efficacy, selection and use of disinfectants and detergents in environmental cleaning/disinfection...

Efficacy, Selection and Use of Disinfectants and Detergents in Environmental Cleaning/Disinfection

William A. Rutala, PhD, MPHDirector, Hospital Epidemiology, Occupational Health and Safety;

Professor of Medicine and Director, Statewide Program for Infection Control and Epidemiology

University of North Carolina at Chapel Hill and UNC Health Care, Chapel Hill, NC

DISCLOSURES

• Consultation and Honoraria ASP (Advanced Sterilization Products), Clorox

• Honoraria 3M

• Grants CDC, CMS


• Role of the environment in disease transmission• Factors that affect disinfection• Advantages/disadvantages of disinfectants used on

environmental surfaces and non-critical patient equipment• Efficacy of disinfectants• Selection and use of disinfectants

DISINFECTION AND STERILIZATIONRutala, Weber, HIPAC. www.cdc.gov, 2008

• EH Spaulding believed that how an object will be disinfected depended on the object’s intended use CRITICAL - objects which enter normally sterile tissue or the

vascular system or through which blood flows should be sterile SEMICRITICAL - objects that touch mucous membranes or skin

that is not intact require a disinfection process (high-level disinfection[HLD]) that kills all microorganisms except for high numbers of bacterial spores

NONCRITICAL - objects that touch only intact skin require low-level disinfection

DISINFECTION AND STERILIZATION

• EH Spaulding believed that how an object will be disinfected depended on the object’s intended use CRITICAL - objects which enter normally sterile tissue or the

vascular system or through which blood flows should be sterile SEMICRITICAL - objects that touch mucous membranes or skin

that is not intact require a disinfection process (high-level disinfection[HLD]) that kills all microorganisms except for high numbers of bacterial spores

NONCRITICAL - objects that touch only intact skin require low-level disinfection

KEY PATHOGENS WHERE ENVIRONMENTIAL SURFACES PLAY A ROLE IN TRANSMISSION

• MRSA• VRE• Acinetobacter spp.• Clostridium difficile

• Norovirus• Rotavirus• SARS

ENVIRONMENTAL CONTAMINATION LEADS TO HAIsWeber, Rutala, Miller et al. AJIC 2010;38:S25

• Frequent environmental contamination• Microbial persistence in the environment • HCW hand contamination with the environment• Prior room occupant with MRSA, VRE, CDI is a significant risk for

acquisition of these pathogens. • Improved surface disinfection removes pathogens and reduce

HAIs

ENVIRONMENTAL CONTAMINATION ENVIRONMENTAL CONTAMINATION ENDEMIC AND EPIDEMIC MRSAENDEMIC AND EPIDEMIC MRSA

Dancer SJ et al. Lancet ID 2008;8(2):101-13

ENVIRONMENTAL SURVIVAL OF KEY PATHOGENS ON HOSPITAL SURFACES

Pathogen Survival Time

S. aureus (including MRSA) 7 days to >12 months

Enterococcus spp. (including VRE) 5 days to >46 months

Acinetobacter spp. 3 days to 11 months

Clostridium difficile (spores) >5 months

Norovirus (and feline calicivirus) 8 hours to >2 weeks

Pseudomonas aeruginosa 6 hours to 16 months

Klebsiella spp. 2 hours to >30 months

Adapted from Hota B, et al. Clin Infect Dis 2004;39:1182-9 andKramer A, et al. BMC Infectious Diseases 2006;6:130

FREQUENCY OF ACQUISITION OF MRSA ON GLOVED HANDS AFTER CONTACT WITH SKIN AND ENVIRONMENTAL SITES

No significant difference on contamination rates of gloved hands after contact with skin or environmental surfaces (40% vs 45%; p=0.59)

Stiefel U, et al. ICHE 2011;32:185-187

RELATIVE RISK OF PATHOGEN ACQUISITIONIF PRIOR ROOM OCCUPANT INFECTED

0 0.5 1 1.5 2 2.5 3 3.5 4

MDR Acinetobacter (Nseir S, 2011)

C. diff (Shaughnessy M, 2011)

VRE (Drees M, 2008)

MDR Pseudomonas (Nseir S, 2011)

VRE (Huang S, 2006)

VRE* (Dress M, 2008)

