Leong Kelvin W C, Kalukottege Ranmini, Cooley Louise A, Anderson Tara L, Wells Anne, Langford Emma, O'Toole Ronan F
Department of Pharmacy and Biomedical Sciences, School of Molecular Sciences, College of Science, Health and Engineering, La Trobe University, Albury-Wodonga, VIC, Australia.
Department of Microbiology, Launceston General Hospital, Launceston, TAS, Australia.
Front Microbiol. 2020 Jan 15;10:2940. doi: 10.3389/fmicb.2019.02940. eCollection 2019.
From 2015 onwards, the number of vancomycin-resistant (VREfm) isolates increased in Tasmania. Previously, we examined the transmission of VREfm at the Royal Hobart Hospital (RHH). In this study, we performed a state-wide analysis of VREfm from Tasmania's four public acute hospitals. Whole-genome analysis was performed on 331 isolates collected from screening and clinical specimens of VREfm. multi-locus sequence typing (MLST) was used to determine the relative abundance of broad sequence types (ST) across the state. Core genome MLST (cgMLST) was then applied to identify potential clades within the ST groupings followed by single-nucleotide polymorphic (SNP) analysis. This work revealed that differences in VREfm profiles are evident between the state's two largest hospitals with the dominant types being ST80 at the RHH and ST1421 at Launceston General Hospital (LGH). A higher number of VREfm cases were recorded at LGH ( = 54 clinical, = 122 colonization) compared to the RHH ( = 14 clinical, = 67 colonization) during the same time period, 2014-2016. Eleven of the clinical isolates from LGH were and belonged to ST1421 ( = 8), ST1489 ( = 1), ST233 ( = 1), and ST80 ( = 1) whereas none of the clinical isolates from the RHH were . For the recently described ST1421, cgMLST established the presence of individual clusters within this sequence type that were common to more than one hospital and that included isolates with a low amount of SNP variance (≤16 SNPs). A spatio-temporal analysis revealed that VREfm ST1421 was first detected at the RHH in 2014 and an isolate belonging to the same cgMLST cluster was later collected at LGH in 2016. Inclusion of isolates from two smaller hospitals, the North West Regional Hospital (NRH) and the Mersey Community Hospital (MCH) found that ST1421 was present in both of these institutions in 2017. These findings illustrate the spread of a recently described sequence type of VREfm, ST1421, to multiple hospitals in an Australian state within a relatively short time span.
自2015年起，塔斯马尼亚州耐万古霉素肠球菌（VREfm）分离株数量增加。此前，我们研究了皇家霍巴特医院（RHH）的VREfm传播情况。在本研究中，我们对塔斯马尼亚州四家公立急症医院的VREfm进行了全州范围的分析。对从VREfm筛查和临床标本中收集的331株分离株进行了全基因组分析。采用多位点序列分型（MLST）来确定全州范围内广泛序列类型（ST）的相对丰度。然后应用核心基因组MLST（cgMLST）来识别ST分组内的潜在进化枝，随后进行单核苷酸多态性（SNP）分析。这项工作表明，该州两家最大医院的VREfm谱存在差异，RHH的主要类型是ST80，朗塞斯顿总医院（LGH）的主要类型是ST1421。在2014 - 2016年同一时期，LGH记录的VREfm病例数（临床病例 = 54例，定植病例 = 122例）高于RHH（临床病例 = 14例，定植病例 = 67例）。LGH的11株临床分离株为[此处原文缺失相关描述]，属于ST1421（8株）、ST1489（1株）、ST233（1株）和ST80（1株），而RHH的临床分离株均无[此处原文缺失相关描述]。对于最近描述的ST1421，cgMLST确定了该序列类型内存在个体簇，这些簇在多家医院中常见，并且包括SNP变异量低（≤16个SNP）的分离株。时空分析显示，VREfm ST1421于2014年首次在RHH被检测到，后来在2016年LGH收集到了属于同一cgMLST簇的分离株。纳入西北区医院（NRH）和默西社区医院（MCH）这两家较小医院的分离株后发现，2017年这两家机构均存在ST1421。这些发现说明了一种最近描述的VREfm序列类型ST1421在相对较短的时间内传播到了澳大利亚一个州的多家医院。
