American Journal of Infection Control 42 (2014) 1002-3
Contents lists available at ScienceDirect
American Journal of Infection Control
American Journal of Infection Control
journal homepage: www.ajicjournal.org
Brief report
How clean is cleandis a new microbiology standard required? Elaine Cloutman-Green MRes a, *, Nikki D’Arcy BSc, PGCert b, David A. Spratt PhD b, John C. Hartley MBBS, MSc, MRCP, DTM&H, FRCPath a, Nigel Klein PhD, MBBS c a
Department of Microbiology, Virology, and Infection Prevention and Control, Camelia Botnar Laboratories, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom b Eastman Dental Institute, University College London, London, United Kingdom c Institute of Child Health, Infectious Diseases and Microbiology Unit, University College London, London, United Kingdom
Key Words: Health care-associated infection Intensive care Health care environment Pediatrics
The role of environment in the spread of nosocomial infection has been acknowledged. One way to control the spread of infection is to control and monitor patient environments to prevent transmission. Studies applying the suggested aerobic colony count standards to monitor environmental contamination were undertaken over an 18-month period at both a London pediatric hospital and in adult intensive care units. The resulting data demonstrate that a large proportion of sites screened for bacterial contamination would fail if using the criteria suggested by previous authorsdparticularly those sites closest to patientsdsuggesting a new standard might be required. Copyright Ó 2014 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Health care-associated infections (HCAIs) can lead to poor clinical outcomes and death. The role of environment in the spread of nosocomial infection has been acknowledged, although the precise contribution to transmission of infection is hard to define.1 Risk to patients from environmental microorganisms depends on host factors, the ability of the organisms to remain viable in the environment, the frequency with which contaminated surfaces are touched, and the levels of contamination present on surfaces.2 Cleaning in health care environments aims to reduce levels of microorganisms to the point at which they do not pose a crosstransmission risk to patients. The only official UK Department of Health guideline to achieving this aim requires assessing if the environment is visibly clean and disinfecting high-contact surfaces regularly. One study3 demonstrated that when 82% of ward sites were visually clean, only 30% of sites were considered clean by microbiologic sampling. Visual inspection of a hospital environment may not, therefore, provide a reliable assessment * Address correspondence to Elaine Cloutman-Green, MRes, Department of Microbiology, Virology, and Infection Prevention, Level 4 Camelia Botnar Laboratory, Great Ormond Street Hospital NHS Foundation Trust, London, WC1N 3JH, United Kingdom. E-mail address: [email protected] (E. Cloutman-Green). EC-G and ND contributed equally to this work. Elaine Cloutman-Green received funding from the National Institute of Health Research during the course of this research (grant No. HCSD10). Nikki D’Arcy was supported by funding from the Engineering and Physical Sciences Research Council. Conflicts of interest: None to report.
of environmental cleanliness or assess the risk of infection to patients.4 Government guidance regarding acceptable numbers of microorganisms on hospital surfaces does not currently exist. Griffith et al5 suggested a site should fail screening and be subject to investigation if it has an aerobic colony count (ACC) > 2.5 CFU/cm2 on an agar contact plate (60 CFU/plate). This cutoff was based on food preparation standards and has been adopted by others.6,7 Dancer8 proposed the cutoff limit of 5 CFU/cm2 (120 CFU/plate) based on US Department of Agriculture limits of bacteria on foodprocessing equipment, with failures leading to bed space closures and repeat cleaning. Dancer and others6,9 have since published articles using the lower cutoff limit of 2.5 CFU/cm2, referring to it as a “standard.” Monitoring of the environment for indicator organisms has been suggested as an alternative standard for assessing cleanliness.8 Indicator organisms could include methicillin-resistant Staphylococcus aureus and carbapenemase-resistant Enterobacteriaceae, which are both indicated in outbreaks and severe infection. Our study applied the suggested ACC standards put forth by Griffith5 and Dancer8 for environmental monitoring to wards and outpatient settings at Great Ormond Street Hospital over 18 months to determine their suitability as part of routine infection control monitoring. To determine if there were differences between pediatric and adult settings, 2 adult intensive care units at a separate London hospital were also tested.
