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Summary Background The increasing prevalence of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in the healthcare setting and in the community despite established infection control guidelines indicates that these microorganisms may possess survival strategies that allow them to persist in the environment. Aims To determine the extent and variation in endemic ESBL-carrying species in different ward environments, and to investigate the potential for cephalosporin resistance to be transferred from environmental isolates to human pathogens. Methods Conventional microbiological methods were used to sample 1436 environmental surfaces for ESBL-producing bacteria. Transconjugation assays (broth mating experiments) were performed using environmental ESBL-producing isolates as donors and streptomycin-resistant Escherichia coli (NCTC 50237) as the recipient. Findings The prevalence of ESBL-producing bacteria on surfaces in a non-outbreak setting was low (45/1436; 3.1%). The sites most likely to be contaminated were the drains of handwash basins (28/105; 26.7%) and floors (14/160; 8.8%). Fifty-nine ESBL-carrying organisms were isolated. Of these, Klebsiella spp. (33.9%), Enterobacter spp. (20.3%), Pantoea spp. (15.3%) and Citrobacter spp. (13.6%) were the most common isolates. ESBL determinants were transferred successfully from three representative environmental isolates ( Pantoea calida, Klebsiella oxytoca, Raoultella ornithinolytica ) to the human pathogen E. coli . Conclusion ESBL-producing Gram-negative isolates were recovered from the hospital environment in the absence of any ESBL infection on the wards. The drains of handwash basins should be considered potential long-term reservoirs of multi-drug-resistant bacteria and drug resistance genes. These genes can reside in various genera of hardy environmental organisms and be a potential source of ESBL for more common human pathogens.

Summary Background Hydrogen peroxide vapour (HPV) disinfection systems are being used to reduce patients' exposure to hospital pathogens in the environment. HPV whole-room aerial disinfection systems may vary in terms of operating concentration and mode of delivery. Aim To assess the efficacy of two HPV systems (HPS1 and HPS2) for whole-room aerial disinfection of single isolation rooms (SIRs). Methods Ten SIRs were selected for manual terminal disinfection after patient discharge. Test coupons seeded with biological indicator (BI) organisms [∼10 6 colony-forming units (cfu) of meticillin-resistant Staphylococcus aureus (MRSA) or Klebsiella pneumoniae , or ∼10 5 cfu Clostridium difficile 027 spores] prepared in a soil challenge were placed at five locations per room. For each cycle, 22 high-frequency-touch surfaces in SIRs were sampled with contact plates (∼25cm 2 ) before and after HPV decontamination, and BIs were assayed for the persistence of pathogens. Findings Approximately 95% of 214 sites were contaminated with bacteria after manual terminal disinfection, with high numbers present on the SIR floor (238.0–352.5cfu), bed control panel (24.0–33.5cfu), and nurse call button (21.5–7.0cfu). Enhanced disinfection using HPV reduced surface contamination to low levels: HPS1 [0.25cfu, interquartile range (IQR) 0–1.13] and HPS2 (0.5cfu, IQR 0–2.0). Both systems demonstrated similar turnaround times (∼2–2.5h), and no differences were observed in the efficacy of the two systems against BIs ( C. difficile ∼5.1log 10 reduction; MRSA/ K. pneumoniae ∼6.3log 10 reduction). Despite different operating concentrations of hydrogen peroxide, MRSA persisted on 27% of coupons after HPV decontamination. Conclusion Enhanced disinfection with HPV reduces surface contamination left by manual terminal cleaning, minimizing the risks of cross-contamination. The starting concentration and mode of delivery of hydrogen peroxide may not improve the efficacy of decontamination in practice, and therefore the choice of HPV system may be based upon other considerations such as cost, convenience and logistics.

Summary Mobile phones and tablet computers may be contaminated with micro-organisms and become a potential reservoir for cross-transmission of pathogens between healthcare workers and patients. There is no generally accepted guidance on how to reduce contamination on mobile devices in healthcare settings. Our aim was to determine the efficacy of the Codonics D6000™ UV-C disinfection device. Daily disinfection reduced contamination on screens and on protective cases (test) significantly, but not all cases (control) could be decontaminated. The median aerobic colony count on the control and the test cases was 52 cfu/25 cm2 (interquartile range: 33–89) and 22 cfu/25 cm2 (10.5–41), respectively, before disinfection.