New Technologies for Disinfection of Environmental Surfaces John M. - - PowerPoint PPT Presentation

New Technologies for Disinfection

• f Environmental Surfaces

John M. Boyce, MD J.M. Boyce Consulting, LLC Middletown, CT

www.jmboyceconsulting.com

Disclosures: JMB is a consultant to, and has received travel support from, Diversey and GOJO Industries, and has received an honorarium from Sodexo

Burden of Healthcare-Associated Infections Due to Antimicrobial-Resistant Organisms

• 10% to 15% of all hospital patients and 65% of all nursing

home residents are colonized with one or more multidrug- resistant organisms (MDROs)

• Antibiotic-resistant organisms are responsible for:
• More than 2 million healthcare-associated infections

(HAIs), and 23,000 deaths per year in the United States

• At a direct cost of $20 billion
• More than 220,000 HAIs occur in Canada annually and

result in 8,500 - 12,000 deaths

Manning ML et al. Am J Infect Control 2018;46:364

Role of Environment in Transmission of Healthcare-Associated Pathogens

• Increasing evidence that contaminated environmental surfaces

contribute to transmission of healthcare-associated pathogens

• Contaminated surfaces serve as a source of:
• Contamination of the hands of healthcare personnel (HCP)
• Transmission to patients via direct contact
• There is substantial evidence that improving environmental

disinfection reduces transmission of pathogens

• Novel strategies for improving daily and terminal disinfection of

environmental surfaces warrant further evaluation

Hayden MK et al. Infect Control Hosp Epidemiol 2008;29:149 Otter JA et al. Infect Control Hosp Epidemiol 2011;32:687 Weber DJ et al. Curr Opin Infect Dis 2013;26:338 Donskey CJ Am J Infect Control 2013;41:S12 Boyce JM Antimicrob Resist Infect Control 2016; doi 10.1186/s13756-016-0111-x PIDAC Best Practices for Environmental Cleaning, 2018

Daily Cleaning/Disinfection Practices Are Often Suboptimal

• Patients colonized or infected with

pathogens shed the organisms onto environmental surfaces

• Daily cleaning of surfaces by

Environmental Services (EVS) staff can vary considerably, and is sometimes suboptimal

• Poor daily disinfection practices or use
• f an ineffective agent results in

persistent contamination of surfaces

Overbed Table Overbed Table Before Cleaning After Cleaning VRE on call button after cleaning

Hayden MK et al. Clin Infect Dis 2006;42:1552 Eckstein BC et al. BMC Infect Dis 2007;7:61 Faires MC et al. BMC Infect Dis 2012;12:290 Boyce JM et al. Infect Control Hosp Epidemiol 2010;31:99 Gavalda L et al. Am J Infect Control 2015;43:776

Importance of Daily Room Cleaning and Disinfection

• Appropriate daily cleaning reduces:
• Level of environmental contamination by pathogens
• Transfer of pathogens from surfaces to hands of healthcare personnel

(HCP)

• Acquisition of pathogens by patients
• HAIs

5

Hayden MK et al. Clin Infect Dis 2006;42:1552 Hardy KJ et al. J Hosp Infect 2007;66:360 Meakin NS et al. J Hosp Infect 2012;80:122 Eckstein BC et al. BMC Infect Dis 2007;7:61 Kundrapu S et al. Infect Control Hosp Epidemiol 2012;33:1039 Donskey CJ Am J Infect Control 2013;41:S12 Boyce JM et al. Am J Infect Control 2017;45:1006

Need for Innovative Approaches to Daily Disinfection of Surfaces

• High-touch surfaces become re-contaminated with pathogens

within hours after daily cleaning

• Cleaning high-touch surfaces more than once/day can reduce

both microbial burden on surfaces and HAIs

• Novel approaches for disinfecting patient rooms more

frequently than once/day are needed

Hardy KJ et al. J Hosp Infect 2007;66:360 Aldeyab MA et al. Infect Control Hosp Epidemiol 2009;30:304 Wilson AP et al. Crit Care Med 2011; Attaway HH et al. Am J Infect Control 2012;40:907 Bogusz A et al. Healthcare Infect 2013;18:3 Schmidt MG et al. Infect Control Hosp Epidemiol 2013;34:530 Dancer SJ et al. BMC Med 2009;7:28

