Elaine L. Larson Lectureship Disinfection and Sterilization: From Benchtop to Bedside William A....

Elaine L. Larson Lectureship Disinfection and Sterilization:

From Benchtop to Bedside

William A. Rutala, Ph.D., M.P.H., C.I.C.University of North Carolina (UNC) Health Care and

UNC at Chapel Hill, NC

Disinfection and Sterilization:From Benchtop to Bedside

• Improved products/processes/technologies Low-temperature sterilization technology, rapid readout BIs,

improved HLD/LLD, wipes, microfiber

• Improved knowledge Emerging pathogens-C. difficile, Norovirus, MDROs The role of the environment in disease transmission

• Guidelines-integration of science into practice and improved patient care

DISCLOSURES• Consultation

Advanced Sterilization Products, Clorox• Honoraria (speaking)

Advanced Sterilization Products, 3M• Grants

CDC

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 but high numbers of bacterial spores

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

New Trends in Sterilization of Patient Equipment

• Alternatives to ETO-CFCETO-CO2, ETO-HCFC, 100% ETO

• New Low Temperature Sterilization TechnologyHydrogen Peroxide Gas Plasma-most commonVaporized hydrogen peroxideOzone

Rapid Readout BIs for Steam Required a 1-3h Readout Compared to 24-48h

DISINFECTION AND STERILIZATION





High-Level Disinfection of “Semicritical Objects”

Exposure Time > 8m-45m (US), 20oCGermicide Concentration_____Glutaraldehyde > 2.0%Ortho-phthalaldehyde 0.55%Hydrogen peroxide* 7.5%Hydrogen peroxide and peracetic acid* 1.0%/0.08%Hydrogen peroxide and peracetic acid* 7.5%/0.23%Hypochlorite (free chlorine)* 650-675 ppmAccelerated hydrogen peroxide 2.0%Peracetic acid 0.2%Glut and isopropanol 3.4%/26%Glut and phenol/phenate** 1.21%/1.93%___*May cause cosmetic and functional damage; **efficacy not verified

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





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 (HP) 0.5%, 1.4%____________________________________________________UD=Manufacturer’s recommended use dilution

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. In press

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

1.4% HP 3.0% HP A456-IIQUAT

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

CONTACT TIMES

• 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 minutes based on CDC guideline and scientific literature Prepare a risk assessment

Hospital Privacy Curtains(sprayed “grab area” 3x from 6-8” with IHP and allowed 2 minute contact)

Decontamination of Curtains with Improved HPRutala, Gergen, Weber. 2012

CP for: Before DisinfectionCFU/5 Rodacs (#Path)

After DisinfectionCFU/5 Rodacs (#Path)

% Reduction

MRSA 330 (10 MRSA) 21*(0 MRSA) 93.6%

MRSA 186 (24 VRE) 4* (0 VRE) 97.9%

MRSA 108 (10 VRE) 2* (0 VRE) 98.2%

VRE 75 (4 VRE) 0 (0 VRE) 100%

VRE 68 (2 MRSA) 2* (0 MRSA) 97.1%

VRE 98 (40 VRE) 1* (0 VRE) 99.0%

MRSA 618 (341 MRSA) 1* (0 MRSA) 99.8%

MRSA 55 (1 VRE) 0 (0 MRSA) 100%

MRSA, VRE 320 (0 MRSA, 0 VRE) 1* (0 MRSA, 0 VRE) 99.7%

MRSA 288 (0 MRSA) 1* (0 MRSA) 99.7%

Mean 2146/10=215 (432/10=44) 33*/10=3 (0) 98.5%

* All isolates after disinfection were Bacillus sp

WipesCotton, Disposable, Microfiber

Wipe should have sufficient wetness to achieve the disinfectant contact time. Discontinue use of the wipe if no longer leaves the surface visibly wet for > 1m

SURFACE DISINFECTIONEffectiveness of Different Methods, Rutala et al. 2012

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

MicrofiberMicrofiber demonstrated superior microbial removal compared to cotton mop with detergent; use of

disinfectant did not improve microbial elimination demonstrated by the microfiber

