Phylogenetic analysis of Bartonella detected in rodent fleas in Yunnan, China.

Previous studies have demonstrated a diversity of Bartonella spp. in rodent populations in Yunnan Province, China. Although Bartonella spp. have been isolated from cat fleas and cattle ticks collected from their animal hosts, little is known about Bartonella carried by rodent fleas. In this study, Bartonella DNA was detected by polymerase chain reaction (PCR) in two of five species of rodent fleas. These included Xenopsylla cheopis and Ctenophthalmus lushuiensis, which were collected from Rattus tanezumi flavipectus and from the nests of voles, respectively, during 1997 from two sites in western Yunnan Province, China. Sequence analysis of the Bartonella citrate synthase gene (gltA) amplicons obtained from six of 65 grouped flea samples showed that Bartonella genetic variants were clustered in four groups. One from Xenopsylla cheopis was identical to Bartonella tribocorum, whereas the other three genotypes from Ctenophthalmus lushuiensis were related to the vole-associated Bartonella isolates and cat-associated Bartonella clarridgeiae. This is the first detection of this Bartonella variant from fleas in China. Therefore, further investigations are needed to clarify the distribution of Bartonella in rodents and their ectoparasites in China to define the role of these arthropods in the transmission routes of Bartonella.