represent a particularly informative system, functioning both as key components of aquatic ecosystems and as intermediate hosts for numerous parasitic organisms. Here we establish an integrated spatial–molecular analytical framework for investigating biological processes within a lymnaeid snail using infection with the liver fluke Fasciola hepatica as a model host–parasite system. The approach combines whole-organism three-dimensional imaging using X-ray microcomputed tomography with serial histopathology, bulk RNA sequencing and spatial transcriptomic analysis. Integrating these complementary datasets enables parasite distribution to be examined within the anatomical structure of the host while simultaneously linking tissue pathology with spatially resolved gene transcription patterns. Beyond the present host–parasite system, this framework provides a foundation for investigating a broad range of biological processes in freshwater snails, including environmental responses, neurobiology and host–parasite interactions.