“No Touch” Methods for Room Disinfection

Dr. Bill Rutala

There is excellent evidence in the scientific literature that environmental contamination plays an important role in the transmission of several key healthcare-associated pathogens including methicillin-resistant Staphylococcus aureus [MRSA] , vancomycin-resistant Enterococcus [VRE], Acinetobacter, norovirus, and Clostridium difficile.^1-4  All these pathogens have been demonstrated to persist in the environment for hours to days (in some cases months)⁵, to frequently contaminate the environmental surfaces in rooms of colonized or infected patients, to transiently colonize the hands of healthcare personnel, to be transmitted by healthcare personnel, and to cause outbreaks in which environmental transmission was deemed to play a role.  Further, admission to a room in which the previous patient had been colonized or infected with MRSA, VRE, Acinetobacter or C. difficile, has been shown to be a risk factor for the newly admitted patient to develop colonization or infection.^6-8

It has long been recommended in the United States that environmental surfaces in patient rooms be cleaned/disinfected on a regular basis (e.g., daily, 3 times per week), when surfaces are visibly soiled, and following patient discharge (terminal cleaning).⁹   Studies have demonstrated that adequate environment cleaning is frequently lacking.  For example, Carling and co-workers assessed the thoroughness of terminal cleaning in the patient’s immediate environment in 23 acute care hospitals (1,119 patient rooms) by using a transparent, easily cleaned, stable solution that fluoresces when exposed to hand-held ultraviolet (UV) light.¹⁰   The overall thoroughness of cleaning, expressed as a percent of surfaces evaluated, was 49% (range for all hospitals, 35%-81%).  Further, while interventions aimed at improving cleaning thoroughness have demonstrated effectiveness, many surfaces remain inadequately cleaned and therefore potentially contaminated.  For this reason, several manufacturers have developed room disinfection units that can decontaminate environmental surfaces and objects.  These systems use one of two methods; either ultraviolent light or hydrogen peroxide.^{11, 12}  These technologies supplement, but do not replace, standard cleaning and disinfection because surfaces must be physically cleaned of dirt and debris.  Additionally, these methods can only be used for terminal or discharge room decontamination (i.e., cannot be used for daily room decontamination) because the room must be emptied of people.   This article summarizes a recent publications of this topic. ¹³

Ultraviolet Light for Room Decontamination

                UV irradiation has been used for the control of pathogenic microorganisms in a variety of applications, such as control of legionellosis, as well as disinfection of air, surfaces, and instruments.^{14, 15} At certain wavelengths, UV light will break the molecular bonds in DNA, thereby destroying the organism.  UV-C has a characteristic wavelength of 200-270 nm (e.g., 254 nm), which lies in the germicidal active portion of the electromagnetic spectrum of 200-320 nm.  The efficacy of UV irradiation is a function of many different parameters such as intensity, exposure time, lamp placement, and air movement patterns.

                An automated mobile UV-C unit (Tru-D, Lumalier Corporation) has been shown to eliminate >3-log₁₀ vegetative bacteria (MRSA, VRE, Acinetobacter baumannii) and >2.4-log₁₀ C. difficile seeded onto formica surfaces in patients’ rooms experimentally contaminated.⁴   There are three studies that have demonstrated that this UV-C system is capable of reducing vegetative bacteria inoculated on a carrier by >3-4-log₁₀ in 15-20 minutes and C. difficile by >1.7-4-log₁₀ in 35-100 minutes.^{4, 16, 17}  The studies  demonstrate reduced effectiveness when surfaces were not in direct line-of-sight.  Investigators have also demonstrated the effectives of an automated ultraviolet-C emitter against VRE, MRSA, Acinetobacter spp and C. difficile in patient rooms^{4, 18} and used a nanostructured UV-reflective wall coating that significantly reduced the time (from 25 minutes to 5 minutes for MRSA and from 44 minutes to 9 minutes for C. difficile spores) necessary to decontaminate a room using a UV-C-emitting device.¹⁹

