Disinfectants Detergents and Microfiber Current and Future Issues

Disinfectants, Detergents and Microfiber: Current and Future Issues William A. Rutala, Ph. D, 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 n ASP (Advanced Sterilization Products), Clorox Grants n CDC, CMS

Disinfectants, Detergents and Microfiber Objective Describe emerging knowledge and controversies related to disinfectants, detergents and microfiber cleaning products

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 n CRITICAL - objects which enter normally sterile tissue or the vascular system or through which blood flows should be sterile n 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 n 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 n CRITICAL - objects which enter normally sterile tissue or the vascular system or through which blood flows should be sterile n 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 n NONCRITICAL - objects that touch only intact skin require low-level disinfection

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)

LECTURE OBJECTIVES • Disinfectants n • Knowledge and controversies Detergents n • Knowledge and controversies Microfiber n Knowledge and controversies

CLEANING AND DISINFECTING ENVIRONMENTAL SURFACES Cleaning (removes soil) and disinfecting is one-step with disinfectant-detergent. No pre-cleaning necessary unless spill or gross contamination.

LOW-LEVEL DISINFECTION FOR NONCRITICAL EQUIPMENT AND SURFACES Germicide Exposure time > 1 min Use Concentration Ethyl or isopropyl alcohol 70 -90% Chlorine 100 ppm (1: 500 dilution) Phenolic UD Iodophor UD Quaternary ammonium UD Improved hydrogen peroxide 0. 5%, 1. 4% ________________________ UD=Manufacturer’s recommended use dilution

DISINFECTION OF NONCRITICAL PATIENT-CARE DEVICES Rutala, 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 offlabel use and is potentially subject to enforcement action under FIFRA. (II, IC)

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

CONTACT TIMES FOR SURFACE DISINFECTION • • Follow the EPA-registered contact times, ideally n Some products have achievable contact times for bacteria/viruses (30 seconds-2 minutes) n Other products have non-achievable contact times If use a product with non-achievable contact time n Use >1 minute based on CDC guideline and scientific literature n Prepare a risk assessment http: //www. unc. edu/depts/spice/dis/Surf. Dis. Risk. Asse ss 2011. pdf

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)

Surface Disinfection: Should We Do It? The use of disinfectants for non-critical items in health care is controversial (especially in some parts of the world)

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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 persistent antimicrobial activity

ENVIRONMENTAL CONTAMINATION LEADS TO HAIs • Microbial persistence in the environment n n • Frequent environmental contamination n • MRSA, VRE, Ab, Cd HCW hand contamination n • In vitro studies and environmental samples MRSA, VRE, Ab, Cd Relationship between level of environmental contamination and hand contamination n Cd

ENVIRONMENTAL CONTAMINATION LEADS TO HAIS • Person-to-person transmission n n • Housing in a room previously occupied by a patient with the pathogen of interest is a risk factor for disease n • Molecular link MRSA, VRE, Ab, Cd MRSA, VRE, Cd, Ab Improved surface cleaning/disinfection reduces disease incidence n MRSA, VRE, Cd

RELATIVE RISK OF PATHOGEN ACQUISITION IF PRIOR ROOM OCCUPANT INFECTED * Prior room occupant infected; ^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 l l 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% n Admission to room not previously occupied by CDI = 4. 6% (p=0. 002) Shaughnessy MK, et al. ICHE 2011; 32: 201 -206 n

KEY PATHOGENS WHERE ENVIRONMENTIAL SURFACES PLAY A ROLE IN TRANSMISSION • • MRSA VRE Acinetobacter spp. Clostridium difficile Norovirus Rotavirus SARS

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

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 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 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: 185 -187

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), 3 rd ed, 2010.

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

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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

Disinfectant Product Subsitutions 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. May 2013 “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”

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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

Surface Disinfection Effectiveness of Different Methods Rutala, Gergen, Weber. 2013, Unpublished Resutls Technique (with cotton) MRSA Log 10 Reduction (QUAT) Saturated cloth 4. 41 Spray (10 s) and wipe 4. 41 Spray, wipe, spray (1 m), wipe 4. 41 Spray, wipe, spray (until dry) 4. 41 Disposable wipe with QUAT 4. 55 Control: detergent 2. 88

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. 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

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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

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

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

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

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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

QUATS AS SURFACE DISINFECTANTS WITH PERSISTENT ACTIVITY l l l Study of computer keyboards: Challenge with VRE or P. aeruginosa Keys wiped with alcohol or quats (Cavi. Wipes, 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.

