江西省啮齿动物携带立克次体分子流行病学研究

Molecular epidemiological investigation of Rickettsiae in rodents in Jiangxi Province

目的调查江西省部分县区啮齿动物携带的立克次体。方法在江西省南丰县、铜鼓县、上犹县、浮梁县、上高县、上饶市广信区捕获啮齿动物,运用形态学结合分子生物学方法鉴定其种类。采用巢式PCR方法检测捕获的啮齿动物的脾脏组织样本中的柯克斯体属、斑点热群、东方体属和无形体属立克次体。结果捕获啮齿动物6种共393只,包括黑线姬鼠、褐家鼠、黄毛鼠、黄胸鼠、社鼠和臭鼩鼱,黑线姬鼠为优势鼠种(311/393)。从19只黑线姬鼠检出柯克斯体(6.11%),从2只黑线姬鼠检出东方体(0.64%),从1只黑线姬鼠检出斑点热群立克次体(0.32%)。对扩增阳性基因片段测序和对获得基因序列做同源性比对,结果浮梁县黑线姬鼠检出新塔拉萨维奇立克次体、恙虫病东方体、贝氏柯克斯体;铜鼓县和上饶市广信区黑线姬鼠检出贝氏柯克斯体;南丰县黑线姬鼠检出恙虫病东方体。除黑线姬鼠外,其它5种啮齿动物均未检出立克次体。结论江西省部分地区的黑线姬鼠携带贝氏柯克斯体、新塔拉萨维奇立克次体、恙虫病东方体等立克次体病原体,人群存在相关立克次体感染的风险,疾控和医疗机构应加强立克次体病的监测。

This study aimed to identify rickettsiae carried by rodents in different counties of Jiangxi province.Different species of rodents captured in the counties Nanfeng,Tonggu,Shangyou,Fuliang and Shanggao,as well as the Guangxin district of Shangrao in Jiangxi province,were identified through morphological characterization and molecular biology methods.The existence of Coxiella spp.,spotted fever group rickettsiae(SFGR),Orientia spp.and/or Anaplasma spp.was detected in these rodents with nested PCR.The positive fragments amplified from the DNA samples were sequenced,and the obtained sequences were used for phylogenetic analysis.A total of 393 rodents were captured,most of which were Apodemus agrarius,Rattus norvegicus,R.losea,R.flavipectus,R.confucianus and Suneus murinu.A.agrarius was the most prevalent species(311/393).The spleen DNA sample from each animal was detected with nested PCR with primers specific to each genus/group.Coxiella spp.,Orientia spp.and SFGR were detected in 19(6.11%),2(0.64%)and 1(0.32%)samples of A.agrarius,respectively.Phylogenetic analysis based on the obtained gene sequences showed that A.agrarius captured in Fuliang carried Candidatus Rickettsia tarasevichiae,O.tsutsugamushi or C.burnetii;A.agrarius captured in Tonggu and Shangrao carried C.burnetii;and A.agrarius captured in Nanfeng carried O.tsutsugamushi.Rickettsiae were not detected in other rodents except in A.agrarius.In conclusion,A.agrarius in certain counties of Jiangxi province carries C.burnetii,SFGR or O.tsutsugamushi.Efforts to monitor rickettsioses should be reinforced by local public health institutes and centers for disease control and prevention.