The present paper aims to determine the prevalence of Beijing strains of Mycobacterium tuberculosis isolated from visa applicants in Shanghai Port ,to define the probability of drug resistance and to evaluate the underlying risks of dissemination of Mycobacterium tuberculosis and tuberculosis burden for Chinese tuberculosis surveillance system .From January 2009 to May 2013 ,a total of 193 visa applicants who received medical examinations in Shanghai Port were suspected of infectious tuberculosis by detected abnormalities in the chest radiology . Smear and culture examination from 3 consecutive early morning sputum specimens collected from them were performed .Isolated Mycobacterium tuberculosis complex strains were subjected for genotyping using deletion-targeted multiplex polymerase chain reaction (DTM-PCR ) . Fifty of them were positive for Mycobacterium tuberculosis complex . Forty isolates were genotyped by DTM-PCR ,23 of the isolates (57 .5% ) belonged to Beijing genotype .The ratio was significantly lower than that in the local people going abroad (37/41 ,90 .2% ) .In all imported cases with Beijing genotype ,5 were from South-East Asia Region and 16 were from Western Pacific Region .Of 23 Beijing strains ,7 (30 .4% ) were resistant to at least one first-line anti-tuberculosis drug ,which was similar to the drug resistance rate (34 .1% ) in the local people going abroad . No multidrug-resistant Beijing strain was found . The drug resistance rate to pyrazinamide was much higher in visa applicants (16 .7% ) than that in the local people going abroad (2 .4% ) .%本研究旨在了解上海口岸输入性传染性肺结核病患者中结核分枝杆菌北京型特征及其对一线抗结核药物的耐药情况，从而正确评估输入性结核病给上海地区带来的公共卫生危害，同时为地区传染性结核病防治策略的制定提供依据。针对2009年1月～2013年5月上海口岸入境体检人员中胸部影像学诊断疑似活动性肺结核病的人群，采集其连续3 d的晨痰分离培养结核分枝杆菌，用MGIT960培养法分析其对抗结核药物（链霉素、异烟肼、利福平、乙胺丁醇、吡嗪酰胺）的耐药情况，用目标缺失多重聚合酶链反应（DTM-PCR ）进行结核分枝杆菌北京型分子分型，同时采集其人口学资料。期间共监测到入境外籍疑似活动性肺结核病者193例，其中50例痰液中分离培养到结核分枝杆菌，菌培阳率为25．9％，与我国结核病普查工作中活动性肺结核病菌培阳率（25．9％）相同。分离培养并成功传代、分型的40株结核分枝杆菌中，北京型占57．5％（23／40），显著低于同期上海口岸出境人群中的90．2％（37／41）。输入性结核分枝杆菌北京型主要来自东南亚地区（71．4％，5／7）和西太平洋地区（57．1％，16／28）。一线5种抗结核药物的耐药性检测结果显示，输入性结核分枝杆菌北京型的总耐药率为30．4％（7／23），接近上海口岸出境人群的34．1％。输入性耐多药菌株占2．4％（1／42），分子分型结果显示为非北京型。输入性传染性肺结核病对吡嗪酰胺的耐药率为16．7％，显著高于上海口岸出境人群的2．4％。结果提示，上海口岸输入性肺结核病患者中结核分枝杆菌北京型所占比例显著低于同期出境人群，未发现与性别和年龄相关，未发现输入性结核分枝杆菌北京型对抗结核药物耐药性的显著变化。输入性耐药性结核病带来的公共卫生危害不容忽视，在直接督导下的短程化疗（DOTS）方案中需考虑其高吡嗪酰胺耐药特征。在口岸公共卫生安全风险评估中，需重视输入性结核分枝杆菌北京型与本地流行株的差异。
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