Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK.
J Antimicrob Chemother. 2010 Mar;65(3):446-8. doi: 10.1093/jac/dkp448. Epub 2009 Dec 24.
Between 1998 and 2000, 95.6% of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemias in the UK were due to two epidemic strains, namely EMRSA-15 or EMRSA-16 (60.2% and 35.4%, respectively). We sought to determine the proportions of these strains before and after the general decline in MRSA bacteraemia that began around 2004.
Consecutive MRSA isolates collected in 2001, 2003, 2005 and 2007 by the BSAC Bacteraemia Surveillance Programme were categorized to multilocus sequence typing (MLST) clonal complex and to SCCmec type by PCR. MICs were determined by the BSAC method. Data trends were tested for significance using a generalized linear regression model.
Collectively, EMRSA-15 and EMRSA-16 consistently accounted for approximately 95% of MRSA studied between 2001 and 2007, but the proportions of EMRSA-16 declined from 21.4% in 2001 to 9% in 2007 (P < 0.05), whilst the proportion of EMRSA-15 rose commensurately, accounting for 85% of MRSA in 2007. Ciprofloxacin and erythromycin resistance were common amongst both EMRSA-15 and EMRSA-16.
EMRSA-15 and EMRSA-16 remain the main MRSA strains in bacteraemia in the UK, but the proportion of EMRSA-16 declined from the late 1990 s, thus preceding the general decline in MRSA bacteraemias that began in the middle of the present decade.
1998 年至 2000 年间，英国耐甲氧西林金黄色葡萄球菌（MRSA）菌血症的 95.6%归因于两种流行株，即 EMRSA-15 或 EMRSA-16（分别为 60.2%和 35.4%）。我们试图确定 2004 年左右开始的 MRSA 菌血症普遍下降前后这些菌株的比例。
BSAC 菌血症监测计划于 2001 年、2003 年、2005 年和 2007 年连续收集的 MRSA 分离株通过多位点序列分型（MLST）克隆复合体和 SCCmec 型 PCR 进行分类。通过 BSAC 方法测定 MIC。使用广义线性回归模型测试数据趋势的显著性。
总的来说，EMRSA-15 和 EMRSA-16 在 2001 年至 2007 年期间一直占研究中 MRSA 的 95%左右，但 EMRSA-16 的比例从 2001 年的 21.4%下降到 2007 年的 9%（P<0.05），而 EMRSA-15 的比例相应上升，2007 年占 MRSA 的 85%。环丙沙星和红霉素耐药在 EMRSA-15 和 EMRSA-16 中均很常见。
EMRSA-15 和 EMRSA-16 仍然是英国菌血症中主要的 MRSA 菌株，但 EMRSA-16 的比例从 20 世纪 90 年代末开始下降，因此先于本世纪中叶开始的 MRSA 菌血症普遍下降。
