Conference Agenda

Fleas (Siphonaptera) are globally important blood-feeding ectoparasites that infest companion animals, livestock, and humans. They are vectors of bacterial pathogens such as Rickettsia and Bartonella. Yet, many flea species and their associated bacterial communities in Cambodia remain poorly characterised. This project aims to identify flea species parasitising dogs in Cambodia and characterise their bacteriome. Fleas collected from dogs across multiple Cambodian regions were morphologically identified using established dichotomous keys. Genomic DNA was extracted from individual fleas, and full-length 16S rRNA gene nanopore metabarcoding will be performed, following previously developed and validated workflows to characterise flea-borne bacteria (FBB). This flea bacteriome data will be analysed alongside previously generated dog blood bacterial profiles, using paired samples from the same individual hosts. Preliminary morphological work revealed that most fleas parasitising Cambodian dogs belong to the genus Ctenocephalides, with C. orientis predominating. Sequencing will confirm species identity and the diversity of FBB pathogens, potentially detecting well known zoonotic agents and novel taxa that conventional PCR-based approaches may fail to detect. Integrating flea species identification with bacteriome data and host blood infection status provides initial evidence on the potential vector role of canine fleas in Cambodia and identifies gaps for future surveillance in under-resourced settings.