Molecular evidence of Borrelia spp. in bats from Córdoba department, northwest Colombia.

Abstract Background The genus Borrelia is composed of two well-defined monophyletic groups that contain pathogens in humans: the Borrelia burgdorferi sensu lato complex (Bb), and relapsing fever (RF) group borreliae. Recently, a third group, associated with reptiles and echidnas has been described. In general, RF group borreliae use rodents as reservoir hosts; although Neotropical bats may also be involved as important hosts, with scarce knowledge of this association. The objective of this study was to detect the presence of Borrelia spp. DNA in bats from the department of Córdoba in northwest Colombia. Methods During September 2020 and June 2021, 205 bats were captured in six municipalities of Córdoba department, Colombia. Specimens were identified using taxonomic keys and DNA was extracted from spleen samples. A Borrelia specific real-time PCR was performed for the 16S rRNA gene. Fragments of the 16S rRNA and flaB genes were amplified in the positive samples by conventional PCR. The detected amplicons were sequenced by the Sanger method. Phylogenetic reconstruction was performed in Iqtree with maximum likelihood based on substitution model TPM3 + F + I + G4 with Bootstrap values were deduced from 1000 replicates. Sequences were submitted to phylogenetic analyses. Results Overall, 10.2% (21/205) samples were positive by qPCR; of these, 81% (17/21) and 66.6% (14/21) were positive for the 16S rRNA and flaB genes, respectively. qPCR-positive samples were then subjected to conventional nested and semi-nested PCR to amplify 16S rRNA and flaB gene fragments. Nine positive randomly selected samples for both genes were sequenced. The DNA of Borrelia spp. was detected in the insectivorous and fruit bats Artibeus lituratus, Carollia perspicillata, Glossophaga soricina, Phyllostomus discolor, and Uroderma sp. The 16S-rRNA gene sequences showed an identity of 97.66–98.47% with “Borrelia sp. clone Omi3”, “Borrelia sp. RT1S” and Borrelia sp. 2374; the closest identities for the flaB gene were 94.02–98.04% with “Borrelia sp. Macaregua”. For the 16S rRNA gene, the phylogenetic analysis showed a grouping with “Candidatus Borrelia ivorensis” and “Ca. African Borrelia” and for the flaB gene showed a grouping with Borrelia sp. Macaregua. The pathogenic role of the Borrelia detected in this study is unknown. Conclusions We describe the first molecular evidence of Borrelia spp. in the department of Córdoba in Colombia highlighting that several bat species harbor Borrelia spirochetes.