MRSA (Huang S, 2006)

* Prior room occupant infected, 120% increased risk; ^Any room occupant in prior 2 weeks infected. Otter , Yezli, French. ICHE. 2012;32:687-699

EVALUATION OF HOSPITAL ROOM ASSIGNMENT AND ACQUISITION OF CDI

Study design: Retrospective cohort analysis, 2005-2006

Setting: Medical ICU at a tertiary care hospital

Methods: All patients evaluated for diagnosis of CDI 48 hours after ICU admission and within 30 days after ICU discharge

Results (acquisition of CDI) Admission to room previously occupied

by CDI = 11.0% Admission to room not previously

occupied by CDI = 4.6% (p=0.002)

Shaughnessy MK, et al. ICHE 2011;32:201-206

TRANSMISSION MECHANISMS INVOLVING THE SURFACE ENVIRONMENT

Rutala WA, Weber DJ. In:”SHEA Practical Healthcare Epidemiology” (Lautenbach E, Woeltje KF, Malani PN, eds), 3rd ed, 2010.

ACQUISITION OF MRSA ON HANDS AFTER CONTACT WITH ENVIRONMENTAL SITES

ACQUISITION OF MRSA ON HANDS/GLOVES AFTER CONTACT WITH CONTAMINATED EQUIPMENT

TRANSFER OF MRSA FROM PATIENT OR ENVIRONMENT TO IV DEVICE AND TRANSMISSON OF

PATHOGEN

TRANSMISSION MECHANISMS INVOLVING THE SURFACE ENVIRONMENT

Rutala WA, Weber DJ. In:”SHEA Practical Healthcare Epidemiology” (Lautenbach E, Woeltje KF, Malani PN, eds), 3rd ed, 2010.

ACQUISITION OF C. difficile ON PATIENT HANDS AFTER CONTACT WITH ENVIRONMENTAL SITES AND THEN INOCULATION OF MOUTH

Donskey CJ. Am J Infect Control 2013;41:S12

Disinfectant Product SubstitutionsDonskey CJ. AJIC. May 2013

Improve Effectiveness of Cleaning/DisinfectionDonskey AJIC. May 2013

Automated Disinfection Devices Donskey CJ. AJIC. May 2013

Does Improving Surface Cleaning and Disinfection Reduce Healthcare-Associated Infections?

Donskey CJ. AJIC. 2013;41:S12-S19

“As reviewed here, during the past decade a growing body of evidence has accumulated suggesting that improvements in environmental disinfection may prevent transmission of pathogens and reduce HAIs. Although, the quality of much of the evidence remains suboptimal, a number of high-quality investigations now support environmental disinfection as a control strategy”

Efficacy of Disinfection Influencing Factors

Rutala, Weber, HIPAC. www.cdc.gov. 2008

• Organic load present-interfere by protect microbe from exposure or alters the disinfectant making it less antimicrobial

• Type of microbial contamination-intrinsic resistance varies

• Level of microbial contamination-larger the number of microorganisms, the more time needed to inactivate them

• Concentration of disinfectant-the more concentrated the disinfectant, the greater its efficacy and the shorter the time to achieve kill. Use manufacturer’s recommended use-dilution.

Efficacy of Disinfection Influencing Factors

• Temperature-activity increases as temperature increases

• pH-increase in pH improves the antimicrobial activity of some disinfectants (e.g., Quat) but decreases the activity of others (e.g., hypochlorites)

• Duration of exposure-must be exposed to disinfectant for kill time

• Water hardness-high concentrations can reduce the rate of kill because cations in water interact with disinfectant to form insoluble precipitates

PROPERTIES OF AN IDEAL DISINFECTANT Rutala and Weber. Infect Control Hosp Epidemiol. In press

• Broad spectrum-wide antimicrobial spectrum

• Fast acting-should produce a rapid kill

• Remains Wet-meet listed kill/contact times with a single application

• Not affected by environmental factors-active in the presence of organic matter

• Nontoxic-not irritating to user

• Surface compatibility-should not corrode instruments and metallic surfaces

• Persistence-should have sustained antimicrobial activity

• Easy to use

• Acceptable odor

• Economical-cost should not be prohibitively high

• Soluble (in water) and stable (in concentrate and use dilution)

