Centre for Infectious Diseases, University of Edinburgh College of Medicine and Veterinary Medicine, The Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
J Med Microbiol. 2011 Aug;60(Pt 8):1218-1224. doi: 10.1099/jmm.0.030288-0. Epub 2011 Apr 7.
Clostridium difficile is a common nosocomial pathogen transmitted mainly via its spores. These spores can remain viable on contaminated surfaces for several months and are resistant to most commonly used cleaning agents. Thus, effective decontamination of the environment is essential in preventing the transmission of C. difficile in health-care establishments. However, this emphasis on decontamination must also be extended to laboratories due to risk of exposure of staff to potentially virulent strains. Though few cases of laboratory-acquired infection have been reported, the threat of infection by C. difficile in the laboratory is real. Our aim was to test the efficacy of four disinfectants, Actichlor, MicroSol 3+, TriGene Advance and Virkon, and one laboratory decontaminant, Decon 90, against vegetative cells and spores of C. difficile. Five strains were selected for the study: the three most commonly encountered epidemic strains in Scotland, PCR ribotypes 106, 001 and 027, and control strains 630 and VPI 10463. MICs were determined by agar dilution and broth microdilution. All the agents tested inhibited the growth of vegetative cells of the selected strains at concentrations below the recommended working concentrations. Additionally, their effect on spores was determined by exposing the spores of these strains to different concentrations of the agents for different periods of time. For some of the agents, an exposure of 10 min was required for sporicidal activity. Further, only Actichlor was able to bring about a 3 log(10) reduction in spore numbers under clean and dirty conditions. It was also the only agent that decontaminated different hard, non-porous surfaces artificially contaminated with C. difficile spores. However, this too required an exposure time of more than 2 min and up to 10 min. In conclusion, only the chlorine-releasing agent Actichlor was found to be suitable for the elimination of C. difficile spores from the environment, making it the agent of choice for the decontamination of laboratory surfaces.
艰难梭菌是一种常见的医院病原体，主要通过其孢子传播。这些孢子在污染的表面上可以存活数月，并且对大多数常用的清洁剂具有抗性。因此，有效地对环境进行消毒对于预防艰难梭菌在医疗机构中的传播至关重要。然而，由于工作人员接触潜在毒力菌株的风险，这种对消毒的重视也必须扩展到实验室。虽然很少有实验室获得性感染的病例报告，但实验室中艰难梭菌感染的威胁是真实存在的。我们的目的是测试四种消毒剂（Actichlor、MicroSol 3+、TriGene Advance 和 Virkon）和一种实验室去污剂（Decon 90）对艰难梭菌的营养细胞和孢子的功效。选择了五个菌株进行研究：苏格兰最常见的三种流行菌株，PCR 核糖型 106、001 和 027，以及对照菌株 630 和 VPI 10463。通过琼脂稀释和肉汤微量稀释法测定 MIC。所有测试的试剂在低于推荐工作浓度的浓度下均能抑制所选菌株的营养细胞生长。此外，还通过将这些菌株的孢子暴露于不同浓度的试剂中不同的时间来确定它们对孢子的作用。对于一些试剂，需要 10 分钟的暴露才能实现杀菌活性。此外，只有 Actichlor 能够在清洁和污染条件下使孢子数量减少 3 个对数（10）。它也是唯一能够对人工污染有艰难梭菌孢子的不同硬、非多孔表面进行去污的试剂。然而，这也需要超过 2 分钟和长达 10 分钟的暴露时间。总之，只有含氯释放剂 Actichlor 被发现适合从环境中消除艰难梭菌孢子，使其成为实验室表面去污的首选试剂。
