2000年中国结核病流行病学抽样调查菌株分子流行病学特征

Molecular epidemical characteristics of Mycobacterium tuberculosis strains from the nationwide random survey for the epidemiology of tuberculosis in China, 2000

目的 从分子流行病学角度探讨中国结核分枝杆菌的分布特征。方法 样本的获得采用全国范围等比例分层整群随机抽样 ;构建以IS6 110RFLPDNA指纹方法和以DR为基础的SpoligotypingDNA指纹方法 ;采用Gelcompare4 1软件对DNA指纹图谱进行数字化 ,比较其相似性 ;同时应用该软件行聚类 (cluster)分析 ;用 χ2 检验比较不同组别病人的分离菌株成簇率 (clustering)的差别 ,利用公式 1和 2计算影响结核病近期传播的危险因素 (OR值 )。结果 共获得 4 0 2株可进行DNA指纹分析的结核分枝杆菌 ;其中 5 0 75 % (2 0 4 / 4 0 2 )为“北京基因型”菌株 ;发现 3簇指纹图谱相同的菌株 ,其中 1簇对应的病人来源于同一家庭 ;分组统计显示 :男性组与女性组、年龄≥ 4 0岁组与<4 0岁组成簇率之间差异有显著性 (P <0 0 5 ) ,近期传播的危险因素男性为OR1:2 0 4 95 %CI(1 0 7～ 3 96 ) ,OR2 :4 96 95 %CI(2 77～ 9 0 0 ) ;<4 0岁为OR1:1 6 895 %CI(1 0 1～ 2 80 ) ,OR2 :1 30 95 %CI(0 2～ 0 4 4 ) ,其他各组之间差异无显著性 (P >0 0 5 )。结论 北京基因型结核分枝杆菌在中国呈较高水平的流行 ;男性和年长 (≥ 4 0岁 )可能为结核病近期传播的危险因素。利用结核分枝杆菌的DNA指纹图谱 ,可以实现结核分枝杆菌传染源?

Objective To explore the epidemical distribution characteristics of Mycobacterium tuberculosis isolated from China. Methods The M. tuberculosis strains were gained by multi-stratified grouping random sampling method from the nationwide random survey for the epidemiology of tuberculosis in China, 2000, and analyzed by IS6110-based RFLP and DR-based Spoligotyping DNA fingerprinting. These fingerprinting patterns were transferred into digital data and compared each other, and clustered by Gel compar 4.1 Software. The clustering values in different TB patients were compared by χ2 test and the risk factors for recent transmission were calculated by Odd Ratios. Results Two hundreds and four of 402 M. tuberculosis strains from this survey were determined to be “Beijing Genotype” M. Tuberculosis strain by DNA fingerprinting analysis. Three clusters M. tuberculosis strains sharing identical fingerprint pattern were found, including one cluster belong to a same family. There were significant difference in clustering values between female and male, and younger(<40 years old ) and elder (≥40 years old) (P<0.05). Odds Ratio 1 showed youth [1.68 95%CI(1.01-2.80)] and male [2.04 95%CI(1.07-3.96)],but Odds Ratio 2 showed youth [0.3 95%CI(0.2-0.44)] and male [4.96 95%CI(2.77-9.00)]. Conclusion M. tuberculosis strains of Beijing Genotype are prevailing in China at present. Male and elder were shown to be significant risk factors for recent transmission. The infection source of M. tuberculosis can be traced by DNA fingerprinting.