Whole genome SNP typing to investigate methicillin-resistant Staphylococcus aureus carriage in a health-care provider as the source of multiple surgical site infections.
Whole genome SNP typing to investigate methicillin-resistant Staphylococcus aureus carriage in a health-care provider as the source of multiple surgical site infections.
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DOI：
10.1186/s41065-016-0017-x
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发表时间：
2016
期刊：
影响因子：
2.7
通讯作者：
Engelthaler DM
中科院分区：
文献类型：
--
作者：
Roe CC;Horn KS;Driebe EM;Bowers J;Terriquez JA;Keim P;Engelthaler DM
预防感染的医院传播是医疗环境中的核心责任，而准确识别传播事件是第一个挑战。基于全基因组测序的系统发育分析提供了一种高分辨率方法，可以准确地将分离株相互关联起来，从而可以精确识别或排除几乎所有病例的传播事件和来源。我们对 24 个耐甲氧西林金黄色葡萄球菌 (MRSA) 基因组进行了测序，以回顾性调查一年内发生的三个手术部位感染 (SSI) 的可疑点源。据信，传播源是一名被 MRSA 定植的手术团队成员，他参与了 SSI 病例之前的所有手术，随后被去定植。使用全基因组单核苷酸多态性（SNP）数据确定分离株之间的遗传相关性。全基因组 SNP 分型 (WGST) 揭示了手术团队成员的分离株与最接近的 SSI 分离株之间存在 283 个信息丰富的 SNP。第二个分离株有 286 个，第三个分离株有数千个不同的 SNP，表明手术团队成员的鼻腔压力不是 SSI 的来源。考虑到金黄色葡萄球菌的突变率，在过去 16 年里，没有任何 SSI 分离株具有共同的祖先，这进一步排除了这些感染的任何共同点源。如果在疑似传播时而不是回顾性地进行 WGST，则可以避免用于点源感染控制的去殖民化程序和资源。全基因组序列分析是排除涉及传播事件和医院暴发的分离株的理想方法，将该方法与流行病学数据相结合可以确定是否发生了传播事件。这些方法有望更适当地引导感染控制资源。本文的在线版本 (doi:10.1186/s41065-016-0017-x) 包含补充材料，可供授权用户使用。
Prevention of nosocomial transmission of infections is a central responsibility in the healthcare environment, and accurate identification of transmission events presents the first challenge. Phylogenetic analysis based on whole genome sequencing provides a high-resolution approach for accurately relating isolates to one another, allowing precise identification or exclusion of transmission events and sources for nearly all cases. We sequenced 24 methicillin-resistant Staphylococcus aureus (MRSA) genomes to retrospectively investigate a suspected point source of three surgical site infections (SSIs) that occurred over a one-year period. The source of transmission was believed to be a surgical team member colonized with MRSA, involved in all surgeries preceding the SSI cases, who was subsequently decolonized. Genetic relatedness among isolates was determined using whole genome single nucleotide polymorphism (SNP) data. Whole genome SNP typing (WGST) revealed 283 informative SNPs between the surgical team member’s isolate and the closest SSI isolate. The second isolate was 286 and the third was thousands of SNPs different, indicating the nasal carriage strain from the surgical team member was not the source of the SSIs. Given the mutation rates estimated for S. aureus, none of the SSI isolates share a common ancestor within the past 16 years, further discounting any common point source for these infections. The decolonization procedures and resources spent on the point source infection control could have been prevented if WGST was performed at the time of the suspected transmission, instead of retrospectively. Whole genome sequence analysis is an ideal method to exclude isolates involved in transmission events and nosocomial outbreaks, and coupling this method with epidemiological data can determine if a transmission event occurred. These methods promise to direct infection control resources more appropriately. The online version of this article (doi:10.1186/s41065-016-0017-x) contains supplementary material, which is available to authorized users.