Tsang R S, Deeks S L, Wong K, Marchand-Austin A, Jamieson F B
National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB.
Public Health Ontario, Toronto, ON.
Can Commun Dis Rep. 2016 Dec 1;42(12):263-266. doi: 10.14745/ccdr.v42i12a06.
In Ontario, serogroup W (MenW) accounts for a small percentage of all invasive meningococcal disease (IMD) and between 2010 and 2014, only zero to three confirmed cases occurred per year. However, between August 2015 and June 2016, six culture confirmed MenW IMD cases were reported in Ontario.
All MenW IMD cases in Ontario between January 1, 2009 and June 30, 2016 were reviewed and the strains involved were characterized.
MenW cases were identified in the Integrated Public Health Information System byf Public Health Ontario. MenW isolates were characterized at the National Microbiology Laboratory.
Of the thirteen MenW IMD cases, six were due to isolates typed as sequence type (ST)-22 clonal complex (cc), six were of ST-11 cc, and one ST-167 cc. Most (83%) MenW cases due to the ST-22 cc occurred prior to 2012 while all six MenW cases due to ST-11 cc happened since May 2014. The six MenW ST-11 isolates appeared to be clonal.
It appears that a genetic shift in the invasive MenW isolates has occurred in Ontario in 2014 with the ST-11 clone replacing the traditional ST-22 clone.
在安大略省，W群脑膜炎球菌（MenW）在所有侵袭性脑膜炎球菌病（IMD）中所占比例较小，在2010年至2014年期间，每年仅出现0至3例确诊病例。然而，在2015年8月至2016年6月期间，安大略省报告了6例经培养确诊的MenW IMD病例。
对2009年1月1日至2016年6月30日安大略省所有MenW IMD病例进行回顾，并对所涉及的菌株进行特征分析。
安大略省公共卫生部门在综合公共卫生信息系统中识别MenW病例。MenW分离株在国家微生物实验室进行特征分析。
在13例MenW IMD病例中，6例是由分型为序列型（ST）-22克隆复合体（cc）的分离株引起的，6例是ST-11 cc，1例是ST-167 cc。大多数（83%）由ST-22 cc引起的MenW病例发生在2012年之前，而所有6例由ST-11 cc引起的MenW病例均发生在2014年5月之后。6株MenW ST-11分离株似乎是克隆性的。
2014年安大略省侵袭性MenW分离株似乎发生了基因转变，ST-11克隆取代了传统的ST-22克隆。