• Cleaner (good cleaning properties) and nonflammable

LOW-LEVEL DISINFECTION FOR NONCRITICAL EQUIPMENT AND SURFACES

Exposure time > 1 minGermicide Use Concentration

Ethyl or isopropyl alcohol 70-90%Chlorine 100ppm (1:500 dilution)Phenolic UDIodophor UDQuaternary ammonium UDImproved hydrogen peroxide 0.5%, 1.4%____________________________________________________UD=Manufacturer’s recommended use dilution

Quaternary ammonium compounds (e.g., didecyl dimethyl ammonium bromide, dioctyl dimethyl ammonium bromide)

Rutala, Weber. Am J Infect Control 2013;41:S36-S41

Advantages Bactericidal, fungicidal, virucidal

against enveloped viruses (e.g., HIV) Good cleaning agents EPA registered Surface compatible Persistent antimicrobial activity when

undisturbed Inexpensive (in dilutable form) Not flammable

Disadvantages Not sporicidal In general, not tuberculocidal and

virucidal against non-enveloped viruses High water hardness and cotton/gauze

can make less microbicidal A few reports documented asthma as

result of exposure to benzalkonium chloride

Affected by organic matter Multiple outbreaks ascribed to

contaminated benzalkonium chloride

Sodium HypochloriteRutala, Weber. Am J Infect Control 2013;41:S36-S41

Advantages Bactericidal, tuberculocidal, fungicidal,

virucidal Sporicidal Fast acting Inexpensive (in dilutable form) Not flammable Unaffected by water hardness Reduces biofilms on surfaces Relatively stable (e.g., 50% reduction in

chlorine concentration in 30 days) Used as the disinfectant in water treatment EPA registered

Disadvantages Reaction hazard with acids and ammonias Leaves salt residue Corrosive to metals (some ready-to-use products

may be formulated with corrosion inhibitors) Unstable active (some ready-to-use products may

be formulated with stabilizers to achieve longer shelf life)

Affected by organic matter Discolors/stains fabrics Potential hazard is production of trihalomethane Odor (some ready-to-use products may be

formulated with odor inhibitors). Irritating at high concentrations.

Improved Hydrogen PeroxideRutala, Weber. Am J Infect Control 2013;41:S36-S41

Advantages Bactericidal, tuberculocidal, fungicidal,

virucidal Fast efficacy Easy compliance with wet-contact times Safe for workers (lowest EPA toxicity

category, IV) Benign for the environment Surface compatible Non-staining EPA registered Not flammable

Disadvantages More expensive than most other

disinfecting actives Not sporicidal at low

concentrations

AlcoholRutala, Weber. Am J Infect Control 2013;41:S36-S41

Advantages

Bactericidal, tuberculocidal, fungicidal, virucidal

Fast acting Non-corrosive Non-staining Used to disinfect small surfaces such

as rubber stoppers on medication vials No toxic residue

Disadvantages Not sporicidal Affected by organic matter Slow acting against non-enveloped viruses (e.g.,

norovirus) No detergent or cleaning properties Not EPA registered Damage some instruments (e.g., harden rubber,

deteriorate glue) Flammable (large amounts require special storage) Evaporates rapidly making contact time compliance

difficult Not recommended for use on large surfaces Outbreaks ascribed to contaminated alcohol

PhenolicsRutala, Weber. Am J Infect Control 2013;41:S36-S41

Advantages Bactericidal, tuberculocidal,

fungicidal, virucidal Inexpensive (in dilutable form) Non-staining Not flammable EPA registered

Disadvantages Not sporicidal Absorbed by porous materials

and irritate tissue Depigmentation of skin caused

by certain phenolics Hyperbilirubinemia in infants

when phenolic not prepared as recommended

Most Prevalent Pathogens Causing Healthcare-Associated Infections

Rutala, Weber. Infect Control Hosp Epidemiol. In press

Staphylococcus aureus (15.6%) E coli (11.5%) Coagulase-negative Staphylococcus (CoNS)

(11.4%) Klebsiella (8.0%) Pseudomonas aeruginosa (7.5%) Enterococcus faecalis (6.8%) Candida albicans (5.3%) Enterobacter spp. (4.7%) Other Candida spp. (4.2%) Enterococcus faecium (4.1%) Enterococcus spp. (3.0%) Proteus spp. (2.5%) Serratia spp. (2.1%) Acinetobacter baumanii (1.8%)

