Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO; Division of Emergency Medicine, Washington University School of Medicine, St. Louis, MO.
Division of Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, St. Louis, MO.
Ann Emerg Med. 2019 Jul;74(1):50-55. doi: 10.1016/j.annemergmed.2018.12.014. Epub 2019 Feb 4.
Methicillin-resistant Staphylococcus aureus (MRSA) transmission dynamics in the emergency department (ED) are not well defined; environmental surfaces may serve as reservoirs for transmission. This study investigates the effect of patients with a history of MRSA colonization or infection on subsequent MRSA contamination of the ED environment.
Adult ED patients with evidence of an MRSA-positive surveillance result or clinical microbiologic culture in the year preceding their current ED visit were enrolled. Cultures from 5 anatomic sites were obtained to detect active MRSA colonization. After patients' discharge and before environmental disinfection, up to 16 prespecified surfaces in their ED rooms were cultured. Strain typing was performed by repetitive-sequence polymerase chain reaction on all recovered MRSA isolates to determine concordance with the corresponding patient strain.
Of 42 patients enrolled, 25 (60%) remained colonized with MRSA. Nineteen of the 25 ED rooms (76%) occupied by MRSA-colonized patients contained greater than or equal to 1 MRSA-contaminated environmental surface on patient discharge. Surfaces were more likely to be contaminated when rooms were occupied by patients colonized with MRSA at 1 body site (odds ratio 11.7; 95% confidence interval 1.5 to 91.5) and greater than or equal to 2 body sites (odds ratio 16.3; 95% confidence interval 3.1 to 86.8) compared with noncolonized patients. In 16 of the 19 ED rooms (84%) where MRSA was recovered, all environmental strains were concordant with the corresponding patient strain.
Contamination of the ED environment with MRSA from actively colonized patients is common. Improved environmental surface disinfection may help reduce transmission of MRSA to ED health care professionals and patients during emergency care.
耐甲氧西林金黄色葡萄球菌（MRSA）在急诊科（ED）的传播动力学尚不清楚；环境表面可能是传播的储库。本研究调查了具有 MRSA 定植或感染史的患者对 ED 环境随后发生 MRSA 污染的影响。
入选前一年 ED 就诊时出现 MRSA 阳性监测结果或临床微生物培养阳性的成年 ED 患者。采集 5 个解剖部位的标本，以检测活跃的 MRSA 定植。在患者出院后、环境消毒前，对其 ED 房间内最多 16 个预定表面进行培养。对所有回收的 MRSA 分离株进行重复序列聚合酶链反应（PCR）进行菌株分型，以确定与相应患者株的一致性。
42 名入组患者中，25 名（60%）仍携带 MRSA 定植。19 间（76%）由 MRSA 定植患者居住的 ED 房间在患者出院时含有大于或等于 1 个 MRSA 污染的环境表面。当房间由定植于 1 个部位（比值比 11.7；95%置信区间 1.5 至 91.5）和定植于大于或等于 2 个部位（比值比 16.3；95%置信区间 3.1 至 86.8）的患者时，表面更有可能被污染与未定植的患者相比。在 19 间（84%）回收 MRSA 的 ED 房间中，所有环境菌株与相应的患者株一致。
来自活跃定植患者的 ED 环境中 MRSA 的污染很常见。改善环境表面消毒可能有助于减少 ED 医护人员和患者在急救期间发生 MRSA 传播。