0196-6553/$36.00 - Copyright Ó 2014 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajic.2014.04.025
E. Cloutman-Green et al. / American Journal of Infection Control 42 (2014) 1002-3
1003
Table 1 Summary of ward and outpatient aerobic colony count screening results using the suggested
Contents lists available at ScienceDirect
American Journal of Infection Control
American Journal of Infection Control
journal homepage: www.ajicjournal.org
Brief report
How clean is cleandis a new microbiology standard required? Elaine Cloutman-Green MRes a, *, Nikki D’Arcy BSc, PGCert b, David A. Spratt PhD b, John C. Hartley MBBS, MSc, MRCP, DTM&H, FRCPath a, Nigel Klein PhD, MBBS c a
Department of Microbiology, Virology, and Infection Prevention and Control, Camelia Botnar Laboratories, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom b Eastman Dental Institute, University College London, London, United Kingdom c Institute of Child Health, Infectious Diseases and Microbiology Unit, University College London, London, United Kingdom
Key Words: Health care-associated infection Intensive care Health care environment Pediatrics
The role of environment in the spread of nosocomial infection has been acknowledged. One way to control the spread of infection is to control and monitor patient environments to prevent transmission. Studies applying the suggested aerobic colony count standards to monitor environmental contamination were undertaken over an 18-month period at both a London pediatric hospital and in adult intensive care units. The resulting data demonstrate that a large proportion of sites screened for bacterial contamination would fail if using the criteria suggested by previous authorsdparticularly those sites closest to patientsdsuggesting a new standard might be required. Copyright Ó 2014 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Health care-associated infections (HCAIs) can lead to poor clinical outcomes and death. The role of environment in the spread of nosocomial infection has been acknowledged, although the precise contribution to transmission of infection is hard to define.1 Risk to patients from environmental microorganisms depends on host factors, the ability of the organisms to remain viable in the environment, the frequency with which contaminated surfaces are touched, and the levels of contamination present on surfaces.2 Cleaning in health care environments aims to reduce levels of microorganisms to the point at which they do not pose a crosstransmission risk to patients. The only official UK Department of Health guideline to achieving this aim requires assessing if the environment is visibly clean and disinfecting high-contact surfaces regularly. One study3 demonstrated that when 82% of ward sites were visually clean, only 30% of sites were considered clean by microbiologic sampling. Visual inspection of a hospital environment may not, therefore, provide a reliable assessment * Address correspondence to Elaine Cloutman-Green, MRes, Department of Microbiology, Virology, and Infection Prevention, Level 4 Camelia Botnar Laboratory, Great Ormond Street Hospital NHS Foundation Trust, London, WC1N 3JH, United Kingdom. E-mail address: [email protected] (E. Cloutman-Green). EC-G and ND contributed equally to this work. Elaine Cloutman-Green received funding from the National Institute of Health Research during the course of this research (grant No. HCSD10). Nikki D’Arcy was supported by funding from the Engineering and Physical Sciences Research Council. Conflicts of interest: None to report.
of environmental cleanliness or assess the risk of infection to patients.4 Government guidance regarding acceptable numbers of microorganisms on hospital surfaces does not currently exist. Griffith et al5 suggested a site should fail screening and be subject to investigation if it has an aerobic colony count (ACC) > 2.5 CFU/cm2 on an agar contact plate (60 CFU/plate). This cutoff was based on food preparation standards and has been adopted by others.6,7 Dancer8 proposed the cutoff limit of 5 CFU/cm2 (120 CFU/plate) based on US Department of Agriculture limits of bacteria on foodprocessing equipment, with failures leading to bed space closures and repeat cleaning. Dancer and others6,9 have since published articles using the lower cutoff limit of 2.5 CFU/cm2, referring to it as a “standard.” Monitoring of the environment for indicator organisms has been suggested as an alternative standard for assessing cleanliness.8 Indicator organisms could include methicillin-resistant Staphylococcus aureus and carbapenemase-resistant Enterobacteriaceae, which are both indicated in outbreaks and severe infection. Our study applied the suggested ACC standards put forth by Griffith5 and Dancer8 for environmental monitoring to wards and outpatient settings at Great Ormond Street Hospital over 18 months to determine their suitability as part of routine infection control monitoring. To determine if there were differences between pediatric and adult settings, 2 adult intensive care units at a separate London hospital were also tested.
0196-6553/$36.00 - Copyright Ó 2014 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajic.2014.04.025
E. Cloutman-Green et al. / American Journal of Infection Control 42 (2014) 1002-3
1003
Table 1 Summary of ward and outpatient aerobic colony count screening results using the suggested
