Analysis on the Molecular Detection of Rickettsia felis in Rhiphicephalus sangunieus Ticks Found in India

Tick borne diseases (TBDs) have remained a major concern throughout the world. The cases of TBDs have increased in past few years. Moreover, new emerging pathogens are being detected from ticks which have led the scientists to reveal more on this field. Among various pathogens transmitted from ticks, Spotted Fever Group rickettsia (SFGR) represents the huge number of new and emerging infectious pathogens but unfortunately has been neglected. Therefore, the study was carried out to detect SFGR from ticks collected from Gwalior. This report is a description Rickettsia felis which is a potential human pathogen detected in adult Rhiphicephalus sanguineus tick collected from dogs in Gwalior, India. For SFGR screening in the ticks, partial conserved region of Citrate Synthase (gltA) and Outer Membrane Protein B (rOmpB) genes were targeted. Both of the genes were amplified and thus indicated the presence of the rickettsial pathogen and its associated risk. Five percent (5.19%) of the screened ticks were PCR positive for SFGR. PCR amplicons were sequenced further. Additionally, Immunoflourescence assay (IFA) test was also done to double sure the result obtained. The sequencing result of gltA gene showed 97.87 percent similarity to R. felis (MH194353) and for rOmpB gene there was 99.47 percent similarity to R. felis (MG451836). This is the first report of R. felis DNA from Rh. sanguineus ticks in India. Further studies are required for clarity on the distribution of the R. felis in ticks and its transmission to human being. Thus, a comprehensive awareness is much needed for tackling rickettsial pathogen and subsequent steps leading to an improved health management in India.