Identification of Clostridium difficile Reservoirs in The Patient Environment and Efficacy of Aerial Hydrogen Peroxide Decontamination

Abstract

OBJECTIVETo identify, using a novel enhanced method of recovery, environmental sites where spores of Clostridium difficile persist despite cleaning and hydrogen peroxide aerial decontamination.DESIGNCohort study.SETTINGTertiary referral center teaching hospital.METHODSIn total, 16 sites representing high-frequency contact or difficult-to-clean surfaces in a single-isolation room or bed area in patient bed bays were sampled before and after terminal or hydrogen peroxide disinfection using a sponge swab. In some rooms, individual sites were not present (eg, there were no en-suite rooms in the ICU). Swab contents were homogenized, concentrated by membrane-filtration, and plated onto selective media. Results of C. difficile sampling were used to focus cleaning.RESULTSOver 1 year, 2,529 sites from 146 rooms and 44 bays were sampled. Clostridium difficile was found on 131 of 572 surfaces (22.9%) before terminal cleaning, on 105 of 959 surfaces (10.6%) after terminal cleaning, and on 43 of 967 surfaces (4.4%) after hydrogen peroxide disinfection. Clostridium difficile persisted most frequently on floor corners (97 of 334; 29.0%) after disinfection. Between the first and third quarters, we observed a significant decrease in the number of positive sites (25 of 390 vs 6 of 256). However, no similar change in the number of isolates before terminal cleaning was observed.CONCLUSIONPersistence of C. difficile in the clinical environment was widespread. Although feedback of results did not improve the efficacy of manual disinfection, numbers of C. difficile following hydrogen peroxide gradually declined.Infect Control Hosp Epidemiol 2017;38:1487–1492