Monitoring Cleaning and Disinfection PracticesMonitoring Cleaning and Disinfection Practices

John M. Boyce, MDDirector, Hospital Epidemiology & Infection Control

Yale-New Haven Hospitaland

Clinical Professor of MedicineYale University School of Medicine

New Haven, CT

Disclosures: Consultant to Clorox Corporation, 3M Corporation, BIOQUELL PLC. Honoraria from Clorox, 3M. Research support from 3M, Clorox, Crothall

Advances in Environmental Cleaning/DisinfectionAdvances in Environmental Cleaning/Disinfection

• Approaches to monitoring cleaning practices

• Coating surfaces with antimicrobial metals

• Applying products with long-term antimicrobial activity to suppress contamination of surfaces

Role of Environment in Transmissionof Healthcare-Associated Pathogens

• Numerous investigators have provided evidence that contaminated environmental surfaces can contribute to transmission of healthcare-associated infections

Hota B Clin Infect Dis 2004;39:1182Boyce JM J Hosp Infect 2007;65 (Suppl 2):50Weber DJ et al. Am J Infect Control 2010;38 (5 Suppl 1):S25Weber DJ and Rutala WA Infect Control Hosp Epidemiol 2011;32:207Otter JA et al. Infect Control Hosp Epidemiol 2011;32:687Weber DJ et al. Curr Opin Infect Dis 2013;26:338

Improving Cleaning/Disinfection Practices

• Pay close attention to cleaning and disinfection of high-touch surfaces in patient-care areas

• Ensure compliance by housekeeping staff with cleaning and disinfection procedures

• Disinfect (or clean) environmental surfaces on a regular basis, and when surfaces are visibly soiled

Sehulster L et al. MMWR Recomm Rep 2003;52(RR-10):1 Rutala WA, Weber DJ et al. HICPAC Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

Methods for Assessing Cleaning Practices

• Visual inspection of surfaces– Check lists sometimes used

• Observation of housekeeper technique

• Fluorescent marker system

• Aerobic colony counts

• ATP bioluminescence assays

Griffith CJ et al. J Hosp Infect 2000;45:19Cooper RA et al. Am J Infect Control 2007;35:338Dancer SJ J Hosp Infect 2009;73:378Luick L et al. Am J Infect Control 2013;41:751

Check lists to Improve Cleaning Practices

http://www.cdc.gov/hai/toolkits/evaluating-environmental-cleaning.html

Visual Inspection of Surfaces

• Simple, can be conducted in any facility

• Usually performed by housekeeping managers

• Assess surfaces to detect visible dirt/stains

• Problem: Surfaces that appeared clean by visual inspection often failed to pass criteria for cleanliness when tested by objective measures: aerobic colony counts or ATP bioluminescence

Griffith CJ et al. J Hosp Infect 2000;45:19Cooper RA et al. AJIC 2007;35:338Luick L et al. AJIC 2013;41:751

Observation of Housekeeper Technique

• Covert or overt observation of housekeepers during routine cleaning/disinfection activities– Establish variations in amount of time spent cleaning or

disinfecting high-touch objects

– Determine number of disinfectant wipes used/room

– Detect which surfaces are not wiped adequately

– Establish if housekeepers are allowing disinfectant to remain on surfaces for appropriate contact time

Hayden MK et al. Clin Infect Dis 2006;42:1552Boyce JM et al. ICHE 2010;31:99Guerrero D et al. 2010 Decennial conference, Abstr 60

Observation and Supervision of Housekeeper Performance

• Investigators applied C. difficile spores (non-toxigenic) to 3 high-touch surfaces in mulitple rooms before terminal cleaning

• Phase 1: housekeepers were not observed and were unaware

• Phase 2: Housekeeper education and direct monitoring of practice

• Phase 3: Direct supervision by investigator, reinforcement of education and real-time feedback

• Results: Education and passive observation sigificantly improved disinfection

• Further significant reduction in contamination occurred with direct supervision and real-time feedback significantly improved disinfection

Guerrero DM et al. ICHE 2013;34:524

Percent of inoculated surfaces positivefor C. difficile after cleaning, with

different interventions

Aerobic Colony Counts

• Methods of culturing environmental surfaces – Moistened swab inoculated onto agar +/- broth enrichment

• Most useful for irregularly shaped surfaces

– Agar contact plates (Rodac)• Recommended for flat surfaces• Yield number of colonies per square inch or centimeter

• Currently, no standard methods for how to obtain & to process specimens for aerobic colony counts– Provide data on contamination by important pathogens

