Microbial Pathogen Community in Ornithodoros lahorensis (Acari: Argasidae) in China

The prevalence of tick-borne bacterial and viral diseases, which pose a serious threat to human and livestock health, is increasing worldwide. At present, only a limited number of tick-borne pathogens have been reported, and no analysis of the microbial pathogen community in ticks has been carried out. We sequenced the viral metagenome of Ornithodoros lahorensis species of ticks from the Chinese mainland and identified 390 RNA viruses with unique microbial compositions. A total of 992 assembled viral transcriptomes revealed the breadth and diversity of the genome structure of tick-borne viruses, reflecting the importance of ticks as RNA viral pools. We analyzed the phylogeny of different virus families to investigate virus evolution and found that the most diverse tick-associated viruses belonged to the family Siphoviridae, which diverged earlier in evolutionary time than other arboviruses. There were only a few tick-specific viruses, whereas the number of vertebrate-infecting viruses in ticks was greater. We hope that our virus sequencing dataset will facilitate future important research on viruses carried by ticks that can infect vertebrates.