Survey of pathogenicity of Rickettsia species on dogs and distribution of Rickettsia species in Hokkaido.

应用聚合酶链式反应和间接免疫荧光法对北海道地区感染犬类的犬和硬体进行立克次体种类检测。用聚合酶链式反应在一份犬血标本中检测到立克次体，并对扩增产物进行了序列分析，结果表明所获得的序列与猫立克次体密切相关。血清学调查显示，8.9%的狗对立克次体有较高的血清效价，这表明北海道有大量的狗暴露于立克次体。在被狗感染的硬体中，24%携带立克次体，这表明狗可能将硬壳中的立克次体带到人类环境中。在狗身上检测到与立克次体密切相关的立克次体，在感染松鼠的跳蚤中也检测到了立克次体，这可能表明跳蚤在立克次体向狗的传播中起到了一定的作用。

Dogs and ticks infected with dogs in Hokkaido were examined for Rickettsia species using PCR and IFA. The rickettsial agent was detected by PCR in one canine blood sample, and the sequence analysis of the PCR product showed that the obtained sequence was closely related to R. felis. Serological survey showed that 8.9% of dogs had high serum titer to Rickettsia species, which revealed that large number of dogs in Hokkaido was exposed to rickettsial agents. Twenty-four percent of ticks infested with dogs harbored rickettsial agents, which suggested that dogs may bring rickettsial agents in ticks to the human environment.Rickettsia species closely related to the rickettsial agent detected in dog was also detected in the flea infested with the squirrel, Sciurus vulgaris orientis, which may suggest that the flea has some role in transmission of rickettsiae to dogs.