William A. Rutala, PhD, MPH

Efficacy, Selection and Use of Disinfectants and Detergents in Environmental Cleaning/Disinfection
William A. Rutala, PhD, MPH Director, 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 STERILIZATION Rutala, 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 HAIs Weber, Rutala, Miller et al
ENVIRONMENTAL CONTAMINATION LEADS TO HAIs Weber, 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 ENDEMIC AND EPIDEMIC MRSA
Dancer SJ et al. Lancet ID 2008;8(2):101-13

ENVIRONMENTAL SURVIVAL OF KEY PATHOGENS ON HOSPITAL SURFACES
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: and Kramer 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:

RELATIVE RISK OF PATHOGEN ACQUISITION IF PRIOR ROOM OCCUPANT INFECTED
* Prior room occupant infected, 120% increased risk; ^Any room occupant in prior 2 weeks infected. Otter , Yezli, French. ICHE. 2012;32:

EVALUATION OF HOSPITAL ROOM ASSIGNMENT AND ACQUISITION OF CDI
Study design: Retrospective cohort analysis, 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:

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 Substitutions Donskey CJ. AJIC. May 2013

Improve Effectiveness of Cleaning/Disinfection Donskey 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
Efficacy of Disinfection Influencing Factors Rutala, Weber, HIPAC 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
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 min Germicide Use Concentration Ethyl or isopropyl alcohol 70-90% Chlorine 100ppm (1:500 dilution) Phenolic UD Iodophor UD Quaternary ammonium UD Improved hydrogen peroxide 0.5%, 1.4% ____________________________________________________ UD=Manufacturer’s recommended use dilution

Quaternary ammonium compounds (e. g
Quaternary ammonium compounds (e.g., didecyl dimethyl ammonium bromide, dioctyl dimethyl ammonium bromide) Rutala, Weber. Am J Infect Control 2013;41:S36-S41 Advantages Disadvantages 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 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 Hypochlorite Rutala, Weber. Am J Infect Control 2013;41:S36-S41
Advantages Disadvantages 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 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 Peroxide Rutala, Weber
Improved Hydrogen Peroxide Rutala, Weber. Am J Infect Control 2013;41:S36-S41 Advantages Disadvantages 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 More expensive than most other disinfecting actives Not sporicidal at low concentrations

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

Phenolics Rutala, Weber. Am J Infect Control 2013;41:S36-S41
Advantages Disadvantages Bactericidal, tuberculocidal, fungicidal, virucidal Inexpensive (in dilutable form) Non-staining Not flammable EPA registered 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

Non-Enveloped Viruses (norovirus) Fungi
DECREASING ORDER OF RESISTANCE OF MICROORGANISMS TO DISINFECTANTS/STERILANTS Prions Spores (C. difficile) Mycobacteria Non-Enveloped Viruses (norovirus) Fungi Bacteria (MRSA, VRE, Acinetobacter) Enveloped Viruses Most Resistant Most Susceptible

EFFECTIVENESS OF DISINFECTANTS AGAINST MRSA AND VRE
Rutala WA, et al. Infect Control Hosp Epidemiol 2000;21:33-38.

Tuberculocidal Activity of Disinfectants Rutala et al
Tuberculocidal Activity of Disinfectants Rutala 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 ANTISEPSIS C
DISINFECTANTS AND ANTISEPSIS C. 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 ANTISEPSIS C
DISINFECTANTS AND ANTISEPSIS C. 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
Prior to Cleaning Mean CFU/RODAC (95% CI) Post Cleaning (mean) High 71.9 ( ) 9.6 Medium 44.2 ( ) 9.3 Low 56.7 ( ) 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 ;34:

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 DEVICES Rutala, Weber, HICPAC
DISINFECTION OF NONCRITICAL PATIENT-CARE DEVICES Rutala, Weber, HICPAC 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

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 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

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

Surface Disinfection Effectiveness of Different Methods Rutala, Gergen, Weber. 2013, Unpublished Results Technique (with cotton) MRSA Log10 Reduction (QUAT) Saturated cloth 4.41 Spray (10s) and wipe Spray, wipe, spray (1m), wipe Spray Spray, wipe, spray (until dry) Disposable wipe with QUAT 4.55 Control: detergent 2.88

Transfer of C. difficile Spores by Nonsporicidal Wipes Cadnum et al
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

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 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 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

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 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-CDC 2007 and OSHA 1991 Disinfectants may have persistent antimicrobial activity

QUATS AS SURFACE DISINFECTANTS WITH 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:

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 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 Disinfectants may have persistent antimicrobial activity

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

Daily disinfection vs clean when soiled
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 Surfaces Kundrapu et al
Daily Disinfection of High-Touch Surfaces Kundrapu 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

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: Improved hydrogen peroxide is significantly superior to standard HP at same concentration and superior or similar to the QUAT tested 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 5.5 VRE >6.3 <3.6 >6.1 4.6 MDR-Ab >6.8 <4.3 >6.7 MRSA, FCS NT <4.2 VRE, FCS <3.8 MDR-Ab, FCS <4.1

Summary 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

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William A. Rutala, PhD, MPH

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