Modify Disinfectant Used C. difficile spores-over the past

decade, incidence of C. difficile increasing and now most common in some hospitals

Norovirus

DECREASING ORDER OF RESISTANCE OF MICROORGANISMS TO DISINFECTANTS/STERILANTS

PrionsSpores (C. difficile)

MycobacteriaNon-Enveloped Viruses (norovirus)

FungiBacteria (MRSA, VRE, Acinetobacter)

Enveloped VirusesMost Susceptible

Most Resistant

EFFECTIVENESS OF DISINFECTANTS AGAINST MRSA AND VRE

Rutala WA, et al. Infect Control Hosp Epidemiol 2000;21:33-38.

Tuberculocidal Activity of DisinfectantsRutala et al. Am J Med 1991;91:267S

A modified AOAC tuberculocidal activity test was used to assess 14 hospital disinfectants

Effective-2% glut, 0.8%HP plus 0.06% PA, 1000ppm chlorine

Not effective-QUATs, 100ppm chlorine, and 0.13% glut not effective

C. difficile spores

DISINFECTANTS AND ANTISEPSISC. difficile spores at 20 min, Rutala et al, 2006

• No measurable activity (1 C. difficile strain, J9) CHG Phenolic 70% isopropyl alcohol 95% ethanol 3% hydrogen peroxide Disinfecting spray (65% ethanol, 0.6% QUAT) Disinfecting spray (79% ethanol, 0.1% QUAT) 0.06% QUAT; QUAT may increase sporulation capacity- Lancet

2000;356:1324 10% povidone iodine 0.5% hydrogen peroxide

DISINFECTANTS AND ANTISEPSISC. difficile spores at 10 and 20 min, Rutala et al, 2006

• ~4 log10 reduction (3 C. difficile strains including BI-9) Bleach, 1:10, ~6,000 ppm chlorine (but not 1:50) Chlorine, ~19,100 ppm chlorine Chlorine, ~25,000 ppm chlorine 0.35% peracetic acid 2.4% glutaraldehyde OPA, 0.55% OPA 2.65% glutaraldehyde 3.4% glutaraldehyde and 26% alcohol

Product + Practice

ALL “TOUCHABLE” (HAND CONTACT) SURFACES SHOULD BE WIPED WITH DISINFECTANT

“High touch” objects only recently defined (no significant differences in microbial contamination of different surfaces) and

“high risk” objects not epidemiologically defined.

MICROBIAL BURDEN ON ROOM SURFACES AS A FUNCTION OF FREQUENCY OF TOUCHING

Surface Prior to CleaningMean CFU/RODAC (95% CI)

Post Cleaning (mean)Mean CFU/RODAC (95% CI)

High 71.9 (46.5-97.3) 9.6

Medium 44.2 (28.1-60.2) 9.3

Low 56.7 (34.2-79.2) 5.7

The level of microbial contamination of room surfaces is similar regardless of how often they are touched both before and after cleaning

Therefore, all surfaces that are touched must be cleaned and disinfected

Huslage K, Rutala WA, Weber DJ. ICHE. 2013;34:211-212

Surface Disinfection

• Wipe all “touchable” or “hand contact” surfaces with sufficient wetness to achieve the disinfectant contact time (> 1 minute). • Daily disinfection of surfaces (vs cleaned when soiled)

in rooms of patients with CDI and MRSA reduced acquisition of pathogens on hands after contact with surfaces and on hands caring for the patient

Key Considerations for Selecting the Optimal Disinfectant for Your Facility

Rutala, Weber. Infect Control Hosp Epidemiol. In press

Consideration Question to Ask Score (1-10)

Kill Claims Does the product kill the most prevalent healthcare pathogens

Kill Times and Wet-Contact Times

How quickly does the product kill the prevalent healthcare pathogens

Safety Does the product have an acceptable toxicity rating, flammability rating

Ease-of-Use Odor acceptable, shelf-life, in convenient forms (wipes, spray), water soluble, works in organic matter, one-step (cleans/disinfects)

Other factors Supplier offer comprehensive training/education, 24-7 customer support, overall cost acceptable (product capabilities, cost per compliant use, help standardize disinfectants in facility

