云南省曲靖市啮齿动物的立克次体血清学和分子流行病学调查

Seroprevalence and molecular biological investigation of commonly known Rickettsiaspecies in rodents in Qujing Prefecture,Yunnan Province,China

目的调查云南省曲靖市啮齿动物感染立克次体状况。方法用鼠笼法捕鼠,采集鼠血清和脾脏。用间接免疫荧光试验(IFA)检测鼠血清中7种常见立克次体的IgG抗体;用巢氏PCR方法检测鼠脾中嗜单核细胞埃立克体和嗜吞噬细胞无形体16SrRNA基因片段部份序列。结果 2012年7-9月在曲靖市捕获啮齿动物3种592只,褐家鼠(Rattus norvegicus)和黄胸鼠(Rattus flavipectus)构成比分别为61.49%和35.47%。鼠血清中贝氏柯克斯体(Coxiella burentii)、莫氏立克次体(Rickettsia typhi)、恙虫病东方体(Orientia tsutsugamushi)、西伯利亚立克次体(Rickettsia sibirica)、嗜吞噬细胞无形体(Anaplasma phagocytophilum)和嗜单核细胞埃立克体(Ehrlichia chaffeensis)的抗体阳性率依次为21.45%、7.60%、7.09%、3.38%、1.18%和0.51%;未检测到猫立克次体(Rickettsia felis)抗体。从5份褐家鼠脾脏标本中检测到16SrRNA基因序列,同源性和进化分析表明,1株为嗜吞噬细胞无形体,4株为莫氏立克次体。结论曲靖市啮齿动物中存在莫氏立克次体和人粒细胞无形体流行,褐家鼠可能是主要宿主;同时还存在恙虫病东方体、贝氏柯克斯体、斑点热立克次体和埃立克体的感染。当地疾控和医疗机构应加强立克次体病的监测。

To investigated the prevalence of Rickettisaspecies in rodents in Qujing Prefecture,Yunnan Province,cage traps were used to capture rodents alive and sera and spleens were collected.Indirect immunoinfluscent assay（IFA）was used to detect the presence of IgG antibodies induced by 7bacterial pathogenic agents,including the commonly known Rickettisaspecies of R.typhi,R.sibirica,R.felis,and Orientia tsutsugamushi.Nested PCR was employed to amplify the 16 SrRNA gene for detecting Anaplasma phagocytophilumand Ehrlichia chaffeensis.A total of 592 rodents were collected between July-September,2012.Rattus norvegicus and Rattus flavipectus accounted for 61.49%（364）and 35.47%（210）,respectively.Positive rates of Coxiella burentii,R.typhi,O.tsutsugamushi,R.sibirica,A.phagocytophilum and E.chaffeensis antibodies were 21.45%,7.60%,7.09%,3.38%,1.18% and0.51%,respectively.No antibody of R.felis was detected.The partial sequence of the targeted 16 SrRNA was detected from 5spleens specimens of Rattus norvegicus.Phylogenetic analyses showed that 1amplicon was A.phagocytophilum and 4were R.typhi.A.phagocytophilumand R.typhi existed in local rodents and Rattus norvegicus is the potential reservoir host.The prevalence of Coxiella burentii,O.tsutsugamushi,R.sibirica and E.chaffeensis were also suggested.Efforts to survey these pathogenic agents should be reinforced by local public health and medical sectors.