Importance of Terminal Room Cleaning/Disinfection

• Multiple studies have assessed terminal room disinfection by
• btaining cultures Before and After terminal room

cleaning/disinfection

• Quality of both daily and terminal cleaning is highly variable, and is
• ften suboptimal
• Residual contamination of surfaces occurs if terminal disinfection is

not performed correctly

7

Otter JA et al. J Hosp Infect 2007;67:182 Hota B et al. J Hosp Infect 2009;71:123 Otter JA et al. Am J Infect Control 2010;38:754 Carling PC et al. Infect Control Hosp Epidemiol 2008;29:1035 Boyce JM et al. Infect Control Hosp Epidemiol 2011;32:1187 Manian FA Am J Infect Control 2013;41:384 Sitzlar B et al. Infect Control Hosp Epidemiol 2013;34:459 Rupp ME et al. Infect Control Hosp Epidemiol 2014;35:721 Ali S et al. J Hosp Infect 2016;93:70

Level of MDRO Surfaces Contamination After Manual Terminal Cleaning, BETR study

N = 80 CFU (~ 3 CFU/cm2)

Chen LF et al. Infect Control Hosp Epidemiol 2019;40:47

Baseline Contamination of Hospital Surfaces at Enrollment by Pathogen

• Prospective study of surface contamination

and MDRO transmission events

• Rooms vacated by patients on Contact Precautions

cultured when new patients were admitted

• > 1 MDRO was recovered from 55% of rooms

after manual terminal cleaning

Risk Associated with Prior Room Occupancy

• Patients admitted to a

room previously

• ccupied by a patient

with a resistant pathogen are at increased risk of acquiring the organism

• On average, they are

twice as likely to acquire the pathogen as patients admitted to a room not

• ccupied by a patient

with a resistant pathogen

Risk of Acquisition of pathogens from Prior Room Occupants

Mitchell DB et al. J Hosp Infect 2015;91:211

Rationale for Adopting New Technologies to Supplement Manual Disinfection Practices

• Continuing challenges affecting effectiveness of

environmental disinfection programs:

• Frequent personnel turnover in EVS departments
• Low salaries available for EVS personnel
• Inadequate training of EVS and nursing personnel
• Confusion among EVS and nursing personnel regarding “who is

supposed to clean what?”

• New strategies for cleaning/disinfecting environmental

surfaces are needed

• “No-touch” methods designed to supplement manual

disinfection are gaining popularity, but choosing the most appropriate technology can be difficult

Zuberi DM et al. Soc Sci Med 2011;72:907 Dumigan DG et al. Am J Infect Control 2010;38:387 Anderson RE et al. J Hosp Infect 2011;78:178

No-Touch Disinfection Technologies

• Hydrogen peroxide vapor (HPV)
• Aerosolized hydrogen peroxide
• HPV + peracetic acid
• Ozone gas
• Quaternary ammonium fogging
• Alcohol mist
• Steam vapor
• Aerosolized peracetic acid/H2O2
• Ultraviolet light
• Mobile devices
• Fixed installations
• Self-disinfecting surfaces
• Copper alloys
• Silver
• Organosilane surface applications
• High- intensity, narrow spectrum

light (405 nm)

• UV-based air disinfection systems

Doll M et al. Curr Infect Dis Rep 2015;17:44 Weber DJ et al. Am J Infect Control 2016;44(5 Suppl):e77 Weber DJ et al. Curr Opin Infect Dis 2016;29:424 Marra AR et al. Infect Control Hosp Epidemiol 2018;39:20 PIDAC Best Practices for Environmental Cleaning, 3rd ed., 2018

