Liu Yudong, Wang Hui, Du Na, Shen Enhua, Chen Hongbin, Niu Junqi, Ye Huifen, Chen Minjun
Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing.
Antimicrob Agents Chemother. 2009 Feb;53(2):512-8. doi: 10.1128/AAC.00804-08. Epub 2008 Nov 24.
Methicillin (meticillin)-resistant Staphylococcus aureus (MRSA) is a serious problem worldwide. To investigate the molecular epidemiology of MRSA isolates in China, a total of 702 MRSA isolates collected from 18 teaching hospitals in 14 cities between 2005 and 2006 were characterized by antibiogram analysis, pulsed-field gel electrophoresis (PFGE), staphylococcal cassette chromosome mec (SCCmec) typing, and spa typing; and 102 isolates were selected for multilocus sequence typing (MLST). Overall, SCCmec type III was the most popular type and was found in 541 isolates (77.1%), followed by SCCmec type II (109/702; 15.5%). Twenty-four PFGE types were obtained among 395 isolates collected in 2005, and 18 spa types were obtained among 702 isolates. spa type t030, which corresponded to PFEG types A to E, constituted 52.0% (365/702) of all isolates, and isolates of this type were present in all 14 cities; spa type t037, which corresponded to PFGE types F and G, accounted for 25.5% (179/702) of all isolates, and isolates of this type were identified in 12 cities. The two spa genotypes belonged to sequence type 239 (ST239) and carried SCCmec type III. spa type t002, which included isolates of PFGE types L to T, made up 16.0% (112/702) of the isolates that belonged to ST5 and SCCmec type II, and isolates of this type were distributed in 12 cities. The distribution of spa types varied among the regions. spa type t002 was the most common in Dalian (53.4%) and Shenyang (44.4%); spa type t037 was predominant in Shanghai (74.8%), whereas spa type t030 was the most common in the other cities. Two isolates from Guangzhou that harbored SCCmec type IVa with ST59 and ST88 were identified as community-associated MRSA. The prevalence of the Panton-Valentine leukocidin gene was 2.3%. The data documented two major epidemic MRSA clones, ST239-MRSA-SCCmec type III and ST5-MRSA-SCCmec type II, with unique geographic distributions across China.
耐甲氧西林金黄色葡萄球菌（MRSA）是一个全球性的严重问题。为了调查中国MRSA分离株的分子流行病学，对2005年至2006年间从14个城市的18家教学医院收集的702株MRSA分离株进行了药敏分析、脉冲场凝胶电泳（PFGE）、葡萄球菌盒式染色体mec（SCCmec）分型和spa分型；并选择102株分离株进行多位点序列分型（MLST）。总体而言，SCCmecⅢ型是最常见的类型，在541株分离株中发现（77.1%），其次是SCCmecⅡ型（109/702；15.5%）。2005年收集的395株分离株中获得了24种PFGE型，702株分离株中获得了18种spa型。与PFEG A至E型相对应的spa t030型占所有分离株的52.0%（365/702），该类型的分离株在所有14个城市均有出现；与PFGE F和G型相对应的spa t037型占所有分离株的25.5%（179/702），该类型的分离株在12个城市被鉴定到。这两种spa基因型属于序列型239（ST239），携带SCCmecⅢ型。包括PFGE L至T型分离株的spa t002型占属于ST5和SCCmecⅡ型分离株的16.0%（112/702），该类型的分离株分布在12个城市。spa型的分布在不同地区有所不同。spa t002型在大连（53.4%）和沈阳（44.4%）最为常见；spa t037型在上海占主导地位（74.8%），而spa t030型在其他城市最为常见。从广州分离出的两株携带SCCmecⅣa型及ST59和ST88的菌株被鉴定为社区相关MRSA。杀白细胞素基因的流行率为2.3%。数据记录了两个主要的流行MRSA克隆，即ST239-MRSA-SCCmecⅢ型和ST5-MRSA-SCCmecⅡ型，在中国具有独特的地理分布。
