26/06/2010. Why the debate over HAI and hospital cleaning? Measuring the effect of targeted cleaning. It s not rocket science.. is it?

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1 Measuring the effect of targeted cleaning It s not rocket science.. is it? Dr Stephanie Dancer, NHS Lanarkshire, Scotland Why the debate over HAI and hospital cleaning? There is no evidence: cleaning has never been regarded as an evidence-based science Aesthetic considerations make cleaning difficult to assess No way of measuring the cleaning process or its impact on the environment Confounded by fabric and maintenance deficits It costs money We cannot see the enemy Cleaning has always been taken for granted Properties of hospital pathogens Survival time Infectious dose MRSA 7 days to 7 months 4 cfu s Acinetobacter 3 days to 5 months 250 cfu s C.difficile 5 months 7 spores VRE 5 days to 4 months <10 3 cfu s Norovirus 8 hours to 7 days Kramer, BMC Infect Dis, 2006; Dancer SJ, LID 2008; Chiang Crit Care Med 2009; Wilcox M, 2010; Larson, Lancet 1978; Kjerulf et al, APMIS 1998 Where are the pathogens in a hospital? C.difficile, VRE and MRSA are found on hand-touch sites in the clinical environment Microbes can survive on surfaces for months. X denotes tested surfaces Hayden et al, SHEA

2 It is almost as easy to pick up MRSA by touching a patient's environment as it is by touching the patient What s so important about hand touch surfaces? These are the places to find transmissible microbes! Frequently used hand-touch surfaces are high-risk surfaces The closer the surface is to a patient, the more critical it is likely to be Biotrace, 2003 MRSA, VRE or C.difficile in this room may be acquired by the next patient Boyce et al, ICHE 1997; Huang et al, Arch Intern Med 2006; Drees et al, ICHE 2008; Hayden et al, ICHE 2008 Detection of pathogen transmission in neonatal nurseries using DNA markers as surrogate indicators (Oelberg DG et al, Paediatrics 2000); Transportation of viruses via contact using bacteriophage OX174 as a model virus (Rheinbaben F et al, J Hosp Infect 2000) Are hand-touch sites routinely cleaned? Routine cleaning practices were assessed by applying a fluorescent solution to different sites in side-rooms. These sites were evaluated following patient discharge; a site was considered cleaned if the fluorescent material was removed. Although 40% sites were cleaned properly, they tended to be the more traditional sites (toilets and sinks) whereas sites such as telephones, doorknobs and other hand-touch surfaces were scarcely cleaned at all. Carling et al, Am J Infect Control 2006 So.. let s clean the near patient hand-touch sites But how do we know if cleaning is effective? How do we monitor cleanliness? What is clean? Assessment of cleanliness: are there lessons from the food industry? How clean are hospital surfaces? 82-91% Visually clean 10-24% ATP clean 30-45% Microbiologically clean What is clean? what an individual thinks it is We should not define cleanliness without indicating how we would assess it Griffith CJ, Biomed Scientist 2006 Griffith CJ et al, J Hosp Infect

3 Surface evaluation using ATP bioluminescence Swab surface luciferase tagging of ATP Hand held luminometer Used in the commercial food preparation industry to evaluate surface cleaning before reuse and as an educational tool for more than 30 years. Locker (M) Locker (S) L Bed (M) L Bed (S) O/B Table (M) O/B Table (S) R Bed (M) R Bed (S) Before After Site ATP Before * * Site ATP After * * ATP values for sites on medical and surgical wards before and after detergent-based cleaning Proposal for bacteriological standards for surface level cleanliness in hospitals Microbiological standards for surface hygiene in hospitals Standard 1 There should be <1cfu/cm 2 pathogen (MRSA; C.difficile; VRE; etc) in the clinical environment Standard 2 The Aerobic Colony Count (ACC) or total microbial growth level from a hand contact surface should be <5 cfu/cm 2 5/cm 2 45/cm 2 Slide courtesy of Chris Griffith These standards are based upon food industry counts as applied to food preparation surfaces but could be utilised for frequent hand touch surfaces in hospitals. Dancer S, J Hosp Infect 2004 Bed rail Are microbiological standards helpful? Overbed table Application of microbiological standards on two surgical wards We found S.aureus & MRSA on lockers, overbed tables and beds; finding these at any site was significantly associated with higher microbial growth levels from that site (p=0.001) Total aerobic colony counts (ACC) each week were significantly associated with weekly bed occupancies >95% (p=0.001) Bedside locker We screened ten hand-touch sites on two surgical wards for one year, using the proposed standards Dancer et al, IntJEHR 2008 Microbial dirt on hand-touch sites reflects weekly bed occupancies and indicates a risk for S.aureus & MRSA; these pathogens were far more likely to be recovered from near-patient sites on the ward Dancer SJ et al, Int J EHR

