Abstract:
Japanese spotted fever (JSF) is caused by Rickettsia japonica, mainly vectored by hard ticks. However, whether R. japonica can be transmitted by other arthropods remains unknown. Moreover, it is of interest to investigate whether other Rickettsia species cause spotted fever in endemic areas. In this study, a survey of Rickettsia species was performed in hematophagous arthropods (mosquitoes, tabanids, and ticks) from endemic areas for JSF in Hubei Province, central China. The results showed that the diversity and prevalence of Rickettsia species in mosquitoes are low, suggesting that mosquitoes may not be the vector of zoonotic Rickettsia species. A novel Rickettsia species showed a high prevalence (16.31%, 23/141) in tabanids and was named \"Candidatus Rickettsia tabanidii.\" It is closely related to Rickettsia from fleas and mosquitoes; however, its pathogenicity in humans needs further investigation. Five Rickettsia species were identified in ticks. Rickettsia japonica, the agent of JSF, was detected only in Haemaphysalis longicornis and Haemaphysalis hystricis, suggesting that they may be the major vectors of R. japonica. Notably, two novel species were identified in H. hystricis ticks, one belonging to the spotted fever group and the other potentially belonging to the ancestral group. The latter one named \"Candidatus Rickettsia hubeiensis\" may provide valuable insight into the evolutionary history of Rickettsia.
摘要:
日本斑点热(JSF)是由日本立克次体引起的,主要由硬蜱矢量化。然而,R.japonica是否可以通过其他节肢动物传播仍然未知。此外,研究其他立克次体是否会在流行地区引起斑点热。在这项研究中,对吸血节肢动物(蚊子,tabanids,和蜱)来自湖北省JSF流行区,中国中部。结果表明,蚊子体内立克次体物种的多样性和流行率较低,这表明蚊子可能不是人畜共患立克次体物种的媒介。一种新的立克次体物种表现出很高的患病率(16.31%,23/141)在烟草中,被命名为“立克次体”。“它与跳蚤和蚊子的立克次体密切相关;然而,其在人类中的致病性需要进一步研究。在蜱中鉴定出五种立克次体。日本立克次体,JSF的代理人,仅在长骨和囊状血栓菌中检测到,这表明它们可能是粳稻的主要载体。值得注意的是,在H.hystricis蜱中发现了两个新物种,一个属于斑点热组,另一个可能属于祖先组。后者名为“湖北念珠菌立克次体”,可能为立克次体的进化史提供有价值的见解。