一起皮肤炭疽疫情病原的实验室检测及毒力基因鉴定

Detection of Bacillusanthracisand identification of virulence genes directly from clinical material and beef in an anthrax outbreak

目的对2012年江苏省连云港市赣榆县一起皮肤炭疽疫情的病人临床标本及病牛肉标本进行快速分子诊断及毒力基因的鉴定。方法用Real-time PCR方法对病人的血、焦痂标本及病牛肉标本进行炭疽杆菌染色体编码的rpoB基因及质粒PXO1、PXO2上pag、capA基因的检测,并对质粒上4种毒力基因(cya,pag,lef,cap)进行扩增并测序。结果病人焦痂标本和病牛肉标本中均检测出rpoB基因和质粒PXO1、PXO2基因,4种毒力基因的测序结果证实扩增序列为炭疽杆菌质粒基因片段,病人标本与病牛肉标本的基因序列完全一致。结论实验室检测结果证实此次皮肤炭疽疫情是由当地村民宰杀携带炭疽杆菌强毒株的病牛引起。

Molecular diagnostics methods were used for detecting Bacillus anthraci and identifying virulence genes di- rectly from clinical material and infected beef in a cutaneous anthrax outbreak in Lianyungang City, Jiangsu Province, PR Chi- na, 2012. Blood and eschar samples were obtained from suspected cutaneous anthrax patients and the beef was collected from the sick cow. The chromosome gene （rpoB） and plasmid genes （pag, capA） of B. anthraci were detected directly from DNA of samples by real-time PCRI The virulence genes （cya, pag, lef and cap） of B. anthraci were identified by conventional PCR and genetiely analyzed by sequencing. The results showed that the identity of DNA from patients＂ eschar and beef were further confirmed positive to the genes rpoB, pag and capA of B. anthraci. The sequencing results confirmed that the amplified se- quences were virulence genes of B. anthraci. The sequences of each virulent gene from patients and beef were identical. The results revealed that this outbreak was caused by virulent strain of B. anthracis transmitted by contacts of the beef of the sick COW.