Department of Clinical Microbiology, Health Sciences Centre/Diagnostic Services of Manitoba, Winnipeg, Manitoba R3A 1R9, Canada.
Diagn Microbiol Infect Dis. 2011 Mar;69(3):320-5. doi: 10.1016/j.diagmicrobio.2010.10.028.
This study assessed the demographics, antimicrobial susceptibility, and molecular epidemiology of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and health care-associated MRSA (HA-MRSA) in Canadian hospitals between 2007 and 2009. Among 3589 S. aureus, 889 (24.8%) were MRSA; 224 (25.2%) were CA-MRSA genotypes and 644 (72.4%) were HA-MRSA genotypes. The prevalence of CA-MRSA genotypes increased from 19.5% in 2007 to 31.9% in 2009 (P < .001). CMRSA10/USA300 (73.7%) was the predominant CA-MRSA epidemic type; the most common HA-MRSA epidemic type was CMRSA2/USA100/800 (83.5%). CA-MRSA genotypes carried SCCmec type IVa (98.2%) and were largely agr type I (73.2%). Most HA-MRSA genotypes were SCCmec type II (81.2%) and agr type II (83.4%). Panton-Valentine leukocidin was detected in 201/224 (89.7%) CA-MRSA genotypes and 3/644 (0.5%) HA-MRSA genotypes. An increase in vancomycin minimum inhibitory concentration (MIC) was observed in HA-MRSA genotypes overall, with 1.3% (4/305) of strains in 2007 and 4.6% (7/152) in 2009 exhibiting vancomycin MICs of 2 μg/mL. No MRSA resistance occurred with linezolid, daptomycin, or tigecycline. In conclusion, CA-MRSA genotypes represented 25.2% of all MRSA and continue to increase in prevalence in Canadian hospitals.
这项研究评估了 2007 年至 2009 年加拿大医院中社区获得性耐甲氧西林金黄色葡萄球菌 (CA-MRSA) 和 与医疗保健相关的耐甲氧西林金黄色葡萄球菌 (HA-MRSA) 的人口统计学、抗菌药物敏感性和分子流行病学情况。在 3589 株金黄色葡萄球菌中，889 株（24.8%）为耐甲氧西林金黄色葡萄球菌；224 株（25.2%）为 CA-MRSA 基因型，644 株（72.4%）为 HA-MRSA 基因型。CA-MRSA 基因型的流行率从 2007 年的 19.5%增加到 2009 年的 31.9%（P<.001）。CMRSA10/USA300（73.7%）是主要的 CA-MRSA 流行型；最常见的 HA-MRSA 流行型是 CMRSA2/USA100/800（83.5%）。CA-MRSA 基因型携带 SCCmec 类型 IVa（98.2%），并且主要是 agr 类型 I（73.2%）。大多数 HA-MRSA 基因型为 SCCmec 类型 II（81.2%）和 agr 类型 II（83.4%）。在 224 株 CA-MRSA 基因型中有 201 株（89.7%）和 644 株 HA-MRSA 基因型中的 3 株（0.5%）检测到了杀白细胞素。总体上，HA-MRSA 基因型的万古霉素最小抑菌浓度（MIC）增加，2007 年有 1.3%（4/305）的菌株和 2009 年有 4.6%（7/152）的菌株的万古霉素 MIC 为 2μg/ml。利奈唑胺、达托霉素或替加环素未出现 MRSA 耐药。总之，CA-MRSA 基因型占所有 MRSA 的 25.2%，并且在加拿大医院中的流行率持续增加。