• No accepted criteria for defining a surface as “clean” by using aerobic colony counts

Sehulster L et al. MMWR Recomm Rep 2003;52(RR-10):1Dancer SJ J Hosp Infect 2004;56:10

Moistened Swab with Direct Plating

VRE on Bedside Rail

• Use moistened swab to sample surfaces• If defined area not sampled; results are at best semi-quatitative• If a defined area is sampled using a template, results are quantitative (CFUs/cm2); preferable

• Moistening (wetting) agents include normal saline, broth media (most common), or broth containing disinfectant neutralizer(s)

• Swab is used to directly inoculate non-selective or selective media, followed by incubation x 48 hrs

• Useful for sampling irregularly shaped objects, medical equipment, hard to reach areas, HCP hands

Lemmen SW et al. Int J Hyg Environ Health 2001;203:245Duckro AN et al. Arch Intern Med 2005;165:302Donskey CJ et al. N Engl J Med 2009;360:e3

Hand imprint culture

Aerobic Colony Counts Using RODAC Plates

• RODAC plates are small petri plates filled with agar in order to provide convex surface for sampling flat environmental surfaces

• Agar surface is pressed against a flat surface, plate is incubated

• Advantages:– Very easy to perform; more standardized approach than others– Results can be expressed as CFUs/cm2 (quantitative result)– May be preferable for detecting Gram-positive bacteria (e.g.,

MRSA)– Neutralizer – containing media (Dey-Engley) are available

• Disadvantages:– Greater cost; limited media available; sample small area per

plate

Obee P et al. J Hosp Infect 2007;65:35Rutala WA et al. ICHE 2010;31:1025Galvin S et al. J Hosp Infect 2012;82:143Havill NL Am J Infect Control 2013;41:S26Anderson DJ et al. ICHE 2013;34:466

RODAC Plates

Cultures of Overbed Table

Before Cleaning After Cleaning

Boyce JM et al. SHEA 2011, Abstr 4711

Fluorescent Marker System for Monitoring Cleaning Practices

• Prospective study conducted in 3 hospitals

• 12 high-touch objects in patient rooms were marked with invisible fluorescent solution after terminal cleaning– Marks moistened by disinfectant spray could be removed by

wiping surface for 5 seconds with light pressure

• After at least 2 patients had occupied the rooms and rooms were terminally cleaned, target surfaces were evaluated using a portable UV light to see if the marker had been wiped off

• Intervention: education and feedback given to cleaning staff

Carling PC et al. J Hosp Infect 2008;68:3

Improving Cleaning Practices by Using Fluorescent Marker System

• 1404 objects were evaluated before the intervention

• 744 objects were evaluated after the intervention

• Proportion of objects cleaned– Before intervention: 47%– After interventions: 76 - 92%

• Technique improved in all 3 hospitals (p < 0.001)

• This method has been used to improve cleaning practices in several larger studies

Carling PC et al. Clin Infect Dis 2006;42:385Carling PC et al. Infect Control Hosp Epidemiol 2008;29:1Carling PC et al. Crit Care Med 2010;38:1054

Improving Cleaning Practices by Using Fluorescent Marker System

• Prospective study in 36 acute-care hospitals

– Hospital size: 25 to 721 beds

• Fluorescent markers applied to 14 types of objects before terminal room disinfection

• 20,646 surfaces checked after terminal cleaning

• Intervention included providing housekeepers with performance feedback

Carling PC et al. ICHE 2008;29:1035

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Baseline Post-Intervention

Evaluating Cleaning Measures in an ICU Using Fluorescent Marker System

• Prospective study of the impact of cleaning interventions on environmental contamination by MRSA and VRE

• Intervention consisted of– Change from use of pour bottles to bucket immersion of cleaning cloths– Educational campaign for housekeepers– Feedback regarding adequacy of terminal room cleaning

• 15 surfaces in rooms were marked with a fluorescent dye, and 6 surfaces in patient rooms were cultured for MRSA and VRE

• Results: – Removal of fluorescent dye occurred on

• 44% of surfaces during baseline period• 71% of surfaces during intervention period

– Cultures (+) for MRSA or VRE decreased from 45% at baseline to 27%

Goodman ER et al. Infect Control Hosp Epidemiol 2008;29:593

Evaluating Cleaning Measures in an ICU Using Fluorescent Marker System

Goodman ER et al. Infect Control Hosp Epidemiol 2008;29:593

Monitoring Hospital CleanlinessUsing ATP Bioluminescence Assays

• ATP bioluminescence assays have been used to monitor cleanliness of surfaces in hospitals– Daily cleaning or terminal cleaning– Assess variations in housekeeper performance