Justification for Using a Disinfectant for Non-Critical Surfaces • • • 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

LECTURE OBJECTIVES • Disinfectants n • Knowledge and controversies Detergents n • Knowledge and controversies Microfiber n Knowledge and controversies

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs Occupational health exposure issues Use of antiseptics and disinfectants may select for antibiotic resistant bacteria Less environmental impact

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants n • • Contaminated surfaces provide an important potential source for transmission of HA pathogens. Greater than 20 studies have demonstrated that environmental disinfection interventions can end outbreaks or decrease incidence of HAIs Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs, occupational health exposure issues, less environmental impact

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) n • Given the high prevalence of epidemiologically-important pathogens in most countries in the world and that routine screening is rarely conducted, we should employ disinfectants for all hospitalized patients as unsuspected colonization is a routine occurrence Costs, occupational health exposure issues, less

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs-approx same QUAT-$0. 16 -0. 20/use gal ($20/1: 128 dil) vs detergent-$0. 23/use gal ($15/1: 64 dil) Occupational health exposure issues Use of antiseptics and disinfectants may select for antibiotic resistant bacteria

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs Occupational health exposure issues Use of antiseptics and disinfectants may select for antibiotic resistant bacteria Less environmental impact

Occupational Exposures to Disinfectants at UNC Health Care • • In regard to skin or respiratory irritation and allergies in HCP, most studies refer to glutaraldehyde or formaldehyde, these products are not recommended for use on noncritical surfaces Surface disinfection in US generally accomplished by QUAT, phenolic, improved HP and chlorine We are evaluating all chemical exposures for ten years (20032012, 9500 employees) and have rarely seen an employee in OHS with chronic respiratory complaint related to a low-level disinfectant (~30 M persons days of exposure [Weber, Rutala, Consoli. 2013. Unpublished data]) Need well-designed immunologic evaluations of randomly selected HCP and controls, not case series without controls

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs Occupational health exposure issues Use of antiseptics and disinfectants may select for antibiotic resistant bacteria Less environmental impact

Is There A Relationship Between Germicide Use and Antibiotic Resistance Weber DJ, Rutala WA. ICHE 2006; 27: 1107 -1119 • • • Possible to develop mutants in the laboratory with reduced susceptibility to disinfectants and antiseptics ( 1 ppm to 4 ppm, triclosan) that demonstrate decreased susceptibility or resistance to antibiotics. Concentration of triclosan used in practice greatly exceed the MICs observed (4 vs 2000 -20, 000 ppm), the clinical relevance is questionable To date no evidence that using antiseptics or disinfectants selects for antibiotic-resistant organisms or that mutants survive in nature Antibiotic-resistant bacteria are as susceptible to germicides as antibiotic-susceptible strains Germicides should be used where there are scientific studies

Justifications Used by Some for Using a Detergent for Non-Critical Surfaces • • Environmental surfaces and noncritical patient care items contribute minimally to healthcare-associated infections No difference in HAI rates when surfaces are cleaned with detergents versus disinfectants Use disinfectants for epidemiologically-important pathogens (MRSA, VRE) Costs Occupational health exposure issues Use of antiseptics and disinfectants may select for antibiotic resistant bacteria Less environmental impact

Environmental Impact • Bleach Reacts with soils, bacteria and stains; 95 -98% rapidly breaks down to salt and water; remaining 25% treated by sewer and septic systems n Does not contaminate ground water because it does not survive sewage treatment n • QUATs n Almost completely degraded in sewage sludge

How About “Green” Products? • • Today, the definition of green is unregulated It can mean: n n n • n 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

LECTURE OBJECTIVES • Disinfectants n • Knowledge and controversies Detergents n • Knowledge and controversies Microfiber n Knowledge and controversies

Wipes Cotton, Disposable, Microfiber, Cellulose-Based, Nonwoven Spunlace

Wipes Cotton, Disposable, Microfiber, Cellulose-Based, Nonwoven Spunlace Wipe should have sufficient wetness to achieve the disinfectant contact time. Discontinue use of a disposable wipe if it no longer leaves the surface visibly wet for > 1 m

Microfiber Cloth/Wipe/Pads

Microfiber Cleaning • • • Pad contains fibers (polyester and polyamide) that provide a cleaning surface 40 times greater than conventional string mops Proposed advantages: reduce chemical use and disposal (disinfectant solution not changed after every third room, clean microfiber per room [washing lifetime 500 -1000 x]); light (~5 lb less than string mop) and ergonomic; reduce cleaning times. Does the microfiber provide the same or better removal of microorganisms on surfaces?

