Transcript The Benefits of Surface Disinfection

The Benefits of Surface Disinfection
William A. Rutala, Ph.D., M.P.H.
UNC Health Care System and UNC School of Medicine,
Chapel Hill, NC
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection
Introduction and principles of disinfection
 Review the contribution of the noncritical environment to
disease transmission
 Justify the use of a disinfectant on noncritical surfaces
 Provide recommendations for surface disinfection
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Copyright © 2004 WA Rutala
Disinfection
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Introduction
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Effective use of disinfectants constitutes an important factor in preventing
healthcare-associated infections
Spaulding proposed three categories of germicidal action to prevent a risk
of infection associated with the use of equipment or surfaces
Three categories: critical; semicritical; noncritical
Surfaces considered noncritical (contact intact skin)
Use of noncritical items or contact with noncritical surfaces carries a low
risk of transmitting a pathogen to patients
Copyright © 2004 WA Rutala
Surface Disinfection
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Noncritical Surfaces
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Medical equipment surfaces (BP cuff, stethoscopes)
May
frequently become contaminated with patient material
Repeatedly touched by health care personnel
Disinfectant may be used
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Housekeeping surfaces (bed rails, bedside tables)
May
play a theoretical but less significant role in diseases transmission
Disinfectants or detergents may be used
Copyright © 2004 WA Rutala
Low Level Disinfection for
“Noncritical” Objects
Exposure time >60 sec
Germicide
Use Concentration
Ethyl or isopropyl alcohol
70-90%
Chlorine
100ppm (1:500 dilution)
Phenolic
UD
Iodophor
UD
Quaternary ammonium
UD
_____________________________________
UD=Manufacturer’s recommended use dilution
Copyright © 2004 WA Rutala
Surface Disinfection
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Introduction (continued)
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Use of noncritical items or contact with noncritical surfaces carries little risk
of transmitting pathogens to patients
Thus, the routine use of disinfectants to disinfect housekeeping surfaces
(e.g., bedside tables, bed rails) is controversial
However, while noncritical surfaces have not been directly implicated in
disease transmission, they may potentially contribute to cross-transmission
by acquisition of transient hand carriage by HCW due to contact with a
contaminated surface, or patient contact with contaminated surfaces or
medical equipment
Copyright © 2004 WA Rutala
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection
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Justification for Using a Disinfectant
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Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and surfaces for
patients on isolation precautions
One product for decontamination of noncritical surfaces (that is, floors
and equipment)
Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
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Pathogens implicated in transmission via contaminated noncritical surfaces
Bacteria
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Acinetobacter, Pseudomonas, Clostridium difficile
Oxacillin-resistant Staphylococcus aureus
 Vancomycin-resistant Enterococcus spp.
Viruses
 SARS
 Rotavirus
 Respiratory syncytial virus (RSV)
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Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
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Why do we believe that surfaces may contribute to
transmission of epidemiologically important microbes
(e.g., VRE)?
Does VRE survive in the environment?
 Are surfaces near infected/colonized patients contaminated and
does surface contamination play a role in patient-to-patient
transmission?
 Are there trials demonstrating reduced transmission with
disinfection?
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Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
VRE ENVIRONMENTAL SURVIVAL
Enterococcus
 Countertops: E. faecalis = 5 d, E. faecium = 7 d
 Bedrails = 24 hours
 Telephone handpieces = 60 minutes
 Stethoscopes = 30 minutes
 Gloved and ungloved fingers >60 minutes
Noskin G, et al. ICHE 1995;16:577-581.
Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
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Why do we believe that surfaces may contribute to
transmission of epidemiologically important microbes
(e.g., VRE)?
Does VRE survive in the environment?
 Are surfaces near infected/colonized patients contaminated and
does surface contamination play a role in patient-to-patient
transmission?
 Are there trials demonstrating reduced transmission with
disinfection?
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Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
VRE ENVIRONMENTAL CONTAMINATION
Reference
Karanfil 1992
Sites Contaminated
EKG pressure monitor
dials, doorknob
Boyce 1994
Patient gowns, linens,
bedrails, IV pumps, BP cuff
Boyce 1995
Patient gowns, linens,
bedrails, BP cuff, IV pump
Slaughter 1996 Bed linen, siderails, BP
cuffs, bedside tables
Frequency
12%
28%
37%
7%
Weber DJ, Rutala WA. ICHE 1997;18:306-309.
Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
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Why do we believe that surfaces may contribute to transmission of
epidemiologically important microbes (e.g., VRE)?
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Does VRE survive in the environment?
Are surfaces near infected/colonized patients contaminated and does
surface contamination play a role in patient-to-patient transmission?
Do antibiotic-resistant organisms (e.g., VRE) develop cross-resistance to
commonly used environmental disinfectants or antiseptics?
Are there trials demonstrating reduced transmission with disinfection?
Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
Surfaces in the Spread of Infections
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In experimental settings, treatment of surfaces with germicide has been
found to interrupt transmission
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Prevention of surface-to-human rotavirus transmission by treatment with disinfectant
spray (J Clin Microbiol 1991;29:1991)
Interrupts transfer of rhinovirus from environmental surfaces to hands (Appl Environ
Microbiol 1993;59:1579)
Studies demonstrating reduced transmission with improved disinfection
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Aggressive environmental control program credited with eradicating VRE from a burn
unit and Acinetobacter from a neurosurgical ICU
Reduction in C. difficile-associated diarrhea rates in the BMTU (8.6 to 3.3) during the
period of bleach disinfection (1:10)
Copyright © 2004 WA Rutala
Surfaces May Contribute to Transmission
CONCLUSIONS
Widespread surface contamination may occur with some
pathogens (e.g. VRE) and hands may become transiently
colonized from contact with surfaces
 Noncritical surfaces may play a role in the transmission of
some pathogens (e.g., VRE, C.difficile)
 Meticulous disinfection and handwashing will prevent
transmission
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Copyright © 2004 WA Rutala
Impact of Surface Disinfection on HAIs
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Dharan et al, 1999
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Danforth et al, 1987
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No change in incidence of HAIs during 4 mo trial compared to preceding 12 mo;
but detergents associated with increase in bacterial counts.
NI rate did not differ between disinfectant (8.0/100 patients) and detergent
(7.1/100 patients); 8 acute care units; 3 mo periods; phenol.
Daschner et al, 1980
No difference in NI rate in ICU over 6 mo (15.6% vs 15.5%).
Comment: Studies are small, short duration and suffer from low statistical power since the
outcome (HAI) is one of low frequency (not detect small decrease-0.1%, 1750 HAIs).
Requirement for reducing HAI stringent, not met by most infection control
interventions.
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Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant
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Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and surfaces for
patients on isolation precautions
One product for decontamination of noncritical surfaces (that is, floors
and equipment)
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection
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Needed for surfaces contaminated by blood and OPIM
In the US, to comply with OSHA rule on bloodborne
pathogens, a blood spill must be cleaned using a disinfectant
 The compliance directive states that the blood should be
disinfected using an EPA-registered disinfectant, a
disnfectant with a HBV/HIV claim, or a solution of bleach
between 1:10 and 1:100 with water.
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Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant

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
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

Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and surfaces for
patients on isolation precautions
One product for decontamination of noncritical surfaces (that is, floors
and equipment)
Copyright © 2004 WA Rutala
Cleaning and Disinfection of Floors
% Reduction
Soap and water
80.4%
Phenol
99.0%
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant






Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and surfaces for
patients on isolation precautions
One product for decontamination of noncritical surfaces (that is, floors
and equipment)
Copyright © 2004 WA Rutala
Microbial Contamination of Mop Water
Before cleaning
Soap
(CFU/ml)
10
After cleaning one- 650
third of ward
After cleaning two- 15,000
thirds of ward
After cleaning
34,000
complete ward
Phenol
(CFU/ml)
20
10
30
20
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant
Surfaces may contribute to transmission of epidemiologically
important microbes (e.g., VRE, MRSA, C. difficile)
 Needed for surfaces contaminated by blood and OPIM
 Disinfectants are more effective in reducing microbial load
 Detergents become contaminated and result in seeding the
patients environment with bacteria

Dharan
found use of detergents alone on floors and furniture led to
an increase in contamination in patients environmental surfaces
after cleaning (average increase 103.6cfu/24cm2)
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant






Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and
housekeeping surfaces for patients on isolation precautions (eg, MRSA)
One product for decontamination of noncritical surfaces (that is, floors
and equipment)
Copyright © 2004 WA Rutala
Recommendations for Surface Disinfection
Europe
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Dettenkofer, Merkel, Mutter, Daschner – 2004
Recommended that the MRSA patient room be disinfected 3
times per day on intensive care units and once per day on
normal wards
 But given the high prevalence of MRSA among hospitalized
patients in many countries and routine screening is rarely
conducted, shouldn’t we employ disinfectants for all
hospitalized patients as unspecified colonization is a routine
occurrence?
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Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Justification for Using a Disinfectant






Surfaces may contribute to transmission of epidemiologically important
microbes (e.g., VRE, MRSA, C. difficile)
Needed for surfaces contaminated by blood and OPIM
Disinfectants are more effective in reducing microbial load
Detergents become contaminated and result in seeding the patients
environment with bacteria
CDC recommends disinfection of noncritical equipment and surfaces for
patients on isolation precautions
One product for decontamination of noncritical surfaces (that is,
noncritical housekeeping and equipment, isolation, blood)
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection

Reasonable to use hospital disinfectants on noncritical
patient equipment surfaces (e.g., blood pressure cuffs,
stethoscopes, radiograph machines), and housekeeping
surfaces (e.g., bedside tables and bed rails).
Copyright © 2004 WA Rutala
Recommendations for Surface Disinfection
Europe
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Robert Koch Institute, Germany
Tasked to produce guidelines by a federal infection protection
law
 Recommends the use of surface disinfectants for patient
equipment surfaces and noncritical housekeeping surfaces in
patient care areas.
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French Authorities
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Recommends using disinfectants for surface disinfection in
patient care areas
Copyright © 2004 WA Rutala
Surface Disinfection
Concerns?
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Allergy-Literature review (Medline) from 1966 to April 2004,
provided no evidence that suggests the use of LLD results in
allergic symptoms in health care workers. “BAC is one of the
leading allergens affecting HCP” discussed Quat use as a risk
factor for allergies in pig farmers.
Environment-Adverse effects on human health, due to the disposal
of LLD into soil/rivers/streams, have not been proposed or
demonstrated. EPA does not regulate the discharge of LLD via
waste water.
Increased resistance-No evidence that using LLD selects for
antibiotic-resistant organisms in nature or mutants survive.
Copyright © 2004 WA Rutala
The Benefits of Surface Disinfection
Introduction and principles of disinfection
 Review the contribution of the noncritical environment to
disease transmission
 Justify the use of a disinfectant on noncritical surfaces
 Provide recommendations for surface disinfection

Copyright © 2004 WA Rutala