Healthcare-Associated Infections and Environmental Disinfection in Nursing Homes

Healthcare-associated infections (HAIs), defined by the Centers for Disease Control and Prevention (CDC) as “infections caused by a wide variety of common and unusual bacteria, fungi, and viruses during the course of receiving medical care,”¹ were first observed in the acute hospital setting.² As a result, these infections are commonly referred to as nosocomial infections, hospital-acquired infections, and hospital-onset infections throughout the medical literature; however, healthcare-associated infections is now the preferred term because these infections can occur in any healthcare setting. In the United States, there are approximately 1.7 million HAIs annually, resulting in >100,000 deaths.³ These grim statistics highlight the seriousness of this issue.

Requirements for infection transmission include the presence of an infectious agent, a susceptible host, and a means of transmission.⁴ All of these requirements are met in nursing homes (NHs), and because the NH population is largely made up of elders, this population is at especially high risk of contracting HAIs and experiencing considerable morbidity and mortality following an infection. The CDC and the Healthcare Infection Control Practices Advisory Committee (HICPAC) acknowledge that exposure to environmental opportunistic pathogens or airborne pathogens in these settings can have serious consequences for healthcare workers and residents, especially those with compromised immune systems, such as frail elders.³ With an increasing number of individuals—many of whom have preexisting comorbidities that make them susceptible to infections—entering US long-term care (LTC) facilities each year,⁵ reducing this population’s exposure to environmental pathogens is imperative, especially because many pathogens are becoming increasingly resistant to available treatments. In the NH setting, environmental disinfection is a key component of the infection prevention and control process. This article discusses important considerations of environmental disinfection in the NH setting.

Breaking the Chain of Transmission

The physical number of microorganisms present on any given surface is influenced by a number of factors, including the amount of moisture on the surface, the amount of activity taking place in the immediate environment, the number of people having contact with the environment, and the type of environmental surfaces present and their ability to support microbial growth. In the NH setting, methicillin-resistant Staphylococcus aureus, Escherichia coli, and Clostridium difficile are common pathogens, and they can survive on surfaces for days to months. With such longevity, transmission of these and other harmful environmental pathogens can easily occur. Because residents have communal living spaces and are often ambulatory, they can unwittingly spread pathogens throughout the facility, increasing the risk of cross-transmission.⁶ Once a surface becomes contaminated, it can serve as a reservoir for microbial growth. If a resident or a facility staff member touches this surface and then makes contact with another device or surface, a chain of HAI transmission may begin.

Because microorganisms are becoming progressively more adept at surviving and reproducing on environmental surfaces, while also developing increased resistance to available treatments, breaking the chain of transmission is imperative. Routine environmental disinfection can play an integral role in breaking this chain and reducing the risk of transmission.

Environmental Disinfection

Before effective disinfection can be undertaken, all visibly soiled environmental surfaces must be cleaned. In 2008, the CDC issued a guideline for disinfection and sterilization in healthcare facilities, which defined cleaning as “the removal of foreign material (eg, soil, organic matter) from objects, [which] is normally accomplished using water with detergents or enzymatic products.”⁷ The guidelines note that cleaning removes bioburden from the affected surface by reducing the number of microorganisms that must be inactivated.⁷ Removing bioburden before applying the disinfectant solution ensures maximum efficacy of the disinfectant.

While cleaning a surface, it is also important to apply friction. Friction helps remove more resistant forms of microorganisms (eg, spores), which may not be readily inactivated by the disinfectant. For example, when conditions in a host or the environment become unfavorable for C. difficile to survive in its vegetative state (the state in which it is actively growing), it forms an endospore and becomes dormant. In the endospore stage, C. difficile is extremely hardy and is not easily destroyed by disinfectants. Proper cleaning in combination with effective disinfection can decrease the number of pathogens, including endospores, on environmental surfaces, reducing the risk for the development of multidrug-resistant organisms, which have a well-documented history of transmission.

