Molecular Detection and Phylogenetic Analyses of Diverse Bartonella Species in Bat Ectoparasites Collected from Yunnan Province, China

Abstract

<i>Bartonella</i> species has been validated as blood-borne bacteria in mammals and has a substantial opportunity to be harbored by a variety of hematophagous arthropod vectors. Bats, along with their ectoparasites, are recognized worldwide as one of the natural reservoir hosts for these bacteria. However, there have been few investigations of <i>Bartonella</i> bacteria toward a broad range of obligated bat ectoparasites in China. Here, molecular detection of <i>Bartonella</i> species was performed to survey the infection among bat ectoparasites and follow-up phylogenetic analyses to further characterize the evolutionary relationships of the genus. A total of 434 bat ectoparasites involving four types of arthropods, namely, bat mites, bat tick, bat fleas, and bat flies (further divided into traditionally fly-like bat flies and wingless bat flies) were collected in 10 trapping sites in Yunnan Province, southwestern China. <i>Bartonella</i> was detected by PCR amplification and sequencing through four gene target fragments (<i>gltA</i>, <i>ftsZ</i>, <i>rpoB</i>, and ITS). Accordingly, diverse <i>Bartonella</i> species were discovered, including both the validated species and the novel genotypes, which were characterized into several geographical regions with high prevalence. Phylogenetic analyses based on <i>gltA</i> and multi-locus concatenated sequences both demonstrated strong phylogeny-trait associations of <i>Bartonella</i> species from bats and their parasitic arthropods, suggesting the occurrence of host switches and emphasizing the potential connecting vector role of these ectoparasites. Nevertheless, the maintenance and transmission of <i>Bartonella</i> in both bat and hemoparasite populations have not been fully understood, as well as the risk of spillage to humans, which warrants in-depth experimental studies focusing on these mammals and their ectoparasites.