Griffith CL et al. J Hosp Infect 2000;45:19Malik RE et al. AJIC 2003;31:181Cooper RA et al. AJIC 2007;35:338Lewis T et al. J Hosp Infect 2008;69:156Boyce JM et al. Infect Control Hosp Epidemiol 2009;30:678Boyce JM et al. Infect Control Hosp Epidemiol 2010;31:99Moore G et al. AJIC 2010;38:617Havill NL et al. AJIC 2011;39:602Anderson RE et al. J Hosp Infect 2011;78:178

ATP Bioluminescence Method

Step 1 Step 2 Step 3

Use special swab Place swab in Place tube in luminometer to sample surface reaction tube Results: Relative Light Units

Assessing Terminal Cleaning Practices Using 3 Methods

• Prospective study to compare how many surfaces would be considered clean, based on – Aerobic colony counts obtained by agar contact plates– Fluorescent marker method– ATP bioluminescence assay system

• 5 high-touch surfaces were sampled in a convenience sample of 100 hospital rooms

• Adjacent surfaces on 5 high-touch surfaces were sampled before and after terminal cleaning

Boyce JM et al. ICHE 2011;32:1187

Assessing Terminal Cleaning Practices Using 3 Methods

• Main outcome measures expressed as percent of surfaces sampled after cleaning with:– Aerobic colony count < 2.5 cfu/cm2

– Most or all of fluorescent marker removed– ATP reading of < 250 Relative Light Units

Proportion of 500 High-Touch Surfaces Classified as Having Been Cleaned by Fluorescent Marker, or as “Clean” by

ACC or ATP Criteria After Terminal Cleaning

75.6 76.8

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ACC ATP

P < 0.0001

P = 0.65

Proportion of 382 High-Touch Surfaces Classified as Having Been Cleaned by Fluorescent Marker, or

Clean by ATP After Terminal Cleaning

74.8

38.9

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Rooms Classified as Clean BEFORE terminal cleaning by ATP were excluded

P < 0.0001

382 High-Touch Surfaces Classified as Not Clean Before Terminal Cleaning,

Results for Fluorescent Marker and ATP

0102030405060708090

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Wiped Off PartiallyWiped

Not Wiped

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ATP < 250

N = 168 N = 124 N = 90

(53.6%) (34.7%)

(6.7%)

Boyce JM et al. ICHE 2011;32:1187

Re-Evaluating Cutoffs for Defining Cleanliness,ATP Bioluminescence and Aerobic Colony Counts

Note: Each graph represents 1000 data points

Boyce JM et al. APIC Annual meeting, 2013, Poster 1705

• Cleaning by housekeepers, using Quat disinfectant

Re-Evaluating Cutoffs for Defining Cleanliness,ATP Bioluminescence and Aerobic Colony Counts

• Cleaning by infection preventionist, using peroxide-based disinfectant

Note: Each graph includes 720 data points (data are for after cleaning only)

ATP Bioluminescence for Evaluating Disinfectionof C. difficile Isolation Rooms

• 140 high-touch sites in 50 rooms were cultured for C. difficile and sampled using an ATP assay after terminal or daily cleaning using bleach-based disinfectant

– Surfaces with ATP < 250 RLU were considered to be clean

• 3% of 71 sites with ATP readings of < 250 RLU had positive culture

19% of 69 sites with ATP readings > 250 RLU had positive culture

• Measuring ATP on surfaces could be a useful & rapid method to assess cleaning of C. difficile rooms

Deshpande A et al. Infect Control Hosp Epidemiol 2013;34:865

Luick L et al. AJIC 2013;41:751

Comparison of Visual Inspection, Fluorescent Marker, Aerobic Colony Counts and ATP Bioluminescence

• 250 environmental surfaces in 50 rooms were sampled after terminal cleaning using three monitoring methods

– Aerobic colony counts [ACC] (before & after cleaning) – Fluorescent markers (checked for complete removal after cleaning)– ATP bioluminescence assay system (before & after cleaning)

• Results: – 93% of surfaces had no visible contamination after cleaning

– 76% were considered clean by ATP method after cleaning

– 87% were considered clean by ACC after cleaning

• Sensitivity, specificity and NPV of methods, compared to ACC– Fluorescent marker: sensitivity = 75%, specificity = 40%, NPV = 28%– ATP: sensitivity = 76%, specificity = 35%, NPV = 26%