4 Total no. samples 20 Comparison of hygiene fails from hand-touch sites in ICU over a ten week period Cardiac monitor buttons Bed frame Curtain around bed Hand-touch site (x8) Locker Computer keyboard Phone Blood gas analyser Staff chair No. of counts >5cfu/cm No. of MSSA &/or MRSA 3* 5* * 7* Total hygiene fails Eight sites were screened weekly x2 for 10 weeks; indicator organisms were MSSA & MRSA; * PFGE match between hand-touch site and patient isolates Conclusions from ICU study One quarter of 200 samples failed the standards, mostly from hand-touch sites. Hygiene fails were associated with bed occupancy (p=0.04) and there was a trend towards association with all ICU-acquired infection (p=0.11). Environmental S.aureus was positively associated with proportion of beds occupied (p=0.02). There were indistinguishable genotypes found between patient and environmental staphylococci, with timescales supporting transmission in both directions. Hygiene standards reflect patient activity and provide a means to risk manage infection. White et al, AmJIC 2008 Is there a relationship between microbiological standards and ATP values from surfaces? Measuring ATP levels can tell you how good the general cleaning is AND encourages cleaners to improve their cleaning efficiency But - there is no point routinely measuring ATP levels from hospital surfaces if there isn t going to be any benefit for patients White et al, AmJIC 2008 Relationship between aerobic colony count on a surface and its pass or fail using either ATP assessment (grey bars; fail if >250 relative light units) or visual assessment (black bars). Graph shows percentage of fails by ATP and visual assessment for each range of aerobic colony count % fails % ATP Aerobic colony count (cfu/cm2) Lewis et al, JHI 2008 Mulvey et al, report in preparation

5 W a r d A W a r d B Reduction in VRE after improving cleaning & hand-hygiene What is the evidence for cleaning as a viable control mechanism for hospital-acquired infections? Rate of hospital-acquired Clostridium difficile associated diarrhoea in a medical ICU over a 3 year period What is the evidence that cleaning reduces the risk of MRSA acquisition? McMullen K et al, ICHE 2007 Rampling et al, J Hosp Infect 2001 What is the evidence for cleaning as a viable control mechanism for hospital-acquired infection? We introduced one extra cleaner into two matched wards from Monday to Friday, with each ward receiving extra detergentbased cleaning for six months in a prospective cross-over design Total aerobic colony colony count from count ten hand-touch from ten sites handtouch sites on matched two matched surgical wards surgical on two wards T o tal aero bic co lo ny co unt fro m ten hand-to uch sites o n 100 two matched surgical wards Ten hand-touch sites on both wards were screened weekly using the standards and patients were monitored for MRSA infection throughout the year-long study Total ACC Weeks 20 BBC website, 2008 Patient and environmental MRSA isolates were characterized using DNA fingerprinting Dancer et al, BMC Med Weeks Ward A Ward B Dancer et al, BMC Med,