Hydrogen Peroxide (HP) Systems for Room Decontamination

                Several systems which produce hydrogen peroxide (e.g., HP vapor, aerosolized dry mist HP, vaporized HP) have been studied for their ability to decontaminate environmental surfaces and objects in hospital rooms.  A system using hydrogen peroxide vapor has been demonstrated to completely inactivate >10⁶ Bacillus stearothermophilus spores contained in biologic indicators hung in patient rooms and almost eliminate all MRSA surface contamination.²⁰  Other studies have also demonstrated the ability of HP systems to almost eliminate MRSA, VRE, M. tuberculosis, spores, viruses and multidrug-resistant Gram-negative bacilli.^21-23  Using a before-after design, Boyce and coworkers have previously shown that use of the HP systems was associated with a significant reduction in the incidence of C. difficile infection on 5 high-incidence wards.²⁴  A recent paper by Passaretti and colleagues demonstrated that environmental decontamination with HPV reduced the risk of a patient admitted to a room previously occupied by a colonized or infected patient with a MDRO from acquiring an MDRO by 64% compared to using standard disinfection methods.²⁵   However, HP system decontamination was shown to require more than 4-times longer to complete than conventional cleaning thus resulting in prolonged bed turn-over time.²⁶ 

Comparison of UV Irradiation Versus Hydrogen Peroxide for Room Decontamination

                The UV-C system and the systems which use hydrogen peroxide have their own advantages and disadvantages (Table).  The main advantage of both units is their ability to achieve substantial reductions in vegetative bacteria.  As noted above, manual cleaning has been demonstrated to be suboptimal as many environmental surfaces are not cleaned.  Another advantage is their ability to substantially reduce C. difficile spores as low-level disinfectants (such as quaternary ammonium compounds) have only limited or no measurable activity against spore-forming bacteria.   Both systems are residual free and they decontaminate all exposed surfaces and equipment in the room.

                The major disadvantages of both decontamination systems are the substantial capital equipment costs, the need to remove personnel and patients from the room thus limiting their use to terminal room disinfection (must prevent/minimize exposure to UV and HP), the staff time needed to transport the system to rooms to be decontaminated and monitor its use, and the need to physically clean the room of dust and debris.  There are several important differences between the two systems.  The UV-C system offers faster decontamination which reduces the “down” time of the room before another patient can be admitted.  The HP systems have been demonstrated to be more effective in eliminating spore-forming organisms.  Whether this improved sporicidal activity is clinically important is unclear as studies have demonstrated that although environmental contamination is common in the rooms of patients with C. difficile infection, the level of contamination is relatively low (also true for MRSA, VRE).  Finally, the HP system was demonstrated to reduce C. difficile incidence in a clinical study while similar studies with the UV-C system have not been published. 

Conclusion

There is now ample evidence that “no touch” systems such as UV-C or hydrogen peroxide can reduce environmental contamination with healthcare-associated pathogens.  However, each specific system should be studied and their efficacy demonstrated  before introduction into healthcare facilities.  Additional studies assessing the effectiveness of “no touch” room decontamination systems are needed to further assess the benefits of these technologies.  In addition, cost-effectiveness studies would be useful in aiding selection among the different room decontamination technologies and specific systems.  Lastly, if additional studies continue to demonstrate benefit, widespread adoption of these technologies (e.g., a supplemental intervention during outbreaks, after discharge of patients on Contact Precautions, on a regular basis in special rooms [e.g., operating rooms]) should be considered for terminal room disinfection in healthcare facilities. 