Hydrogen Peroxide Vapor Micro-Condensation Process

• Hydrogen peroxide vapor (HPV) micro-condensation

process

• Uses 30% - 35% H2O2
• Produces vapor [gas] (particle size < 1 u)
• H2O2 is distributed throughout room being treated
• H2O2 converted to water and oxygen (no residue)
• Effective against a broad range of healthcare-

associated pathogens including C. difficile spores

• Yields 105 to 106 log10 reduction of most pathogens
• Air ducts and doors must be closed during process,

which takes 2-3 hours

Generator Aeration unit Otter JA et al. J Hosp Infect 2011;83:1 Weber DJ et al. Am J Infect Control 2016;44(5 Suppl):e77 Marra AR et al. Infect Control Hosp Epidemiol 2018;39:20 PIDAC Best Practices for Environmental Cleaning, 2018

Hydrogen Peroxide Vapor

• Multiple studies have shown that HPV reduces bacterial

contamination of surfaces in outbreak and non-outbreak settings

• Impact of HPV on MDRO acquisition or infection
• 5 studies in outbreak settings
• 4 studies in non-outbreak settings
• All studies showed reduction of HAIs due to target pathogens
• Regression to the mean may have explained some reductions
• Due to room turn-around times, HPV is not practical for

routine terminal room disinfection

• Most likely to be helpful for:
• Terminating outbreaks or transmission in hyperendemic settings
• Reducing difficult-to-eradicate or highly dangerous pathogens

Weber DJ et al. Am J Infect Control 2016;44(5 Suppl):e77 Marra AR et al. Infect Control Hosp Epidemiol 2018;39:20 PIDAC Best Practices for Environmental Cleaning, 2018

Hydrogen Peroxide “Dry” Mist Systems

• One system uses 5% H2O2, <50 ppm silver and <50 ppm
• rthophosporic acid
• Inactivated < 10% of pouched 106 G. stearothermophilus spores

(BIs)

• ~33% of 104 G. stearothermophilus spores
• Uneven distribution within room
• Has shown reduction in bacterial contamination in experimental

and actual hospital rooms

• Eliminated growth of bacteria and mold from surfaces in 5 rooms
• f a burn unit
• Clinical isolates and reference strains inoculated on glass carriers

3 – 4.6 log10 reductions of various pathogens were achieved

• Less effective than HPV vs C. difficile spores

Andersen BM et al. J Hosp Infect 2006;62:149 Bartels MD et al. J Hosp Infect 2008;70:35 Shapey S et al. J Hosp Infect 2008;70:136 Fu TY et al. J Hosp Infect 2012:80:199 Cobrado L et al. Surg Infect 2018;19: doi 10.1089/sur.2017.311 Herruzo R J Hosp Infect 2014;87:175

Hydrogen Peroxide “Dry” Mist Systems

• Another system uses 6% - 12 % H2O2 and creates a fog
• One study compared the system to detergent cleaner
• Percent of rooms yielding MRSA after use of detergent

vs H2O2 was 24.7% vs 18.8% (p < .001)

• Significant reduction occurred at only one site (bed)
• Significant reduction in MRSA acquisition and infection
• Multiple confounding variables were present
• Another study found only ~1.0 – 1.7 log10 reductions of

VRE

• No convincing data regarding impact on HAIs for

either “dry mist” system

Mitchell BG et al. BMJ Open 2014;4:e004522 Chan HT et al. J Hosp Infect 2011;79:125

UVC Light Room Decontamination Systems

• Automated mobile UV light units that emit UVC (254 nm range) are available

in a variety of sizes, designs and acquisition & maintenance costs

• Some units have built-in sensors; some provide separate sensors
• Some have software for tracking usage

1,00E-05 1,00E-04 1,00E-03 4 ft Direct 4 ft Zero Angle 10 ft Direct 10 ft Zero Angle Shaded 4 ft Shaded 10 ft

Mean UVC Irradiance (W/cm2)

Cadnum JL et al. Infect Control Hosp Epidemiol 2016;37:555 Boyce JM et al. Infect Control Hosp Epidemiol 2016;37:667

Parameters Effecting UVC Effectiveness

• UV-C irradiance and antimicrobial efficacy are effected by test methods
• Method of preparing inoculum of test pathogens
• Area over which the inoculum is spread on test surfaces
• Distance and orientation of test surfaces relative to the UVC device
• Types of organic load used in tests

Impact of Distance from UVC Device and Angle of UV Light on Log10 Reductions Achieved