6 Where were S.aureus and MRSA? Sites more frequently contaminated with S.aureus and MRSA were: bedside locker (17 isolates) overbed table (13 isolates) bed frame (12 isolates) These are all near-patient sites Priority should be given to improving decontamination of sites around the patient's bedside. These are the sites that are both frequently contaminated and frequently touched, thereby making them important for transferring bacteria to patients. Peter Obee, PhD thesis, 2009 What did we find? One extra cleaner was responsible for a 33% reduction in aerobic colony counts on hand-touch sites and 27% reduction in new MRSA infections, despite busier wards and more MRSA patient-days Adjusting for MRSA patient-days and based upon 9 new MRSA infections found during routine cleaning, we expected 13 new infections with the extra cleaning rather than the four that actually occurred DNA fingerprinting confirmed indistinguishable strains from both hand-touch sites and patients; some of these were isolated months apart DYNAMIC TRANSMISSION CYCLE OF HOSPITAL PATHOGENS Patients (infected and/or colonised) Antibiotic Pressures Berntsen et al, NEJM 1960; Cheng et al, JHI 2008 Hands (whose?) Environment including air What s on YOUR hands??! The Hand-Touch equation = Hand Hand-touch site Even if you keep your hands clean ALL THE TIME, any benefits from hand hygiene are eroded if there is MRSA on the very next surface you touch Bobulsky G et al, CID 2007; Farr et al, LID 2001 WHY is all the emphasis on cleaning hands and not on cleaning the things that they touch? 6

7 So, what should we do to get our hospitals cleaner? 8 reports Visual inspections Direct observation 10 studies Supervision 11 studies Disinfectants Fluorescent gel 8 reports ATP bioluminescence monitoring Microbiological monitoring 4 studies Something for the 21st century And always, always, always, more scientific evidence Carling et al, AmJIC June 2010 Disinfectants vs Detergents Disinfectants do not degrade Expensive & toxic Incite mutation and resistance Are there less toxic alternatives? Microfibre: recontamination; decontamination Moore & Griffith, JHI 2006; Wren et al, JHI 2008; Bergen et al, JHI 2009 Steam: operator dependent; electrical items; aerosol potential Meunier et al, Pathol Biol 2008; Griffith & Dancer, JHI 2009 Hydrogen peroxide: expensive; single rooms only; not fabrics Shapey et al, J Hosp Infect 2008 UV light: expensive; inadequate for C.difficile spores Geuerrero et al, SHEA 2010 What does bleach do to microfibre? Scanning electron micrographs of ultra microfibre (UMF) cloths treated for 16 h. The UMF fibres are intact after exposure to water but the fibres have been severed after exposure to Chlor-Clean. Magnification: 400. Havill et al, SHEA 2010 Evaluation of decontamination efficacy of microfibre cloth compared with other cleaning cloths in the hospital The cleaning effect of microfibre cloths was compared against cotton cloths after 10 and 20 times of reprocessing both types of cloths. When new, microfibre cloths were better than cotton cloths, but cotton cloths showed much better decontamination compared with microfibre cloths using S. aureus (p=0.0334; regression coefficient ) and E. coli (p=0.0014; regression coefficient ) after being reprocessed 20 times. Gant VA et al, J Hosp Infect 2010 Diab-Elschahawi et al, AMJIC

8 Hey! Back to the future Monitoring the effectiveness of hospital cleaning practices by use of an ATP bioluminescence assay Thoroughness of Terminal Room Environmental Cleaning % GOAL % 60 CLEAN Bar graph of ATP readings, expressed as relative light units, from 5 high-touch surface samples after daily cleaning; phase I (striped bars) and phase II (solid bars) 0 PRE PHASE II PHASE III Boyce et al, ICHE 2009 Carling et al, AMJIC 2010 Conclusion Hospital infection and inadequate hospital cleaning are linked High risk sites are near-patient hand-touch sites We know which sites need cleaning, but not necessarily how we should clean them or how often How should we assess hospital cleaning? Find the evidence for soap and water first, before powerful disinfectants destroy our environment Hands are important because they touch patients and surfaces we need clean hands AND clean surfaces?#@%*?!+#?! Acknowledgements Michael Coyne and Lisa White Karen Jennings and colleagues at UNISON Dr Penelope Redding Professor Chris Robertson Professor Phil Carling Microbiology, Southern General Hospital Health Facilities Scotland Beth Anderson Please note that the views expressed in this presentation are not necessarily representative of the views of the Hospital Infection Society nor NHS Lanarkshire 8

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