Disinfectants

• Disinfectants are recommended for noncritical patient care objects (CDC, 2008)• Disinfectants are recommended for Precaution/Isolation

patients (CDC, 2007)• Disinfectants are recommended for blood/OPIM (OSHA,

1991)• Disinfectants (or detergents) are recommended for other

noncritical environmental surfaces (CDC, 2002 and 2008)

DISINFECTION OF NONCRITICAL PATIENT-CARE DEVICESRutala, Weber, HICPAC. 2008 www.cdc.gov

• Disinfect noncritical medical devices (e.g., blood pressure cuff) with an EPA-registered hospital disinfectant using the label’s safety precautions and use directions. Most EPA-registered hospital disinfectants have a label contact time of 10 minutes but multiple scientific studies have demonstrated the efficacy of hospital disinfectants against pathogens with a contact time of at least 1 minute. By law, the user must follow all applicable label instructions on EPA-registered products. If the user selects exposure conditions that differ from those on the EPA-registered product label, the user assumes liability for any injuries resulting from the off-label use and is potentially subject to enforcement action under FIFRA. (II, IC)

CLEANING AND DISINFECTING ENVIRONMENTAL SURFACES

Cleaning (removes soil) and disinfecting is one-step with disinfectant-detergent. A one-step product

achieved EPA claim in presence of soil. No pre-cleaning necessary unless spill or gross

contamination.

Justification for Using a Disinfectant for Non-Critical Surfaces/Patient Equipment• Disinfectants have antimicrobial activity and detergents do not• Surfaces may contribute to transmission of epidemiologically-important

pathogens such as MRSA, VRE, C. difficile, MDR-Acinetobacter

• Disinfectants prevent HAIs• Disinfectants are more effective than detergents in reducing

contamination on surfaces• Detergents become contaminated and result in seeding the patient’s

environment with bacteria• Disinfection of non-critical patient care items and equipment is

recommended for patients on isolation

Justification for Using a Disinfectant for Non-Critical Surfaces/Patient Equipment• Disinfectants may have antimicrobial activity and detergents do not• Surfaces may contribute to transmission of epidemiologically-important

pathogens such as MRSA, VRE, C. difficile, MDR-Acinetobacter

• Disinfectants prevent HAIs• Disinfectants are more effective than detergents in reducing



recommended for patients on isolation

Donskey CJ. Am J Infect Control 2013;41:S12

Surface DisinfectionEffectiveness of Different Methods

Rutala, Gergen, Weber. 2013, Unpublished Results

Technique (with cotton) MRSA Log10 Reduction (QUAT)

Saturated cloth 4.41

Spray (10s) and wipe 4.41

Spray, wipe, spray (1m), wipe 4.41

Spray 4.41

Spray, wipe, spray (until dry) 4.41

Disposable wipe with QUAT 4.55

Control: detergent 2.88

Transfer of C. difficile Spores by Nonsporicidal Wipes

Cadnum et al. ICHE 2013;34:441-2

• Detergent/nonsporicidal wipes transfer or spread microbes/spores to adjacent surfaces; disinfectants inactivate microbes

Justification for Using a Disinfectant for Non-Critical Surfaces/Patient Equipment• Surfaces may contribute to transmission of epidemiologically-important

pathogens such as MRSA, VRE, C. difficile, MDR-Acinetobacter, others• Disinfectants prevent HAIs• Disinfectants are more effective than detergents in reducing



recommended for patients on isolation• Disinfectants may have persistent antimicrobial activity

Bacterial Contamination of Water With and Without a Disinfectant

• Detergent become contaminated and result in seeding the patient’s environment with HA pathogens. Ayliffe et al. Brit Med J. 1966;2:442-5





recommended for patients on isolation-CDC 2007 and OSHA 1991• Disinfectants may have persistent antimicrobial activity

QUATS AS SURFACE DISINFECTANTSWITH PERSISTENT ACTIVITY

Study of computer keyboards: Challenge with VRE or P. aeruginosa

Keys wiped with alcohol or quats (CaviWipes, Clorox Disinfecting Wipes, or Sani-Cloth Plus)

Persistent activity when not removed

Rutala WA, White MS, Gergen MF,Weber DJ. ICHE 2006;27:372-77.





recommended for patients on isolation• Disinfectants may have persistent antimicrobial activity


Detergents No measurable antimicrobial activity Contaminated surfaces provide an important source of HA pathogens Similar cost (~$0.20/use gallon) Disinfectants are cause of skin, respiratory irritation or allergy No evidence that using disinfectants selects for antibiotic-resistant

bacteria Disinfectants should be used where there are scientific studies

demonstrating benefit Employ disinfectant on noncritical surfaces for all hospitalized

patients as unsuspected colonization is a routine occurrence

How About “Green” Products?