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

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

• ~4 log10 reduction (3 C. difficile strains including BI-9) Clorox, 1:10, ~6,000 ppm chlorine (but not 1:50) Clorox Clean-up, ~19,100 ppm chlorine Tilex, ~25,000 ppm chlorine Steris 20 sterilant, 0.35% peracetic acid Cidex, 2.4% glutaraldehyde Cidex-OPA, 0.55% OPA Wavicide, 2.65% glutaraldehyde Aldahol, 3.4% glutaraldehyde and 26% alcohol

C. difficile CONTROL MEASURESOrenstein et al. ICHE 2011;32:1137

• In units with high endemic C. difficile infection rates or in an outbreak setting, use dilute solutions of 5.25-6.15% sodium hypochlorite (e.g., 1:10 dilution of bleach) for routine disinfection. (Category II).

• We now use chlorine solution in all CDI rooms for routine daily and terminal cleaning (formerly used QUAT in patient rooms with sporadic CDI). One application of an effective product covering all surfaces to allow a sufficient wetness for > 1 minute contact time. Chlorine solution normally takes 1-3 minutes to dry.

• For semicritical equipment, glutaraldehyde (20m), OPA (12m) and peracetic acid (12m) reliably kills C. difficile spores using normal exposure times

INACTIVATION OF MURINEAND HUMAN NOROVIRUES

Disinfectant, 1 min MNV Log10 Reduction HNV Log10 Reduction

70% Ethanol >4 (3.3 at 15sec) 2

70% Isopropyl alcohol 4.2 2.2

65% Ethanol + QUAT >2 3.6

79% Ethanol + QUAT 3.4 3.6

Chlorine (5,000ppm) 4 3

Chlorine (24,000ppm) 2.4 4.3

Phenolic, QUAT, Ag, 3% H202 <1 <1 (2.1 QUAT)

0.5% Accel H202 3.9 2.8

Rutala WA, Folan MP, Tallon LA, Lyman WH, Park GW, Sobsey MD, Weber DJ. 2007

WOULD OUR QUAT KILL MRSA?Rutala et al. J Clin Microbiol. 1983;18:683

SUSCEPTIBILITY OF RESISTANT BACTERIA TO DISINFECTANTSRutala et al. ICHE 1997;18:417

No relationship between antibiotic resistance and disinfectant resistance

EFFECTIVENESS OF DISINFECTANTS AGAINST MRSA AND VRE

Antibiotic resistance does not correlate to increased resistance to disinfectants

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

ENVIRONMENTAL CONTAMINATION LEADS TO HAIs

• There is increasing evidence to support the contribution of the environment to disease transmission

• This supports comprehensive disinfecting regimens (goal is not sterilization) to reduce the risk of acquiring a pathogen from the healthcare environment

KEY PATHOGENS WHERE ENVIRONMENTIAL SURFACES PLAY A ROLE IN TRANSMISSION

• MRSA• VRE• Acinetobacter spp.• Clostridium difficile

• Norovirus• Rotavirus• SARS

Thoroughness of Environmental CleaningCarling et al. ECCMID, Milan, Italy, May 2011

0

20

40

60

80

100

%

DAILY CLEANING

TERMINAL CLEANING

Cle

an

ed

Mean = 32%

>110,000 Objects

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

• Microbial persistence in the environment In vitro studies and environmental samples MRSA, VRE, AB, CDI

• Frequent environmental contamination MRSA, VRE, AB, CDI

• HCW hand contamination MRSA, VRE, AB, CDI

• Relationship between level of environmental contamination and hand contamination CDI

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

• Person-to-person transmission Molecular link MRSA, VRE, AB, CDI

• Housing in a room previously occupied by a patient with the pathogen of interest is a risk factor for disease MRSA, VRE, CDI

• Improved surface cleaning/disinfection reduces disease incidence MRSA, VRE, CDI

