Detection of Bartonella alsatica in European wild rabbit and their fleas (Spilopsyllus cuniculi and Xenopsylla cunicularis) in Spain

BACKGROUND: Bartonella alsatica has been formerly isolated from the blood of wild European rabbit (Oryctolagus cuniculus) and identified as causative agent of human endocarditis and lymphadenitis. Fleas are known biological vectors for Bartonella sp. This report details the specific detection of B. alsatica in three flea species commonly associated with the European wild rabbit in Southern Iberian Peninsula (Odontopsyllus quirosi, Spylopsyllus cuniculi and Xenopsylla cunicularis). METHODS: In the present study we have tested the presence of Bartonella alsatica in 26 European wild rabbit specimens and the fleas that they carrying at the moment of capture. Together to rabbits, captured from different localities of Andalusia (Jaen, Granada and Cordoba provinces), we evaluated three of fleas species that parasitize it usually using molecular techniques [PCR amplification and sequencing of intergenic transcribed spacer (ITS) 16S-23S rRNA]. RESULTS: Over a sample of 26 wild rabbits carrying fleas, positive PCR amplicons for B. alsatica were obtained from 10 rabbits. All positive flea pools for B. alsatica were collected from positive rabbits [33.33% (8/24 pools) of S. cuniculi, 33.33% (5/15 pools) of X. cunicularis and 0% (0/7 pools) of O. quirosi]. In three positive rabbits, a pool of S. cuniculi and two pools of X. cunicularis respectively were negative. After sequencing, only B. alsatica (Genbank accession AF312506) was found in the rabbits sampled as well as in S. cuniculi and X. cunicularis within the respective fleas. CONCLUSIONS: This research confirms the implication of two pulicidae flea species, S. cuniculi and X. cunicularis in the maintenance of infection by B. alsatica in wild rabbit populations throughout the year. The zoonotic character of this bartonellosis emphasizes the need to alert public health authorities and the veterinary community for the risk of infection.