0,5 1 1,5 2 2,5 3 3,5 4 4,5 5

1.3 m, direct 1.3 m, 0 °angle 1.3 m, shaded 3.3 m, direct 3.3 m, 0° angle 3.3 m, shaded

Mean Log10 Reduction MRSA

• C. difficile

Data source: Boyce JM et al. Infect Control Hosp Epidemiol 2016;37:667-672

Comparison of Two UVC Devices

• Devices were tested for log10 reductions

against

• MRSA, C. difficile, VRE
• Results:
• Both devices yielded similar reductions at

4 ft from devices with 41-min cycles

• VRE - 5 log10 reductions
• MRSA - 4 log10 reductions
• C. difficile - ~ 3 log10 reductions
• Efficacy was decreased with
• Presence of organic load
• Increasing distance from device
• Location in shaded area (indirect light)
• UVC dose delivered

Nerandzic MM PLoS One 2014;9:e107444

Comparison of two UVC Devices

• Efficacy of 2 UVC devices were compared
• 360 surfaces in rooms of patients with MRSA, VRE or C. difficile
• Stainless steel carrier inoculated with MRSA and VRE
• Percent of surfaces contaminated
• After manual cleaning:
• MRSA – 27.9%, VRE – 29.5%, C. difficile – 22.7%
• After UVC disinfection
• MRSA – 3.3%, VRE – 4.9%, C. difficile – 0%
• Odds of detecting growth on carriers was 7 times higher for

1 machine for a given organism, surface and concentration

• Conclusions:
• UVC devices are effective, but vary in the ability to reduce high

concentrations of organisms in the presence of organic material

• Set-up times and cycle times vary considerably; may affect choice

Wong T et al. Am J Infect Control 2016;44:416

Comparison of UVC and Pulsed Xenon Devices

• A study compared UVC and pulsed xenon (PX-UV) devices

effectiveness against C. difficile, MRSA and VRE

• 10-min cycles were run, with slides at 4 ft from device
• Impact of distance from device, organic load and indirect light were

evaluated

• Outcomes:
• Reduction of pathogens on glass slides
• Reduction of bacteria on hospital surfaces
• Results:
• Log10 reductions on glass slides achieved with PX-UV

VRE – 0.6; MRSA – 1.85; C. difficile – 0.55

• Efficacy of PX-UV was dramatically reduced by increasing distance,

but not by organic load or indirect light

Nerandzic MM et al. Infect Control Hosp Epidemiol 2015;36:192

Comparison of UVC and Pulsed Xenon Devices

• Log10 reductions

achieved by UVC device were significantly greater than PX-UV for all 3 pathogens

• PX-UV reduced bacteria
• n clinical surfaces

Nerandzic MM et al. Infect Control Hosp Epidemiol 2015;36:192

Comparison of UV devices in Radiology Procedure Room

• Prospective study of 8 mobile UV

devices in Radiology Dept.

• 4 standard vertical towers (LPM 1-4)
• 1 pulsed xenon device
• 1 with adjustable bulbs
• Fixed position and robotic
• 1 with 3 vertical towers
• UV irradiance measured
• Reduction of pathogens on

stainless steel disks measured

• 4-minute cycle time used
• UV-C devices emitted 254 nm light;

different levels of irradiance (intensity)

• Pulsed xenon device emitted

mostly UV-A and UV-B

• Very little UVC (254 nm)

Cadnum JL et al. Infect Control Hosp Epidemiol 2019;40:158

Standard tower units Non-standard UV-C units

Comparison of UV devices in Radiology Procedure Room

• All UVC devices reduced pathogens on disks significantly

more than the pulsed xenon device (p < .0001 for all)

• Efficacy of 4 standard UVC devices (LPM 1-4) was similar
• ~ 2 log10 or greater reductions of VRE and MRSA
• ~ 1 log10 reduction of C. difficile spores
• UVC device 2 yielded significantly greater reductions than 3 and 4
• No significant difference in efficacy of non-standard devices
• Device with adjustable arms was as effective as standard

