How ‘Clean’ Is the Hospital Environment?
A recent multistate survey of 183 acute care hospitals in the United States revealed that approximately 1 of every 25 inpatients developed at least one healthcare–associated infection per day.[1] Clostridioides difficile was reported as the most common healthcare–associated pathogen, leading to an increased focus on prevention strategies.
A growing body of evidence suggests that hospital surfaces, floors, sheets, sinks, curtains and equipment are contaminated with pathogens that can serve as sources of infection. Rigorous environmental cleaning is required to ensure that hospital surfaces, equipment, and linens are safe for patient use and to prevent transmission of such pathogens as C difficile. With the emergence of multidrug-resistant pathogens and an increasing focus on patient safety, environmental cleaning and disinfection have come to the forefront.
Hospital Surfaces
Multiple studies[2,3,4,5,6] have demonstrated contamination of hospital surfaces with epidemiologically relevant pathogens. Methicillin-resistant Staphylococcus aureus (MRSA) contamination of hospital surfaces ranges between 1% and 27% in hospital wards and can be as high as 64% in burn units, whereas vancomycin- resistant enterococcus contamination ranges between 7% and 58%.[3] Studies have also demonstrated widespread environmental contamination with C difficile in the rooms of infected patients ranging from 2.9% to 75%.[4] Multidrug-resistant gram-negative organisms, such as Escherichia coli, Klebsiella spp., Acinetobacter spp., and Pseudomonas aeruginosa, have the capacity to survive on inanimate surfaces for months, serving as reservoirs for transmission to healthcare workers and susceptible patients.[4]
High-touch surfaces are inanimate objects or surfaces in patient care areas that are handled frequently by various users, causing them to become more contaminated. The Healthcare Infection Control Practices Advisory Committee and the Centers for Disease Control and Prevention recommend disinfecting high-touch surfaces more frequently than other surfaces (Figure 1).
Figure 1. Potentially contaminated high-touch surfaces in the patient environment. Image from Wikipedia
Privacy Curtains
Hospital privacy curtains around patient beds are at high risk for cross-contamination, because they are high-touch surfaces and may not be cleaned or changed frequently. A recent pilot study[7] tracked the contamination rate of 10 freshly laundered privacy curtains in a burn unit and found that curtains in patient rooms became increasingly contaminated over time. More than 87% of curtains tested positive for MRSA by day 14. In contrast, control curtains that were not placed in patient rooms stayed clean the entire 21 days.
Hospital Bed Linens
A recent study[8] found that commercial washing machines failed to remove all traces of C difficile from hospital linens. This could possibly explain sporadic outbreaks of C difficile infections from unknown sources. In another study[9] of 15 transplant and cancer hospitals, healthcare linens were contaminated with mold upon arrival at 47% of hospitals, and failed to achieve hygienically clean standards for mold at 20% of these hospitals.
Sinks and Water Sources
Hospital water may also serve as a source of healthcare-associated infections and lead to outbreaks. Common waterborne pathogens, such as Legionellaand other gram-negative bacteria, nontuberculous mycobacteria, fungi, and viruses, may be transmitted by direct and indirect contact, ingestion, and aspiration of contaminated water, or by inhalation of aerosols from various reservoirs, such as electronic faucets (Pseudomonas aeruginosa and Legionella), decorative wall fountains (Legionella), and heater-cooler devices used in cardiac surgery (Mycobacterium chimaera).[10,11] In a recent study,[12] an Israeli hospital traced repeated infections in its intensive care unit to sink traps.
Aerosolization of bacteria during handwashing can spread these organisms in certain situations. Risk factors include clinical waste disposal in sinks, storage of materials near the sinks, and poor placement of sinks.
Healthcare Personnel Clothing
Scrubs, white lab coats, neckties, and wristwatches can all become contaminated and serve as vehicles to transfer pathogens from one patient to another.[13] In the recent Antimicrobial Scrub Contamination and Transmission (ASCOT) trial,[14] researchers followed 40 nurses who were wearing traditional cotton-polyester scrubs, scrubs with silver alloy embedded in the fabric, or scrubs treated with antibacterial materials. They took cultures from the nurses’ scrubs, the patients, and the environment (bed rails, beds, and supply carts), which showed that nurses’ scrubs frequently became contaminated with pathogens in the environment, and the type of scrubs worn made no difference.
Duodenoscopes
In 2013, the US Food and Drug Administration discovered a potential association between duodenoscopes and multidrug-resistant bacterial infections.[15] Increasing numbers of outbreaks have been reported since then, some with fatal outcomes. In a recent study[16] of 73 participating Dutch endoscopic retrograde cholangiopancreatography centers, at least one contaminated duodenoscope was identified in 39% of these facilities. Among contaminated duodenoscopes, 15% harbored microorganisms of gastrointestinal origin, suggesting failure of disinfection practices. Recent strategies have focused on improving current reprocessing and process control procedures.[17]
Blood Product Transfusions
In 2017, two separate clusters of transfusion-associated sepsis episodes were reported in Utah and California.[18] Investigations revealed no deviations in blood supplier or hospital procedures. Despite following procedures and protocols, the risk for transfusion-related infection can persist, which makes additional interventions necessary. Blood product suppliers and hospitals are now working on including pathogen inactivation, rapid detection devices, and modified screening of blood products to mitigate these risks.
What More Can Be Done to Clean the Hospital?
Until better data are available, healthcare facilities should focus on evidence-based strategies to prevent transmission, including hand hygiene, environmental cleaning, and appropriate sterilization and disinfection practices. Healthcare workers should remember the World Health Organization’s 5 Moments of Hand Hygiene: before patient contact, after patient contact, after contact with inanimate surfaces and objects (including medical equipment) in the vicinity of the patient, after contact with any body fluids or if hands are visibly soiled, and before an aseptic procedure (Figure 2).
Figure 2. Five moments for hand hygiene. Image from World Health Organization
It is important to address personnel issues in hospital environmental services departments and follow manufacturers’ recommendations for cleaning and disinfection. Monitoring of cleanliness is also important, and should be done by more than one method. Recognizing and educating the cleaning staff is equally important for the success of a cleaning program.
Currently, disinfection procedures vary significantly among hospitals, and there is no gold standard. As newer technologies, such as ultraviolet light disinfection and electronic hand-hygiene monitoring systems, become available, we should carefully assess the evidence, cost-effectiveness, and implementation challenges before investing in them.