C. difficile Environmental ContaminationRutala, Weber. SHEA. 3rd Edition. 2010

• Frequency of sites found contaminated~10->50% from 13 studies-stethoscopes, bed frames/rails, call buttons, sinks, hospital charts, toys, floors, windowsills, commodes, toilets, bedsheets, scales, blood pressure cuffs, phones, door handles, electronic thermometers, flow-control devices for IV catheter, feeding tube equipment, bedpan hoppers

• C. difficile spore load is low; 7 studies assessed the spore load and most found <10 colonies on surfaces found to be contaminated. Two studies reported >100; one reported a range of “1->200” and one study sampled several sites with a sponge and found 1,300 colonies C. difficile.

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

Risk of Acquiring MRSA and VREfrom Prior Room Occupants

• Admission to a room previously occupied by an MRSA-positive patient or VRE-positive patient significantly increased the odds of acquisition for MRSA and VRE (although this route is a minor contributor to overall transmission). Arch Intern Med 2006;166:1945.

• Prior environmental contamination, whether measured via environmental cultures or prior room occupancy by VRE-colonized patients, increases the risk of acquisition of VRE. Clin Infect Dis 2008;46:678.

• Prior room occupant with CDAD is a significant risk for CDAD acquisition. Shaughnessy et al. ICHE 2011;32:201

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.

Thoroughness of Environmental CleaningCarling et al. ECCMID, Milan, Italy, May 2011

0

20

40

60

80

100

%

DAILY CLEANING

TERMINAL CLEANING

Cle

an

ed

Mean = 32%

>110,000 Objects

MONITORING THE EFFECTIVENESS OF CLEANINGCooper et al. AJIC 2007;35:338

• Visual assessment-not a reliable indicator of surface cleanliness

• ATP bioluminescence-measures organic debris (each unit has own reading scale, <250-500 RLU)

• Microbiological methods-<2.5CFUs/cm2-pass; can be costly and pathogen specific

• Fluorescent marker

TERMINAL ROOM CLEANING: DEMONSTRATION OF IMPROVED CLEANING

Evaluated cleaning before and after an intervention to improve cleaning

36 US acute care hospitals Assessed cleaning using a

fluorescent dye Interventions

Increased education of environmental service workers

Feedback to environmental service workers

†Regularly change “dotted” items to prevent targeting objects

Carling PC, et al. ICHE 2008;29:1035-41

ROOM DECONTAMINATION UNITSRutala, Weber. ICHE. 2011;32:743

UV Room Decontamination• Fully automated, self calibrates, activated by hand-held remote• Room ventilation does not need to be modified• Uses UV-C (254 nm range) to decontaminate surfaces• Measures UV reflected from walls, ceilings, floors or other treated

areas and calculates the operation time to deliver the programmed lethal dose for pathogens.

• UV sensors determines and targets highly-shadowed areas to deliver measured dose of UV energy (12,000µWs/cm2 bacteria)

• After UV dose delivered, will power-down and audibly notify the operator

• Reduces colony counts of pathogens by >99.9% within 20-25m

EFFECTIVENESS OF UV ROOM DECONTAMINATION

Rutala WA, et al. Infect Control Hosp Epidemiol. 2010;31:1025-1029.

HP SYSTEMS FOR DECONTAMINATION OF THE HOSPITAL ENVIRONMENT

Falagas, et al. J Hosp Infect. 2011;78:171.

