云南省西双版纳州鼠型斑疹伤寒暴发的调查(英文)

目的 阐明云南省西双版纳州鼠型斑疹伤寒的流行状况。方法 收集云南省鼠型斑疹伤寒病例资料。于2011年6-9月在西双版纳地区采集鼠型斑疹伤寒临床诊断病例的急性期和恢复期血清,并在发病地区的居民区捕鼠,采集鼠血液和脾脏标本。用间接免疫荧光试验检测患者和鼠血清中的鼠型斑疹伤寒立克次体的IgM和IgG抗体,用实时荧光PCR试验检测急性期病人血块和鼠脾脏中的鼠型斑疹伤寒立克次体热休克蛋白基因(groEL gene)。结果 2004-2011年,云南省共报告鼠型斑疹伤寒病例8 361例,所有州(市)均有病例报告,其中西双版纳州发病数和发病率最高(86.6/10万),占全省总病例数的73.1%(6 111/8 361)。发病数具有逐年上升之势,全年均有病例发生,6-10月为主要流行期。2011年云南省共报告鼠型斑疹伤寒1 369例,其中西双版纳州报告病例1 157例,发病率为102.10/10万,病例数占云南省病例数的84.51%。勐海县、勐腊县和景洪市分别占全州病例数的79.95%(n=925, 278.74/10万)、18.06%(n=209,74.10/10万)和1.99%(n=23,4.42/10万),勐海县发病率显著高于勐腊县(χ²=346.3, P<0.001)和景洪市(χ²=1369, P<0.001)。对2011年的80例病人进行了实验室检测,在80例急性期病人血清标本中有 63例为IgM抗体阳性;75例病人双份血清标本中有61例的恢复期血清滴度高于急性期4倍及以上;80例患者急性期血块中有8例为PCR阳性。依据实验室诊断标准,74例被确诊为鼠型斑疹伤寒,其中血清学诊断73例(包含7例同时为分子诊断),分子诊断1例,临床诊断和实验室检测符合率为92.50%(74/80)。黄胸鼠血清鼠型斑疹伤寒立克次体IgG抗体阳性率为14.0% (14/100),脾脏的PCR阳性率为9.0% (9/100)。结论 西双版纳州存在较为严重的鼠型斑疹伤寒流行,其中勐海县流行最为严重。

Murine typhus in Xishuangbanna Prefecture,Yunnan Province,China

In recent years, there has been high prevalence of murine typhus in Yunnan Province, People's Republic of China. A large outbreak of murine typhus occurred in Xishuangbanna Prefecture, Yunnan Province in 2010. However, not all cases were confirmed by laboratory assays; therefore, field epidemiologic and laboratory investigations of murine typhus in Xishuangbanna Prefecture were conducted in 2011. Blood samples were collected from clinical diagnostic cases at the acute and convalescence stages of murine typhus in Xishuangbanna Prefecture, Yunnan Province, from June to September of 2011, and blood and spleen samples were collected from mice sharing the same habitats as the patients. Immunofluorescence assays were used to test for the presence of IgM and IgG antibodies against Rickettsia typhi in sera from patients and mice. Real-time PCR was used to detect the groEL gene of R. typhi in blood clots from patients at the acute stage and in spleen tissue from mice. A total of 1 157 clinically diagnosed murine typhus cases occurred in Xishuangbanna Prefecture, Yunnan Province in 2011, with an incidence of 102.10/100 000. Of these cases, 80 were investigated by laboratory assays and 74 of 80 patients were confirmed to have murine typhus. The coincidence rate between the clinical diagnosis and laboratory detection was 92.50%. The positivity rate for IgG antibodies against R. typhi was 14.0% (14/100) for Rattus flavipectus, while the rate by PCR was 9.0% (9/100). That laboratory diagnoses confirmed that the severity of the murine typhus outbreak in Xishuangbanna cannot be ignored. The distribution of host animals transmitting R. typhi underscores this conclusion.