Molecular Evidence of Novel Spotted Fever Group Species in Ticks from the Shingleback Skink () in Southern Western Australia.

Tick-borne infectious diseases caused by obligate intracellular bacteria of the genus are a growing global problem to human and animal health. Surveillance of these pathogens at the wildlife interface is critical to informing public health strategies to limit their impact. In Australia, reptile-associated ticks such as are the reservoirs for , the causative agent of Flinders Island spotted fever. In an effort to gain further insight into the potential for reptile-associated ticks to act as reservoirs for rickettsial infection, -specific PCR screening was performed on 64 ticks taken from shingleback skinks () located in southern Western Australia. PCR screening revealed 92% positivity for rickettsial DNA. PCR amplification and sequencing of phylogenetically informative rickettsial genes ( and ) suggested that the single rickettsial genotype detected represented a novel rickettsial species, genetically distinct from but closely related to and within the rickettsia spotted fever group (SFG). On the basis of this study and previous investigations, it would appear that spp. are endemic to reptile-associated tick species in Australia, with geographically distinct populations of the same tick species harboring genetically distinct SFG species. Further molecular epidemiology studies are required to understand the relationship between these diverse and their tick hosts and the risk that they may pose to human and animal health.