Sporicidal activity of two disinfectants against Clostridium difficile spores

University Hospital Birmingham, NHS Trust, Birmingham.
British journal of nursing (Mark Allen Publishing) 03/2008; 17(5):316-20. DOI: 10.12968/bjon.2008.17.5.28827
Source: PubMed


The sporicidal activity of an odour-free peracetic acid-based disinfectant (Wofasteril) and a widely-used dichloroisocyanurate preparation (Chlor-clean) was assessed against spores of the hyper-virulent strain of Clostridium difficile (ribotype 027), in the presence and absence of organic matter. In environmentally clean conditions, dichloroisocyanurate achieved a >3 log10 reduction in 3 minutes, but a minimum contact time of 9 minutes was required to reduce the viable spore load to below detection levels. Peracetic acid achieved a >3 log10 reduction in 30 minutes and was overall significantly less effective (P<0.05). However, in the presence of organic matter - which reflects the true clinical environment - there was no significant difference between the sporicidal activity of dichloroisocyanurate and peracetic acid over a 60-minute period (P=0.188). Given the greater occupational health hazards generally associated with chlorine-releasing agents, odour-free peracetic acid-based disinfectants may offer a suitable alternative for environmental disinfection.

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    • "Contamination of the clinical environment with spores of C. difficile is a key factor associated with the spread of CDI. Furthermore, patients with CDI excrete in excess 100 C. difficile spores and cells per gram of faeces (Wilcox 2003) and sporicidal agents, including bleach and peracetic acid, are required to eliminate these spores from the environment (Wheeldon et al. 2008b). Clostridium difficile infection occurs in susceptible patients following ingestion of spores from the environment, after which, the irreversible process of spore germination occurs in the small intestine giving rise to the metabolically active vegetative forms of C. difficile which produce the exotoxins associated with disease in the large intestine (Poutanen and Simor 2004; Moir 2006). "
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