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What to Disinfect

To decrease the risk of cross-transmission and development of HAIs in LTC facilities, cleaning and disinfection of all medical equipment and environmental surfaces must be routinely undertaken.⁵ The disinfection protocol for each item and surface will vary, depending on how likely it is to transmit pathogens to residents and staff. The CDC advocates categorizing items and surfaces as noncritical, semicritical, and critical, according to the classification scheme developed by Earle H. Spaulding, PhD, a microbiologist and immunologist, approximately 30 years ago.⁷ This scheme, often referred to as the Spaulding scheme, is also used by the US Food and Drug Administration, epidemiologists, microbiologists, and professional medical organizations around the world to aid in determining the degree of disinfection or sterilization required for various environmental surfaces and medical equipment.

Noncritical Items
In the LTC setting, many items are considered noncritical. The CDC defines noncritical items as “those that come in contact with intact skin but not mucous membranes.”⁷ These include certain patient care items, such as wheelchairs and bedpans, as well as general surfaces, such as floors and furniture. Because noncritical items are unlikely to transmit infections, the use of a low-level disinfectant is adequate and appropriate for these items; some low-level disinfectants are outlined in the Table. Healthcare providers should keep in mind that noncritical items used on multiple residents require more frequent disinfection with low-level disinfectants to prevent pathogens from being transmitted between residents. Such items include medical equipment with high-touch surfaces, such as blood pressure cuffs, stethoscopes, and glucometers.

Because there are so many noncritical surfaces and items in NHs, it is easy to overlook some of them, especially if it is an item residents do not have contact with. Examples include office equipment such as computer keyboards, mice, and phone receivers. While most people do not think of such equipment as harboring dangerous microorganisms, a report by a British consumer group in 2008 provided some startling findings,namely, swabs taken from 33 keyboards at the group’s London office revealed that many of the keyboards were dirtier than a typical toilet seat, with one keyboard having 150 times the recommended limit of bacteria.⁸ With health institutions increasingly migrating to electronic medical records, more staff may be accessing computer stations, increasing the risk of pathogens being transmitted throughout these facilities. While hand hygiene is still the most useful intervention to break the chain of infection in such cases, routine disinfection of any potential reservoirs for microbial growth is also important.

Semicritical Items
The CDC defines semicritical items as those that “come in contact with mucous membranes or intact skin.”⁷ Examples of such items that may be used in LTC settings include respiratory equipment, diaphragm fitting rings, and intubation equipment. When disinfecting these items, the objective is to eliminate all vegetative microorganisms, including viruses, bacteria, fungi, and mycobacteria; a small number of spores are permissible.⁷ These items require high-level disinfection, which can be accomplished with chemical disinfectants, such as those outlined in the Table.

Critical Items
Critical items are those that “confer a high risk for infection if they are contaminated with any microorganism.”⁷ They include medical equipment that comes into contact with sterile tissue or enters the vascular system. While critical items are more common in the acute care setting, urinary catheters are an example of a critical item commonly used in NHs. Because any microbial contamination of critical items can be devastating to residents, critical items are packaged as sterile or are reprocessed and then sterilized. If the item is reusable, the CDC recommends sterilization with steam whenever possible. Heat-sensitive items can instead be sterilized with ethylene oxide, a low-temperature sterilant that has been widely used since the 1950s; hydrogen peroxide gas plasma, which has been marketed in the United States since the early 1990s; or with a high-level liquid chemical sterilant if no other options are suitable or available.⁷

Disinfectant Selection

There are many disinfectants on the market, which may make the selection process somewhat overwhelming. When shopping for a disinfectant, it is crucial to look for one that is registered with the US Environmental Protection Agency, as these products can be used with minimal risk if the label directions are followed properly. It is also important to refer to the facility’s risk assessment, so that a disinfectant with efficacy claims against microorganisms routinely found within that facility can be located. Efficacy claims are readily available from product manufacturers, often on their Websites, and should be carefully reviewed before using the product in the facility to ensure it is used appropriately.⁹

