Unveiling the Presence of Coxiella-like bacteria in Rhipicephalus microplus Ticks from Punjab, North India: A 16S...

In this study, using 16S rRNA gene-based metagenomics, we aimed to determine the presence of infectious bacteria in the ticks collected from Punjab state in north India. Tick samples were collected from the domesticated animals from the Patiala, Ropar, and Mohali districts of Punjab, India from February 2022- April 2022. DNA was extracted, and the library was prepared by targeting the V3-V4 hypervariable region of the 16S rRNA gene. The sequencing was conducted in Illumina using the 300 bp paired-end chemistry. Eight tick samples were analyzed from the Patiala, Ropar and Mohali districts of Punjab, India, revealing a diverse range of bacterial species within the tick microbiome. Seven out of eight samples were found to harbour Coxiella-like bacteria (46-181,607 reads; closely related to C. burnetii based on 16S rRNA [V3-V4] sequence similarity), indicating their abundance in the tick population. Furthermore, the analysis uncovered the presence of other pathogenic bacterial genera, including Staphylococcus, Streptococcus, Corynebacterium, Enterococcus, Pseudomonas, Bordetella, and Micrococcus in the tick microbiome, highlighting the abundance and diversity of infectious organisms within ticks. 16S rRNA gene-based metagenomics enables valuable insights into infectious agents in disease-transmitting vectors. Coxiella-like bacteria were found to be predominant bacterial species in the tick microbiomes in this study. The public health significance of this finding in animals and humans needs to be explored in this region. However, as 16S rRNA sequencing offers limited resolution for distinguishing closely related taxa, further confirmation using additional loci or whole-genome sequencing is warranted.