Background On January 7, 2019, we observed an outbreak of healthcare-associated infection (HAI) caused by Carbapenem-resistant Acinetobacter baumannii (CRAB) in the neurosurgical intensive care unit (NSICU). A follow-up epidemiological investigation was conducted, and an emergency response was initiated. We aimed to study the clonal transmission of CRAB and its possible source. Methods A matched case-control (1:2) study was performed to identify the possible predisposing factors. A multifaceted intervention was implemented to control the outbreak. We collected environmental samples from patients' rooms and living area of the staff. CRAB isolates were tested for genetic relatedness by Pulsed-Field Gel Electrophoresis (PFGE). Results Environmental sampling showed that a faucet aerator was contaminated with A. baumannii. Molecular typing revealed the only outbreak strain, which was isolated from tracheal aspirate cultures of the first case of community-acquired infection and 3 cases of HAI. In environmental samples, the outbreak strain was found only in the faucet aerator of the dining room. This CRAB outbreak was discovered in time, and further progress of this outbreak was prevented through a pre-set emergency response procedure. Conclusions The faucet aerator acted as a reservoir for bacteria in the outbreak, and contamination of the faucet aerator might have occurred from splashes originating from handwashing by the healthcare workers (HCWs). In high-risk areas, such as NSICU, the faucet aerators should not be used during an outbreak or they should be regularly cleaned and disinfected. The start-up criteria for the emergency response played a key role in controlling the CRAB outbreak, and its settings should be discussed more widely.

中文翻译：

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龙头曝气器可作为耐碳青霉烯的鲍曼不动杆菌的蓄水池：神经外科重症监护病房中与医疗保健相关的感染暴发。

背景技术2019年1月7日，我们在神经外科重症监护病房（NSICU）观察到由耐碳青霉烯类鲍曼不动杆菌（CRAB）引起的医疗保健相关感染（HAI）的暴发。进行了后续的流行病学调查，并启动了应急响应。我们旨在研究CRAB的克隆传播及其可能的来源。方法进行匹配的病例对照（1：2）研究，以确定可能的诱发因素。实施了多方面的干预措施来控制疫情。我们从患者房间和员工居住区域收集了环境样本。通过脉冲场凝胶电泳（PFGE）测试了CRAB分离物的遗传相关性。结果环境采样表明，水龙头曝气器被鲍曼不动杆菌污染。分子分型揭示了唯一的暴发菌株，该菌株是从第一例社区获得性感染和3例HAI的气管吸出物培养物中分离出来的。在环境样本中，仅在饭厅的龙头曝气机中发现了爆发菌株。及时发现了该CRAB爆发，并且通过预先设置的紧急响应程序阻止了该爆发的进一步进展。结论龙头曝气器在暴发中充当细菌的储存器，并且龙头曝气器的污染可能是由医护人员（HCW）洗手引起的飞溅引起的。在高风险地区，例如NSICU，在暴发期间不应使用龙头曝气器，或应定期清洁和消毒龙头曝气器。