National MRSA Reference Laboratory, St. James’s Hospital, Dublin, Ireland.
J Clin Microbiol. 2012 Mar;50(3):841-7. doi: 10.1128/JCM.06354-11. Epub 2011 Dec 21.
Sequence type 22 (ST22) methicillin-resistant Staphylococcus aureus (MRSA) harboring staphylococcal cassette chromosome mec (SCCmec) IV (ST22-MRSA-IV) has predominated in Irish hospitals since the late 1990s. Six distinct clones of community-associated MRSA (CA-MRSA) have also been identified in Ireland. A new strain of CA-MRSA, ST772-MRSA-V, has recently emerged and become widespread in India and has spread into hospitals. In the present study, highly similar MRSA isolates were recovered from seven colonized neonates in a neonatal intensive care unit (NICU) in a maternity hospital in Ireland during 2010 and 2011, two colonized NICU staff, one of their colonized children, and a NICU environmental site. The isolates exhibited multiantibiotic resistance, spa type t657, and were assigned to ST772-MRSA-V by DNA microarray profiling. All isolates encoded resistance to macrolides [msr(A) and mpb(BM)] and aminoglycosides (aacA-aphD and aphA3) and harbored the Panton-Valentine leukocidin toxin genes (lukF-PV and lukS-PV), enterotoxin genes (sea, sec, sel, and egc), and one of the immune evasion complex genes (scn). One of the NICU staff colonized by ST772-MRSA-V was identified as the probable index case, based on recent travel to India. Seven additional hospital and CA-ST772-MRSA-V isolates recovered from skin and soft tissue infections in Ireland between 2009 and 2011 exhibiting highly similar phenotypic and genotypic characteristics to the NICU isolates were also identified. The clinical details of four of these patients revealed connections with India through ethnic background or travel. Our study indicates that hospital-acquired and CA-ST772-MRSA-V is currently emerging in Ireland and may have been imported from India on several occasions.
自 20 世纪 90 年代末以来，22 型序列（ST22）耐甲氧西林金黄色葡萄球菌（MRSA）携带葡萄球菌盒染色体 mec（SCCmec）IV（ST22-MRSA-IV）在爱尔兰医院中占据主导地位。在爱尔兰，也已经确定了六种不同的社区相关耐甲氧西林金黄色葡萄球菌（CA-MRSA）克隆。一种新的 CA-MRSA 菌株，ST772-MRSA-V，最近在印度出现并广泛传播，并已传播到医院。在本研究中，2010 年至 2011 年，在爱尔兰一家妇产医院的新生儿重症监护病房（NICU）中，从 7 名定植的新生儿中回收了高度相似的 MRSA 分离株，两名定植的 NICU 工作人员，他们的一名定植儿童，和一个 NICU 环境地点。这些分离株表现出多药耐药性，spa 型 t657，并通过 DNA 微阵列分析被分配到 ST772-MRSA-V。所有分离株均编码对大环内酯类[msr(A)和 mpb(BM)]和氨基糖苷类（aacA-aphD 和 aphA3）的耐药性，并携带杀白细胞素毒素基因（lukF-PV 和 lukS-PV）、肠毒素基因（sea、sec、sel 和 egc）和免疫逃避复合物基因（scn）之一。根据最近前往印度的旅行，一名被 ST772-MRSA-V 定植的 NICU 工作人员被确定为可能的索引病例。2009 年至 2011 年期间，从爱尔兰皮肤和软组织感染中回收的另外 7 株医院和 CA-ST772-MRSA-V 分离株，其表型和基因型特征与 NICU 分离株高度相似。这 4 名患者的临床细节表明，他们与印度之间存在着种族背景或旅行方面的联系。我们的研究表明，医院获得性和 CA-ST772-MRSA-V 目前正在爱尔兰出现，并且可能已经多次从印度进口。
