Ye Changyun, Zhu Xiaoping, Jing Huaiqi, Du Huamao, Segura Mariela, Zheng Han, Kan Biao, Wang Lili, Bai Xuemei, Zhou Yongyun, Cui Zhigang, Zhang Shouying, Jin Dong, Sun Na, Luo Xia, Zhang Ji, Gong Zhaolong, Wang Xin, Wang Lei, Sun Hui, Li Zhenjun, Sun Qiangzheng, Liu Honglu, Dong Boqing, Ke Changwen, Yuan Hui, Wang Hua, Tian Kecheng, Wang Yu, Gottschalk Marcelo, Xu Jianguo
State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Changping, Beijing 102206, People's Republic of China.
Emerg Infect Dis. 2006 Aug;12(8):1203-8. doi: 10.3201/eid1708.060232.
An outbreak of Streptococcus suis serotype 2 emerged in the summer of 2005 in Sichuan Province, and sporadic infections occurred in 4 additional provinces of China. In total, 99 S. suis strains were isolated and analyzed in this study: 88 isolates from human patients and 11 from diseased pigs. We defined 98 of 99 isolates as pulse type I by using pulsed-field gel electrophoresis analysis of SmaI-digested chromosomal DNA. Furthermore, multilocus sequence typing classified 97 of 98 members of the pulse type I in the same sequence type (ST), ST-7. Isolates of ST-7 were more toxic to peripheral blood mononuclear cells than ST-1 strains. S. suis ST-7, the causative agent, was a single-locus variant of ST-1 with increased virulence. These findings strongly suggest that ST-7 is an emerging, highly virulent S. suis clone that caused the largest S. suis outbreak ever described.
2005年夏季，四川省出现了2型猪链球菌疫情，中国另外4个省份也出现了散发病例。本研究共分离并分析了99株猪链球菌：88株分离自人类患者，11株分离自患病猪。通过对经SmaI酶切的染色体DNA进行脉冲场凝胶电泳分析，我们将99株分离株中的98株定义为脉冲型I。此外，多位点序列分型将脉冲型I的98个成员中的97个归为同一序列型（ST），即ST-7。ST-7分离株对外周血单核细胞的毒性比ST-1菌株更强。猪链球菌ST-7作为病原体，是ST-1的单基因座变体，毒力增强。这些发现有力地表明，ST-7是一种新出现的、高毒力的猪链球菌克隆株，它引发了有史以来描述的最大规模的猪链球菌疫情。