Collaboration and Education
Because each department and staff member has a responsibility in the cleaning and disinfection process, it is crucial to have a complete set of policies and procedures in place outlining these responsibilities for noncritical, semicritical, and critical items. Careful collaboration with the environmental services team is necessary to make sure all surfaces and items are accounted for in the cleaning plan and that these surfaces and items are routinely disinfected by the appropriate personnel. The environmental services
team also plays an instrumental role in educating the healthcare and housekeeping staff on how to properly use disinfectant products, thereby minimizing risks associated with the use of such products and ensuring effective disinfection. Education should outline the appropriate indications for using the chosen product(s), as some disinfectants may be inappropriate on certain surfaces (eg, hydrogen peroxide solutions can corrode certain metals); provide instructions for use, including the total overall contact time required to effectively inactivate microorganisms (this information is outlined on the product’s label); review the material safety data sheet; and discuss appropriate use of personal protective equipment, which is required by the Occupational Safety and Health Administration’s bloodborne pathogens standard. Educational programs are available through organizations such as the Association for Professionals in Infection Control and Epidemiology (www.apic.org) and the Association for the Healthcare Environment (www.ahe.org).

Take-Home Message

A thorough cleaning and disinfection program combined with hand hygiene and careful selection of the most appropriate hospital-grade disinfectant will dramatically improve the healthcare professional’s ability to combat HAIs in the NH setting. Educating staff on the proper use of the chosen disinfectant will ensure their and residents’ safety and maximize the efficacy of the disinfectant. With the development of new surface disinfection technologies each year, it is crucial for healthcare providers to keep abreast of their options; however, before adopting any new product, a thorough review of the supporting efficacy data is always warranted.

Dr. Garrett is employed by Professional Disposables International (PDI), Inc, a company that specializes in developing, testing, and manufacturing disinfecting products.

Dr. Garrett is director, Clinical Affairs and Corporate Training, Professional Disposables International (PDI), Inc, and is based in Atlanta, GA. He currently serves as vice president, the Vascular Access Certification Corporation (VACC); president-elect, Southeast Chapter, Infusion Nurses Society (INS); member, Association of periOperative Registered Nurses (AORN) Recommended Practices Advisory Board; and education chair, Greater Atlanta Chapter, Association for Professionals in Infection Control and Epidemiology (APIC). He is also an active member of the Society for Healthcare Epidemiology of America (SHEA), the Infectious Diseases Society of America (IDSA), and the American Association for Long Term Care Nursing (AALTCN).

 References

1. US Centers for Disease Control and Prevention. Healthcare-associated infections (HAIs). www.cdc.gov/hai/index.html. Updated September 1, 2011. Accessed September 20, 2011.

2. Coffin SE, Zaoutis TE. Healthcare-Associated Infections. In: Long SS, Pickering LK, Prober CG, eds. Principles and Practice of Pediatric Infectious Diseases. 3rd ed. Philadelphia, PA: Churchill Livingstone; 2008.

3. Sehulster L, Chinn RYW. Guidelines for environmental infection control in health-care facilities: recommendations of CDC and the Healthcare Infection Control Practices Advisory Committee (HICPAC) [published correction appears in MMWR Morb Mortal Wkly Rep. 2003;52(42):1025-1026]. MMWR Morb Mortal Wkly Rep. 2003;52(RR-10):1-42. www.cdc.gov/mmwr/preview/mmwrhtml/rr5210a1.htm. Accessed September 20, 2011.

4. Smith PW, Rusnak PG. SHEA/APIC position paper: infection prevention and control in the long-term care facility. Infect Control Hosp Epidemiol. 1997;18(12):831-849.

5. Smith PW, Bennett G, Bradley S, et al. SHEA/APIC guideline: infection prevention and control in the long-term care facility. Infect Control Hosp Epidemiol. 2008;29(9):785-814.

6. Association for Professionals in Infection Control and Epidemiology. Guide to the elimination of methicillin-resistant Staphylococcus aureus (MRSA) in the long-term care facility. https://www.apic.org/Content/NavigationMenu/PracticeGuidance/APIC
EliminationGuides/MRSA_in_LTC_09.pdf. Published 2009. Accessed September 19, 2011.

7. Rutala WA, Weber DJ; Healthcare Infection Control Practices Advisory Committee. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008. www.cdc.gov/hicpac/pdf/guidelines/Disinfection_Nov_2008.pdf. Published 2008. Accessed September 19, 2011.

8. Keyboards ‘dirtier than a toilet.’ BBC News. Published May 1, 2008. https://news.bbc.co.uk/2/hi/7377002.stm. Accessed September 22, 2011.

9. US Environmental Protection Agency. www.epa.gov. Updated 2011. Accessed September 19, 2011.