Efficacy of Different Microfiber Cloths at Removing Surface Microorganisms Smith et al. J Hosp Infect 2011; 78: 182 -186 • Mean log 10 reduction ~2. Overall mean differences in the performance of individual, reusable cloths showed a log 10 reduction of <1.

Mean Number of C. difficile Removed from Laminate on Repeat Washings of Cloths Smith et al. J Hosp Infect 2011; 78: 182 -186 • Mean log 10 reduction was >2. The performance of the reusable cloths improved initially, but then slightly declined after 150 washes

Effectiveness of Microfiber Mop (Rutala, Gergen and Weber, Am J Infect Control, 2007; 35: 569) Disinfectant-regular mop 95% Disinfectant-microfiber system 95% Disinfectant-microfiber mop and regular mop bucket Detergent-regular mop 88% Detergent-microfiber system 95% Detergent-microfiber mop and regular mop bucket 78% 68%

Microfiber Efficacy and Use • • • > 2 log 10 reduction for microbial removal. Smith et al. JHI. 2011; 78: 182 Currently, we use the microfiber mops for the floors with a disinfectant. We use several cotton, wiping cloths per room for elevated surfaces but are transitioning to microfiber cloths We use a disinfectant because cleaning cloths such as microfiber or cotton can disperse microorganisms when a disinfectant is not incorporated or is depleted The ability of cotton/microfiber to retain QUATs ensures that microbes in contact with cloth/pad are also in contact with QUAT and will not redeposit on surface Instructions on preparation, use, and washing should be followed to maximize cloth performance

Microbial Contamination of Reusable Cleaning Cloths Sifuentes et al. AJIC. Epub. 2013 Microfiber towels harbor greater numbers of bacteria compared with the cotton towels

Microbial Contamination of Reusable Cleaning Cloth Rutala, Gergen, Weber. AJIC 2007; 35: 569 • • • Hospital laundering practices should be assessed to ensure they are sufficient to remove all viable microorganisms from microfiber Microfiber may have special laundering processes (may exclude bleach, fabric softeners, wash temperatures <200 o. C and drying less <140 o. C) Our assessment of our routine laundering cycle

Wipes Cotton, Disposable, Microfiber, Cellulose-Based, Nonwoven Spunlace

Optimizing Disinfectant Application in Healthcare Facilities KD Mac. Dougall, C Morris. Infection Control Today. June 2006 Significant decline in the concentration of QUAT when cotton rags or cellulose-based wipers were compared to nonwoven spunlace wipers

Optimizing Disinfectant Application in Healthcare Facilities KD Mac. Dougall, C Morris. Infection Control Today. June 2006 • Do different wipes provide a higher active QUAT concentration: yes n n • Virgin cotton rags and cellulose-based wipers: 30 -70% drop in QUAT concentration in first 3 hours Nonwoven spunlace wipers with a fiber content intended to yield QUAT compatibility: ~10 -15% drop Summary-Nonwoven spunlace wipers maintain the QUAT concentration released to surface at near target concentration levels. A sharp reduction in QUAT with cotton, microfiber and cellulose-based wipers (electrostatic attraction between two oppositely charged ions [quats +, bacteria/cotton/microfiber -]). The QUAT retained in cotton/microfiber ensures that microbes in contact with cloth/pad are also in contact with QUAT and

Effectiveness of Different Wipes and Solutions in Removing MRSA from Surface Rutala, Gergen, Weber. Unpublished results. 2013 Even though cotton and microfiber retain QUAT, they provide equivalent removal/inactivation of MRSA from surface (log 10 reduction) as nonwoven spunlace wiper Solution Cotton KC 06411 Microfiber Cellulose Sterile Water 3. 07 3. 22 3. 88 2. 39 Detergent 2. 88 3. 08 3. 47 3. 13 QUAT 1 4. 41 4. 60 4. 51 4. 40 QUAT 2 3. 76 3. 74 3. 87 2. 75

Objective Describe emerging knowledge and controversies related to disinfectants, detergents and microfiber cleaning products

Disinfectants, Detergents and Microfiber Summary • • Contaminated surface environment in hospital rooms is important in transmission of HA pathogens Appropriate use of disinfectants prevent transmission of pathogens and reduce HAIs Detergents alone do not kill pathogens and can crosscontaminate the environment Microfiber cloths are effective in removing microorganisms from surfaces. To prevent dispersion of microbes we use a disinfectant.

THANK YOU!

www. disinfectionandsterilizatio n. org