Molecular Detection and Genetic Diversity of Bat‐Associated Bartonella spp. in Bat Ectoparasites Collected From Ratchaburi Province, Thailand

INTRODUCTION: Bats are known to harbour Bartonella bacteria, which can be found in several species of bats. Various ectoparasites can infest bats and harbour the bacteria, serving as important vectors for diverse Bartonella species. This study aimed to assess the prevalence and diversity of Bartonella spp. in bat ectoparasites, as well as to identify the species of ectoparasites involved. METHODS: Bat ectoparasites were collected from four species of insectivorous bats in Ratchaburi, central Thailand. The ectoparasites were identified using the Cytochrome oxidase subunit I (COI) gene (bat flies, fleas and bugs) and the 16S rRNA gene (mites and ticks). Bartonella was screened and sequenced using the rpoB and gltA genes, followed by phylogenetic relationships and haplotype diversity analysis. RESULTS: A total of 106 bat ectoparasites were identified, including Phthiridium sp., Raymondia sp., Nycteribia sp. (bat flies), and other ectoparasites such as Spinturnix sp. (mites), Cimex sp. (bugs), Ixodes sp. (ticks) and Orchopeas sp. (fleas). The detection of Bartonella, based on rpoB and/or gltA, was positive in 48 specimens (45.28%) of Phthiridium sp. (32.08%, n = 34), Raymondia sp. (9.43%, n = 10), Nycteribia sp. (1.89%, n = 2), Spinturnix sp. (0.94%, n = 1) and Cimex sp. (0.94%, n = 1). Phylogenetic analysis of Bartonella rpoB sequences revealed the presence of six distinct lineages (I-VI), whereas five lineages (I-V) were identified based on gltA sequences. Genetic diversity analysis showed high diversity, shared between bat hosts and their ectoparasites. CONCLUSIONS: This study represents the first report of Bartonella spp. detected in bat ectoparasites in Thailand, thereby providing novel molecular evidence of Bartonella diversity and circulation within bat ectoparasite populations.