Xu Biao, Hu Yi, Wang Wei-bing, Jiang Wei-li
Department of Epidemiology, School of Public Health, Fudan University, Shanghai 200032, China.
Zhonghua Liu Xing Bing Xue Za Zhi. 2010 May;31(5):525-9.
To investigate the contribution of recent transmission in the epidemic of drug-resistant Mycobacterium tuberculosis (M.TB) and related factors from biomedical and social-demographic perspectives in the Eastern rural areas of China.
Identified by proportion method of drug susceptibility test, 223 drug resistant M.TB isolates and their hosts were included in the present study. These drug resistant tuberculosis isolates were first genotyped by Mycobacterial Interspersed Repetitive Units (MIRU), and those isolates with identical MIRU genotype were further classified by IS6110 restricted fragment polymorphism (RFLP). 'Cluster' was defined as two patients' M. TB isolates harboring the identical MIRU genotype and IS6110-based RFLP pattern simultaneously. Unique strains denoted those with the unparalleled MIRU genotype in the study collection. Socio-demographic and biomedical characteristics of host patients were compared between the clusters and unique groups through univariate and multivariate logistic regression analysis.
Based on the MIRU-IS6110 pattern, there were 52 isolates belonged to the "cluster" group and 171 as the "unique" group. Drug resistant M.TB strain isolated from patients at the age of 30 - 60 year had a higher probability of being clustered, comparing to those from patients below 30 years of age (30.9% vs. 11.9%; OR = 3.297; 95%CI: 1.169 - 9.297). Such finding were also seen in the isolates from patients with previous treatment history compared to newly diagnosed patients (32.9% vs. 18.4%; OR = 2.163, 95%CI: 1.144 - 4.090). The multi-drug resistant M.TB strain was found to have been more frequently clustered when comparing to the mono-drug resistant M.TB (47.2% vs. 15.5%; OR = 4.773; 95%CI: 2.316 - 9.837). The transmission pattern of drug resistant tuberculosis was presented mainly by the sporadic distribution in small group within rural villages.
Transmission of drug-resistant tuberculosis was seen in the population living in the Eastern rural areas of China, and causal contact within villages was considered as the main route of recent transmission. Patients at middle age and having previous tuberculosis treatment history might have increased the risk of transmission by patients with drug resistant tuberculosis.
从生物医学和社会人口学角度调查中国东部农村地区耐药结核分枝杆菌（M.TB）流行中近期传播的贡献及相关因素。
采用药物敏感性试验比例法确定，本研究纳入了223株耐药M.TB分离株及其宿主。这些耐药结核分枝杆菌分离株首先通过分枝杆菌插入重复单位（MIRU）进行基因分型，那些具有相同MIRU基因型的分离株再通过IS6110限制性片段多态性（RFLP）进一步分类。“簇”定义为两名患者的M.TB分离株同时具有相同的MIRU基因型和基于IS6110的RFLP模式。独特菌株指在研究样本中具有无与伦比的MIRU基因型的菌株。通过单因素和多因素逻辑回归分析比较簇组和独特组宿主患者的社会人口学和生物医学特征。
基于MIRU-IS6110模式，有52株分离株属于“簇”组，171株属于“独特”组。与30岁以下患者分离的耐药M.TB菌株相比，30 - 60岁患者分离的耐药M.TB菌株聚类的可能性更高（30.9%对11.9%；OR = 3.297；95%CI：1.169 - 9.297）。与新诊断患者相比，既往有治疗史患者分离的菌株也有类似情况（32.9%对18.4%；OR = 2.163，95%CI：1.144 - 4.090）。与单耐药M.TB相比，多耐药M.TB菌株聚类更频繁（47.2%对15.5%；OR = 4.773；95%CI：2.316 - 9.837）。耐药结核病的传播模式主要表现为农村村庄内小群体的散发性分布。
在中国东部农村地区的人群中发现了耐药结核病的传播，村庄内的因果接触被认为是近期传播的主要途径。中年且既往有结核病治疗史的患者可能增加了耐药结核病患者的传播风险。
