Panagea S, Winstanley C, Walshaw M J, Ledson M J, Hart C A
Department of Medical Microbiology and Genito-urinary Medicine, University of Liverpool, Liverpool L69 3GA, UK.
J Hosp Infect. 2005 Feb;59(2):102-7. doi: 10.1016/j.jhin.2004.09.018.
We conducted an environmental survey in the Liverpool adult cystic fibrosis (CF) centre in order to determine the extent of environmental contamination with an epidemic strain of Pseudomonas aeruginosa that colonizes most CF patients in Liverpool, and to identify possible reservoirs and routes of cross-infection. In addition, we studied the survival of this strain on dry surfaces, compared with that of other CF P. aeruginosa strains, to explore factors that might contribute to its high transmissibility. Samples were collected from staff, patients and the environment (drains, bath tubs, showers, dry surfaces, respiratory equipment and air) in the inpatient ward and outpatient clinic. P. aeruginosa strains were tested using a new polymerase chain reaction amplification assay specific for the Liverpool epidemic strain (LES). LES was isolated from patients' hands, clothes and bed linen. Environmental contamination with LES was only detected in close proximity to colonized patients (external surfaces of their respiratory equipment, and spirometry machine tubing and chair) and was short-lived. No persistent environmental reservoirs were found. LES was detected in the majority of air samples from inside patients' rooms, the ward corridor and the outpatient clinic. Survival of LES on dry surfaces was significantly longer than that for some other strains tested, but not compared with other strains shown not to be transmissible. Improved environmental survival on its own, therefore, cannot explain the high transmissibility of this epidemic strain. Our study suggests that airborne dissemination plays a significant role in patient-to-patient spread of LES, and confirms the need to segregate those patients colonized by epidemic P. aeruginosa strains from all other CF patients.
我们在利物浦成人囊性纤维化（CF）中心进行了一项环境调查，以确定被一株流行的铜绿假单胞菌污染的环境范围，该菌株定植于利物浦的大多数CF患者体内，并确定可能的储存宿主和交叉感染途径。此外，我们研究了该菌株在干燥表面上的存活情况，并与其他CF铜绿假单胞菌菌株进行比较，以探索可能导致其高传播性的因素。样本取自住院病房和门诊诊所的工作人员、患者以及环境（排水管道、浴缸、淋浴间、干燥表面、呼吸设备和空气）。使用一种针对利物浦流行菌株（LES）的新型聚合酶链反应扩增检测方法对铜绿假单胞菌菌株进行检测。LES从患者的手部、衣物和床单上分离得到。仅在定植患者附近（其呼吸设备的外表面、肺活量计的管道和椅子）检测到LES对环境的污染，且污染持续时间较短。未发现持久性的环境储存宿主。在患者病房内、病房走廊和门诊诊所的大多数空气样本中都检测到了LES。LES在干燥表面上的存活时间明显长于其他一些受试菌株，但与其他显示无传播性的菌株相比则不然。因此，仅环境存活能力的提高并不能解释该流行菌株的高传播性。我们的研究表明，空气传播在LES的患者间传播中起重要作用，并证实有必要将感染流行铜绿假单胞菌菌株的患者与所有其他CF患者隔离开来。
