This study aims to determine the prevalence of Staphylococcus aureus colonizing patients and ICU environment of a teaching hospital, the virulence and antimicrobial susceptibility profile of the isolates, and to evaluate the genetic relationship among them. A total of 536 swabs (134 of patients and 402 of ICU environment) were collected and analyzed to detect S. aureus. The antimicrobial susceptibility of the isolates was determined by disk diffusion test, and the detection of the mecA and virulence factors genes was performed by PCR, in addition to SCCmec typing. The genetic similarity of the isolates was determined by PFGE. Staphylococcus aureus was isolated in 12.7% of the swabs. The prevalence of colonization was 13.4% in patients and 12.4% in the environmental samples. The multidrug resistance was determined in 82.4% of the isolates. The prevalence of methicillin-resistant S. aureus was 20.6%, with 50.0% classified as SCCmec IV. The intermediate resistance to vancomycin was detected in 5.9% and 4.4% of the isolates obtained from patients and environment, respectively. Identical isolates obtained from different patients and sources were grouped into several clusters. The results showed dissemination of multidrug-resistant strains between patients and fomites and the persistence of MRSA and VISA isolates in the ICU environment.

中文翻译：

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耐甲氧西林和万古霉素金黄色葡萄球菌定植的患者和重症监护病房环境：毒力谱和遗传变异性。

这项研究旨在确定金黄色葡萄球菌定植患者的患病率和教学医院的ICU环境，分离株的毒力和抗菌药敏性，并评估它们之间的遗传关系。总共收集了536个拭子（134个患者和402个ICU环境），并进行分析以检测金黄色葡萄球菌。除SCCmec分型外，还通过圆盘扩散试验确定了分离物的抗药性，并通过PCR检测了mecA和毒力因子基因。分离物的遗传相似性通过PFGE确定。在12.7％的拭子中分离出金黄色葡萄球菌。患者中定植的患病率为13.4％，环境样品中定植的患病率为12.4％。在82.4％的分离物中确定了多药耐药性。耐甲氧西林的金黄色葡萄球菌的患病率为20.6％，其中50.0％归为SCCmec IV。从患者和环境中分离出的分离株分别对万古霉素具有中等耐药性，分别为5.9％和4.4％。从不同患者和来源获得的相同分离株被分为几类。结果表明，在患者和毒气分子之间传播了多药耐药菌株，以及ICU环境中MRSA和VISA分离株的持续存在。