Author, Year HP System Pathogen Before HPV After HPV % Reduction

French, 2004 VHP MRSA 61/85-72% 1/85-1% 98

Bates, 2005 VHP Serratia 2/42-5% 0/24-0% 100

Jeanes, 2005 VHP MRSA 10/28-36% 0/50-0% 100

Hardy, 2007 VHP MRSA 7/29-24% 0/29-0% 100

Dryden, 2007 VHP MRSA 8/29-28% 1/29-3% 88

Otter, 2007 VHP MRSA 18/30-60% 1/30-3% 95

Boyce, 2008 VHP C. difficile 11/43-26% 0/37-0% 100

Bartels, 2008 HP dry mist MRSA 4/14-29% 0/14-0% 100

Shapey, 2008 HP dry mist C. difficile 48/203-24%; 7 7/203-3%; 0.4 88

Barbut, 2009 HP dry mist C. difficile 34/180-19% 4/180-2% 88

Otter, 2010 VHP GNR 10/21-48% 0/63-0% 100

ROOM DECONTAMINATION WITH HPV

Study design Before and after study of HPV

Outcome C. difficile incidence

Results HPV decreased environmental

contamination with C. difficile (p<0.001), rates on high incidence floors from 2.28 to 1.28 cases per 1,000 pt days (p=0.047), and throughout the hospital from 1.36 to 0.84 cases per 1,000 pt days (p=0.26)

Boyce JM, et al. Infect Control Hosp Epidemiol. 2008;29:723-729.

UV ROOM DECONTAMINATIONRutala, Weber. ICHE. 2011;32:744

HP ROOM DECONTAMINATIIONRutala, Weber. ICHE. 2011;32:743

A Four-Arm Prospective, Multicenter Study to Assess Efficacy, Effectiveness and Feasibility of Enhanced Room Disinfection with Chlorine and UV Light Using Clinical and Microbiologic Outcomes

Patient with colonization or infection due to MRSA, VRE, or

MDR-Acinetobacter

Discharge

EVS Notified

Room Disinfection

New patient admitted

4 ARMS

Surveillance for HAI

QUAT No UV Light

UV Light

No UV Light

UV Light

BLEACH

Rapid Hospital Room Decontamination Using UV Light With a Nanoscale Reflective Coating

• Assessed the time required to kill HAI pathogens in a room with standard white paint (2-5% reflective) versus walls coated with an agent formulated to be reflective to UV-C wavelengths (65% reflective)

• Coating uses nanoscale metal oxides whose crystal structures are reflective to UV-C

• Coating is white in appearance and can be applied with a brush or roller in the same way as any common interior latex paint

• Cost to coat walls used in this study was estimated to be <$300.

UV Reflective CoatingRutala, Gergen, Tande, Weber. 2012

Line-of-Sight MRSA w/coating MRSA no coating C. difficile w/coating C. difficile no coating

Cycle Time 5m03s 25m13s 9m24s 43m42s

Direct 4.70 (n=42) 4.72 (n=33) 3.28 (n=39) 3.42 (n=33)

Indirect 4.45 (n=28) 4.30 (n=27) 2.42 (n=31) 2.01 (n=27)

Total 4.60 (n=70) 4.53 (n=60) 2.91 (n=70) 2.78 (n=60)

With the nanoscale reflective coating, cycle times were 5-10m (~80% reduction) which would substantially reduce the turnover time of the room





• Guidelines/recommendations-integration of science into practice and improved patient care

Scientific Findings Incorporated Into Guidelines/Policies/Practices

• Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 (CDC)

• Multi-Society Guideline on Reprocessing Flexible Gastrointestinal Endoscopes, 2011, (ASGE, SHEA, APIC, SGNA, TJC, etc)

• Environmental Infection Control in Healthcare Facilities, 2003 (CDC)• Disinfection and Sterilization of Prion-Contaminated Medical Instruments,

2010 (SHEA)• Guideline for the Prevention and Control of Norovirus Gastroenteritis

Outbreaks in Healthcare Facilities, 2011 (CDC)• Clinical Practice Guideline for Clostridium difficile Infection in Adults, 2010

(SHEA, IDSA)

Summary New sterilization, high-level disinfection and low-level disinfection

technologies/practices/products are effective New technologies/practices/products integrated into

guidelines/policies/practices Effective surface disinfection essential to eliminate the

environment as a source for transmission of HA pathogens. Room decontamination technologies should be considered for

terminal room disinfection (e.g., after discharge of patients under CP, during outbreaks) if studies continue to demonstrate an infection reduction benefit.

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Elaine L. Larson Lectureship Disinfection and Sterilization: From Benchtop to Bedside William A....

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