• Conclusion: Fluorescent marker and ATP are better than visual assessment. Both may be useful for monitoring cleaning

Caveats on Using ATP Bioluminescenceto Monitor Environmental Cleaning

• No standard, evidence-based criteria for defining surfaces as clean by ATP bioluminescence is currently available

• Cut-offs used to classify surfaces as clean by ATP assays depends on the brand of assay used– Some systems classify surfaces with < 250 RLU as clean

– Other systems classify surfaces with < 100 RLU as clean

– Sensitivity and specificity of different luminometers and assay systems differ

• Consider manufacturer’s recommendations for cut-off

– Further research is needed to refine criteria for cleanliness, both by ATP assays and by aerobic colony counts

Mulvey D et al. J Hosp Infect 2011;77:25Aiken ZA et al. Infect Control Hosp Epidemiol 2011;32:507Shama G et al. Int J Hyg Environmental Health 2013;216:115

Havill NL Am J Infect Control 2013;41:S26

Advantages and Disadvantages of Methods for Monitoring Cleaning and Disinfection Practices

Housekeepers may “game” system

Sequential Interventions and Use of Two Monitoring Methods Improved Disinfection of C. difficile Isolation Rooms

• 21-month prospective intervention trial was conducted to evaluate methods for disinfection of C. difficile isolation rooms

– Phase 1) Fluorescent markers + education and feedback to housekeepers– Phase 2) Addition of automated UV light units for adjunctive disinfection– Phase 3) Use of dedicated daily disinfection team, and requiring rooms to be

“cleared” by housekeeper supervisor or infection preventionist using • visual assessment and • ATP bioluminescence assay of 3 sites in each room

• Surfaces were cultured for presence of C. difficile

• Results: Percent of rooms with positive C.difficile cultures:– Baseline: 67%– Phase 1: 57%– Phase 2: 35%

– Phase 3: 7%

Sitzlar B et al. Infect Control Hosp Epidemiol 2013;34:459

Sequential Interventions and Use of Two Monitoring Methods to Improve Disinfection of C. difficile Isolation Rooms

Sitzlar B et al. Infect Control Hosp Epidemiol 2013;34:459

Conclusions• Contaminated environmental surfaces can contribute to

transmission of healthcare-associated pathogens

• Monitoring cleaning and disinfection of environmental surfaces is recommended in national guidelines

• Visual inspection correlates poorly with objective methods

• Fluorescent marker methods and ATP bioluminescence are being used increasingly to monitoring cleaning– Each method has advantages and limitations

– Can be used in combination

• Aerobic colony counts are more expensive and require more time, but provide unique information– Have been used during outbreaks and for research purposes

Coating Surfaces with Antimicrobial Metals

• Coating medical equipment with metals which have antimicrobial activity is a new strategy for reducing environmental contamination

• Examples include:– Copper alloys (studied most extensively)– Silver or nano-silver particles + titanium dioxide– Zinc

Dancer SJ Eur J Clin Microbiol Infect Dis 2011;30:1473Weber DJ et al. ICHE 2012;33:10

Copper Alloys as Antimicrobial Surfaces

• Environmental surfaces or medical equipment coated with copper alloys have been shown to– Have sustained antimicrobial activity– Reduce levels of bacterial contamination of surfaces in

clinical settings when compared with usual equipment– Effective against a variety of pathogens

• Less effective against MRSA and C. difficile

Noyce JO et al. J Hosp Infect 2006;63:289Wheeldon et al. J Antimicrob Chemother 2008;62:522Casey AL et al. J Hosp Infect 2010;74:72Grass G et al. Appl Environ Microbiol 2011;77:1541Karpanen TJ et al. ICHE 2012;33:3

Antimicrobial (Self-Disinfecting) Surfaces Are Promising, But Require Further Study

• Many of the proposed products yielded only modest killing of pathogens

• Not proven to be effective against some important pathogens (e.g. C. difficile)

• Cost of installing metal-coated equipment and of products applied to usual equipment not clear

• Durability of antimicrobial activity of such products has not been established

• No data on impact of such strategies on HAIs

Weber DJ et al. ICHE 2012;33:10

Applying of Compounds with Long-Term Antimicrobial Activity to Surfaces

• Silver iodide-based compound• Triclosan• Quaternary ammonium salt-based surfactant• Organosilane compounds

– Quaternary ammonium + silicone-based compound– Effective in a few trials, but not in another

• Light-activated antimicrobial coatings– Toluidine blue O + rose Bengal

Weber DJ et al. ICHE 2012;33:10Havill NL & Boyce JM (unpublished)