UVC vertical tower devices despite lower UVC intensity

• Adjustable bulbs were extended horizontally over test surface

Cadnum JL et al. Infect Control Hosp Epidemiol 2019;40:158

Impact of UVC Decontamination Systems

• n Healthcare-Associated Infections
• Multiple other studies have shown that UVC and PX-UV devices can

reduce bacterial contamination of surfaces

• Systematic review included 13 UV studies
• When results of studies were pooled, statistically significant reduction
• C. difficile - pRR, 0.64 VRE - pRR, 0.42
• No significant reductions in MRSA or Gram-negative incidence rates
• Health Quality Ontario reviewed 10 studies published before Feb

2017 for evidence of efficacy vs C. difficile

• 3 studies on UVC [including BETR study], 7 studies on PX-UV
• Findings were inconsistent or of very low quality (GRADE system)
• Conclusion: Unable to make firm conclusion regarding efficacy

Marra AR et al. Infect Control Hosp Epidemiol 2018;39:20 Ont Health Technol Assess Ser 2018;18:1

Impact of UVC Decontamination Systems

• n Healthcare-Associated Infections
• Secondary analysis of BETR study
• Multicenter prospective, cluster-randomized crossover trial of UVC

for terminal disinfection of hospital rooms 9 hospitals, comparing

• Standard quat disinfectant alone (reference)
• Standard quat disinfectant + UVC
• Sodium hypochlorite (bleach) alone
• Sodium hypochlorite + UVC
• Outcome measures
• Hospital-wide incidence of acquisition or infection due to MRSA, VRE or
• C. difficile
• Results
• Significant hospital-wide reduction in acquisition of C. difficile (p = 0.031)

and VRE (p = 0.48)

26

Anderson DJ et al. Lancet Infect Dis 2018;18:845

Assessing UVC Doses Achieved in Hospital Settings

Boyce JM et al. Infect Control Hosp Epidemiol 2016;37:667-672

• Current options include:
• Device with built-in sensors on device
• Device supplied with separate radiometers
• Purchase commercially-available radiometers
• Photochromic (colorimetric) indicator test strips

Fleming M et al. Am J Infect Control 2018;46:241

Implementation Issues to Consider

Issues to Address When Considering Mobile Ultraviolet Light Systems

• Duration of cycle times recommended by manufacturer
• Evidence of microbiological efficacy published by

independent investigators

• Cost per device ($40,000 - $125,000)
• Cost of replacement bulbs/service contracts
• Availability of digital recording, storage & retrieval of data
• Ease of use

– Affects the frequency of use; number of rooms disinfected

29

Issues to Address When Considering Mobile Ultraviolet Light Systems

• Spencer et al. used human factors engineering to identify factors

affecting device selection

• Room turn-around time was a deciding factor
• A pause and reposition capability was considered desirable
• Ease of maneuverability was a factor
• Use of a dedicated EVS personnel to operate the device
• Ability to monitor UV doses delivered and device utilization
• Forming a multidisciplinary team to develop a business case for

use of UV can facilitate administrative approval

• Focus group held at APIC meeting identified selection criteria
• Efficacy
• Cycle time (room turn-around time)
• Device cost
• Ease of use/portability

Spencer M et al. Am J Infect Control 2017;45:288

Comparison of HPV vs Mobile UV Light System

• Prospective study involving 15 rooms, each decontaminated once

with HPV and UV-C light processes, at intervals > 2 months

• Of sites which had (+) ACCs before decontamination

– 93% yielded no growth after HPV treatment – 52% yielded no growth after UV-C light treatment

• Mean C. difficile log reductions: > 6 logs for HPV vs ~ 2 logs for UVC
• Mean cycle times: 153 min for HPV vs 73 min for UVC
• HPV was significantly more effective in rendering surfaces culture-

negative; more effective vs spores

• UVC was faster and easier to use

Havill NL & Boyce JM ICHE 2012;33:507

31

Other Technologies for Terminal Room Disinfection

• Ultrasonic peracetic acid/hydrogen peroxide fogging
• In 1 published study, the system eliminated MRSA, C. difficile and

VRE from stainless steel disks placed in 7 patient rooms, with > 5 log10 reductions

