东北边境地区啮齿动物中新埃立克体感染调查及groEL基因序列分析

目的了解东北地区啮齿动物新埃立克体(Candidatus Neoehrlichia mikurensis,Nm)感染及基因型分布情况。方法采用巢式PCR检测从辽宁省宽甸、吉林省集安林区及黑龙江省密山耕地捕获的啮齿动物中Nm groEL DNA,对阳性扩增产物进行测序和遗传进化分析。结果 PCR检测鼠脾标本共181份,阳性5份,阳性率为2.76%。不同地区及不同鼠种Nm检出阳性率无明显差异。遗传进化分析显示,从宽甸、集安黑线姬鼠和大林姬鼠检出的5份Nm groEL基因序列与俄罗斯亚洲地区以及我国东北地区Nm同源性最高,基因型为ClusterⅠ型。结论我国东北东部边境地区鼠类存在Nm感染,可能存在Nm自然疫源地。

Investigation on Candidatus Neoehrlichia mikurensis in rodents collected in forest area in the northeastern region of China

We investigated the Candidatus Neoehrlichia mikurensis(Nm) infection in wild rodents and to make clear the genetic characteristics of the agents from forest areas in northeastern China. Nested PCR amplification, following by sequence analysis, was carried out. The sequences of groEL gene fragment amplified from rodents were compared with corresponding part of the sequences deposited in GenBank. A total number of 181 rodents were tested, including 67 in Ji’an of Jilin Province, 66 in Kuandian of Liaoning Province and 48 in Mishan of Heilongjiang province. The positive rates were 2.76% (5/181), and for Jin’an, Kuandian and Mishan were 5.97% (4/67), 1.52% (1/66) and 0%(0/48) , respectively. There were not significant differences in different regions and in different mouse species for their infection with Nm. Phylogenetic analysis based on groEL nucleotide sequences revealed the 5 positive samples that correspond with genetype ClusterⅠ. It’s concluded that the nature focus of Nm did exist in the area of northeastern China.