Table.  Advantages and Disadvantages of Room Decontamination by Ultraviolet (UV) Irradiation and Hydrogen Peroxide (HP)^12,13

Ultraviolet Irradiation

         Advantages

• Reliable biocidal activity against a wide range of healthcare-associated pathogen
• Room surfaces and equipment decontaminated
• Room decontamination is rapid (~15-25 minutes) for vegetative bacteria
• Effective against Clostridium difficile, although requires longer exposure (~50 minutes)
• HVAC (heating, ventilation and air conditioning) system does not need to be disabled and the room does not need to be sealed
• UV is residual free and does not give rise to health or safety concerns
• No consumable products so costs include only capital equipment and staff time
• Good distribution in the room of UV energy via an automated monitoring system

         Disadvantages

• All patients and staff must be removed from the room prior to decontamination
• Decontamination can only be accomplished at terminal disinfection (i.e., cannot be used for daily disinfection) as room must be emptied of people
• Capital equipment costs are substantial
• Does not remove dust and stains which are important to patients and visitors, and hence cleaning must precede UV decontamination
• Sensitive to use parameters (e.g., wavelength, UV dose delivered)
• Requires that equipment and furniture be moved away from the walls
• Studies have not been conducted to demonstrate whether use of UV room decontamination decreases the incidence of healthcare-associated infections

Decontamination by Hydrogen Peroxide Systems

         Advantages

• Reliable biocidal activity against a wide range of healthcare-associated pathogens
• Room surfaces and equipment decontaminated
• Effective against Clostridium difficile
• Useful for disinfecting complex equipment and furniture
• Does not require that furniture and equipment be moved away from the walls
• HP is residual free and does not give rise to health or safety concerns (aeration unit converts HP into oxygen and water)
• Uniform distribution in the room via an automated dispersal system
• Demonstrated to reduce healthcare-associated infections (i.e., Clostridium difficile)

         Disadvantages

• All patients and staff must be removed from the room prior to decontamination
• HVAC system must be disabled to prevent unwanted dilution of HP during use and the doors must be closed with gaps sealed by tape
• Decontamination can only be accomplished as terminal disinfection (i.e., cannot be used for daily disinfection) as room must be emptied of people
• Capital equipment costs are substantial
• Decontamination requires ~2.5 to 5 hours
• Does not remove dust and stains which are important to patients and visitors, and hence cleaning must precede UV decontamination
• Sensitive to use parameters (e.g., HP concentration)

References

1.            Dancer SJ. The role of environmental cleaning in the control of hospital-acquired infection. J Hosp Infect 2009;73:378-85.

2.            Boyce JM. Environmental contamination makes an important contribution to hospital infection J Hosp Infect 2007;65:50-4.

3.            Weber DJ, Rutala WA, Miller MB, Huslage K, Sickbert-Bennett E. Role of hospital surfaces in the transmission of emerging health care-associated pathogens: Norovirus, Clostridium difficile, and Acinetobacter species. Am J Infect Control 2010;38:S25-33.

4.            Rutala WA, Gergen MF, Weber DJ. Room decontamination by ultraviolet radiation. Infect  Control Hosp Epidemiol 2010;31:1025-9.

5.            Kramer A, Schwebke I, Kampf G. How long do nosocomial pathogens persist on inanimate surfaces? A systematic review. BMC Infect Dis 2006;6:130.

6.            Huang SS, Datta R, Platt R. Risk of acquiring antibiotic-resistant bacteria from prior room occupants. Arch Int Med 2006;166:1945-51.

7.            Shaughnessy MK, Micielli RL, DePestal DD, et al. Evaluation of hospital room assignment and acquisition of Clostridium difficile infection. Infect Control Hosp Epidemiol 2011;32:201-6.

8.            Otter JA. The role played by contaminated surfaces in the transmission of nosocomial pathogens. Infect Control Hosp Epidemiol 2011;32:687-99.

9.            Rutala WA, Weber DJ, Healthcare Infection Control Practices Advisory Committee. Guideline for disinfection and sterilization in healthcare facilities, 2008. In: cdcgov/ncidod/dhqp/pdf/guidelines/Disinfection_Nov_2008pdf

10.          Carling PC, Parry MF, Von Beheren SM, Healthcare Environmental Hygiene Study Group. Identifying opportunities to enhance environmental cleaning in 23 acute care hospitals. Infect  Control Hosp Epidemiol 2008;29:1-7.

