Cat fleas (Ctenocephalides felis) from cats and dogs in New Zealand: Molecular characterisation, presence of Rickettsia felis and Bartonella clarridgeiae and comparison with Australia

- Common dispersal of cat fleas across both the geographical (Tasman Sea) and climate scale.
- Haplotypes of mtDNA of Ctenocephalides felis (cat flea) identical or near identical between southern Australia and New Zealand.
- Ctenocephalides felis (cat flea) dominant on dogs and cats in New Zealand.
- New Zealand cat fleas carried Rickettsia felis (5.3%) and Bartonella clarridgeiae (18.4%).

The cat flea (Ctenocephalides felis) is the most common flea species parasitising both domestic cats and dogs globally. Fleas are known vectors of zoonotic pathogens such as vector borne Rickettsia and Bartonella. This study compared cat fleas from domestic cats and dogs in New Zealand's North and South Islands to Australian cat fleas, using the mitochondrial DNA (mtDNA) marker, cytochrome c oxidase subunit I and II (cox1, cox2). We assessed the prevalence of Rickettsia and Bartonella using genus specific multiplexed real-time PCR assays. Morphological identification confirmed that the cat flea (C. felis) is the most common flea in New Zealand. The examined fleas (n = 43) at cox1 locus revealed six closely related C. felis haplotypes (inter-haplotype distance 1.1%) across New Zealand. The New Zealand C. felis haplotypes were identical or near identical with haplotypes from southern Australia demonstrating common dispersal of haplotype lineage across both the geographical (Tasman Sea) and climate scale. New Zealand cat fleas carried Rickettsia felis (5.3%) and Bartonella clarridgeiae (18.4%). To understand the capability of C. felis to vector zoonotic pathogens, we determined flea cox1 and cox2 haplotype diversity with the tandem multiplexed real-time PCR and sequencing for Bartonella and Rickettsia. This enabled us to demonstrate highly similar cat fleas on cat and dog populations across Australia and New Zealand.

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