• Today, the definition of green is unregulated• It can mean:

Sustainable resources/plant-based ingredients Free of petrochemicals Biodegradable No animal testing Minimal carbon footprint Traded fairly

• It can, but does not always mean “safer”

Efficacy of “Green” Products to Inactivate MDR Pathogens

Rutala, Gergen, Weber. Unpublished results. 2013

• No measurable activity against A. baumannii, A. xyloxidans, Burkholderia cenocepacia, K. pneumoniae, MRSA and P. aeruginosa, VRE, Stenotrophomonas maltophilia

It appears that not only is disinfectant use important but how often is important

Daily disinfection vs clean when soiled

Daily Disinfection of High-Touch SurfacesKundrapu et al. ICHE 2012;33:1039

Daily disinfection of high-touch surfaces (vs cleaned when soiled) with sporicidal disinfectant (PA) in rooms of patients with CDI and MRSA reduced acquisition of pathogens on hands after contact with surfaces and of hands caring for the patient

Kill Claims for Most Prevalent Pathogens

• Each disinfectant requires a specific time it must remain in contact with the microbe to achieve disinfection-kill time or contact time• Some disinfectants may have a kill time for bacteria of 1m, which

means bacteria in label disinfected in 1m• Other products, often concentrated formulas require dilution, are

registered by the EPA with contact time of 10m• Such a long contact time is not practical

CONTACT TIMES FOR SURFACE DISINFECTION

• Follow the EPA-registered contact times, ideally Some products have achievable contact times for

bacteria/viruses (30 seconds-2 minutes) Other products have non-achievable contact times

• If use a product with non-achievable contact time Use >1 minute based on CDC guideline and scientific literature Prepare a risk assessment

http://www.unc.edu/depts/spice/dis/SurfDisRiskAssess2011.pdf

IMPROVED HYDROGEN PEROXIDE (HP) SURFACE DISINFECTANT

• Advantages 30 sec -1 min bactericidal and virucidal claim (fastest non-bleach contact

time) 5 min mycobactericidal claim Safe for workers (lowest EPA toxicity category, IV) Benign for the environment; noncorrosive; surface compatible One step cleaner-disinfectant No harsh chemical odor EPA registered (0.5% RTU, 1.4% RTU, wet wipe)

• Disadvantages More expensive than QUAT

BACTERICIDAL ACTIVITY OF DISINFECTANTS (log10 reduction) WITH A CONTACT TIME OF 1m WITH/WITHOUT FCS.

Rutala et al. ICHE. 2012; 33:1159-61

Organism Oxivir-0.5% 0.5% HP Clorox HC HP Cleaner-Dis 1.4%

1.4% HP 3.0% HP QUAT

MRSA >6.6 <4.0 >6.5 <4.0 <4.0 5.5

VRE >6.3 <3.6 >6.1 <3.6 <3.6 4.6

MDR-Ab >6.8 <4.3 >6.7 <4.3 <4.3 >6.8

MRSA, FCS >6.7 NT >6.7 NT <4.2 <4.2

VRE, FCS >6.3 NT >6.3 NT <3.8 <3.8

MDR-Ab, FCS

>6.6 NT >6.6 NT <4.1 >6.6

Improved hydrogen peroxide is significantly superior to standard HP at same concentration and superior or similar to the QUAT tested

• MRSA, VRE, C. difficile, MDR-Acinetobacter comprise a growing reservoir of epidemiologically important pathogens that have an environmental mode of transmission

• Contaminated surface environment in hospital rooms is important in transmission of HA pathogens

• Appropriate use of disinfectants prevent transmission of pathogens and reduce HAIs

• All touchable surfaces should be wiped with disinfectant• Detergents alone do not kill pathogens and can cross-contaminate the

environment


Summary

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efficacy, selection and use of disinfectants and detergents in environmental cleaning/disinfection...

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