Tick-borne pathogens in Mongolian ticks: The high prevalence of Rickettsia raoultii and its public health implications

In Mongolia, a substantial segment of the population is engaged in pastoralism, leading to frequent interactions with livestock and heightened exposure to tick-infested environments. Consequently, ticks and the endemic tick-borne pathogens (TBPs) they harbor present significant health threats. In May 2021, we conducted a study to evaluate the prevalence of 9 TBPs in ticks collected from four regions in Mongolia: Uvurkhangai, Tuv, Bayan-Ulgii, and Khentii. The pathogens surveyed included Anaplasma, Rickettsia, Bartonella, Borrelia, Ehrlichia, Babesia, Toxoplasma, Theileria, and lumpy skin disease virus. Molecular analysis of 1142 ticks revealed that, although the majority of TBPs were not detected, 89.1 % of the ticks were positive for Rickettsia. Genetic characterization using the 16S rRNA and gltA genes identified the pathogen identified the pathogen Rickettsia raoultii. Species identification indicated a predominance of Dermacentor nuttalli (70.0 %) and Dermacentor silvarum (30.0 %). These findings highlight the extensive prevalence of R. raoultii in Mongolia and underscore the urgent need for heightened awareness and preventive measures due to the high level of interaction between livestock and humans. The genetic similarity of R. raoultii sequences to those found in neighboring countries suggests potential cross-border transmission, underscoring the importance of conducting similar research in surrounding regions. This study advances our understanding of the epidemiology of tick-borne diseases in Mongolia and can inform public health strategies aimed at mitigating the risks associated with these infections.