11.          Davies A, Pottage T, Bennett A, Walker J. Gaseous and air decontamination technologies for Clostridium difficile in the healthcare environment. J Hosp Infect 2011;77:199-203.

12.          Rutala WA, Weber DJ. Are room decontamination units needed to prevent transmission of environmental pathogens? Infect Control Hosp Epidemiol 2011;32:743-7.

13.          Rutala WA, Weber DJ. Disinfectants used for environmental disinfection and new room decontamination technology

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

14.          Rutala WA, Weber DJ. Sterilization, high-level disinfection, and environmental cleaning. Infect Dis Clin N Am 2011;25:45-76.

15.          Memarzadeh F, Olmsted RN, Bartley JM. Applications of ultraviolet germicidal irradiation disinfection in health care facilities: Effective adjunct, but not stand-alone technology. Am J Infect Control 2010;38:S13-S24.

16.          Boyce JM, Havill NL, Moore BA. Terminal decontamination of patient rooms using an automated mobile UV light unit

Infect Control Hosp Epidemiol 2011;32:743-7.

17.          Nerandzic MM, Cadnum JL, Pultz MJ, Donskey CJ. Evaluation of an automated ultraviolet radiation device for decontamination of Clostridium difficile and other healthcare-associated pathogens in hospital rooms. BMC Infect Dis 2010;10:197.

18.          Anderson DJ, Gergen MF, Smathers E, et al. Decontamination of targeted pathogens from patient rooms using an automated ultraviolet-C-emitting device. Infect Control Hosp Epidemiol 2013;34:465-71.

19.          Rutala WA, Gergen MF, Tande BM, Weber DJ. Rapid hospital room decontamination using ultraviolet (UV) light with a nanostructured UV-reflective wall coating. Infect Control Hosp Epidemiol 2013;34:527-9.

20.          French GL, Otter JA, Shannon KP, Adams NMT, Watling D, Parks MJ. Tackling contamination of the hospital environment by methicillin-resistant Staphylococcus aureus (MRSA): A comparison between conventional terminal cleaning and hydrogen peroxide vapour decontamination. J Hosp Infection 2004;57:31-7.

21.          Falagas ME, Thomaidis PC, Kotsantis IK, Sgouros K, Samonis G, Karageorgopoulos DE. Airborne hydrogen peroxide for disinfection of the hospital environment and infection control: a systematic review. J Hosp Infect 2011;78:171-7.

22.          Hall L, Otter JA, Chewins J, Wengenack NL. Use of hydrogen peroxide vapor for deactivation of Mycobacterium tuberculosis in a biological safety cabinet and a room. J Clin Microbiol 2007;45:810-5.

23.          Bentley K, Dove BK, Parks SR, Walker JT, Bennett AM. Hydrogen peroxide vapour decontamination of surfaces artifically contaminated with norovirus surrogate feline calicivirus. J Hosp Infect 2012;80:116-21.

24.          Boyce JM, Havill NL, Otter JA, et al. Impact of hydrogen peroxide vapor room decontamination on Clostridium difficile environmental contamination and transmission in a healthcare setting. Infect  Control Hosp Epidemiol 2008;29:723-9.

25.          Passaretti CL, Otter JA, Reich NG, et al. An evaluation of environmental decontamination with hydrogen peroxide vapor for reducing the risk of patient acquisition of multidrug-resistant organisms. Clin Infect Dis 2013;56:27-35.

26.          Otter JA, Puchowicz M, Ryan D, et al. Feasibility of routinely using hydrogen peroxide vapor to decontaminate rooms in a busy United States hospital. Infect  Control Hosp Epidemiol 2009;30:574-7.