• Several hospitals using the system monitored air for hydrogen

peroxide and acetic acid at time of implementation

• Total setup and operation time was ~ 1 hr
• Another laboratory based study showed significant reduction of

spores

• No published data regarding impact on HAI rates

Mana TSC et al. Am J Infect Control 2017;45:327 Wood JP et al. J Hazardous Materials 2013;250:61

Other Technologies for Terminal Room Disinfection

• Gaseous ozone has been proposed as a method
• f room decontamination, but few clinical

studies are available

• Sharma M Am J Infect Control 200836:559
• Moat J et al. Can J Microbiol 2009;55:928
• Alcohol/quaternary ammonium fogging system

was shown to be less effective than bleach

• Jury LA et al. Am J Infect Control 2010;38:234
• Chlorine dioxide fogging is promoted for room

decontamination, but few published studies in hospital settings are available

• Lowe JJ et al. J Occup Environ Hyg 2013;10:533

33

Self-Disinfecting Surfaces

• Systematic review of antimicrobial surfaces revealed:
• 7 studies of copper, 1 of silver, 2 of organosilanes, 1 of metal alloy
• Copper produced a median of < 1 log10 reduction (range <1 – 2 log10)
• Two trials reported reduced HAIs in units equipped with copper alloy

surfaces or linen, but were considered to be of low quality

• Conclusion: further studies are needed to assess impact on HAIs
• Recent study employed copper-alloy coated surfaces and

copper-containing linens in a new wing of a hospital

• Reported 83% fewer C. difficile infections, fewer MDRO HAIs
• However, study had several limitations
• Other types of self-disinfecting surfaces under investigation
• Shark skin-like surfaces
• Titanium dioxide-coated surfaces

Muller MP et al. J Hosp Infect 2016;92:7 Salgado CD et al. Infect Control Hosp Epidemiol 2013;34:479 Sifri CD et al. Am J Infect Control 2016;44:1565 Querido MM et al. Colloids Surf B Biointerfaces 2019;178:8

Narrow-Spectrum High Intensity (405 nm) Light

• Narrow-spectrum high intensity

(405 nm) visible light

• Slow germicidal effect that increases with

extended exposure times

• Targets porphyrins in bacteria
• Release of intracellular reactive oxygen

species that have antimicrobial properties

• Laboratory & clinical studies have

shown reduction of bacteria on surfaces

• Blue light effective against vegetative

pathogens and C. difficile spores

• White light not effective vs C. difficile

spores

• Can be used when patients or

personnel are in room

• Data on impact on HAIs are needed

Maclean M et al. J Hosp Infect 2014;88:1 Bache SE et al. J Hosp Infect 2018;98:67 Rutala WA et al. Infect Control Hosp Epidemiol 2018;39:1250

UV-Based Air Decontamination

• Increased interest in indoor air quality
• Aerosolization of healthcare pathogens
• E.g., S. aureus, C. difficile, Acinetobacter baumannii
• Surface contamination by airborne pathogens
• Decontamination of indoor air to reduce surface contamination

and healthcare-associated infections

• Variety of technologies are under investigation
• Impact on surface contamination, pathogen transmission and HAIs not clear, and

requires further studies

Best EL et al. Clin Infect Dis 2010;50:1450 Smith J et al. J Hosp Infect 2018;100:e123 Wei J et al. Am J Infect Control 2016;44:S102 Sattar SA et al. Am J Infect Control 2016;44:e177 Guimera D et al. Am J Infect Control 2018;46:223 Zargar B et al. Lett Appl Microbiol 2019;68:206 Parvizi J et al. Am J Infect Control 2017;45:1267 Bischoff W et al. Am J Infect Control 2019 (Epub ahead of print)

Device is installed in HVAC system Shielded ceiling-mounted device

Examples of Air Decontamination Systems

Systems with UVC + Filter

Summary

• Achieving and maintaining optimal daily and terminal

disinfection of surfaces are a continuing challenge

• “No-touch” technologies designed to supplement, but not

replace, manual cleaning/disinfection have the potential to improve the quality of environmental disinfection

• Despite limitations of published studies, current evidence
• Demonstrates that novel technologies can reduce environmental

contamination

• Suggests their use can play a role in reducing HAIs
• Continued research on the impact of using “no-touch”

technologies on transmission of pathogens and reduction of HAIs is needed