There is increasing interest in the role of cleaning for controlling hospital-acquired infections (HAIs). Pathogens such as meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), norovirus, multi-resistant Gram-negative bacilli and Clostridium difficile persist in the healthcare environment for considerable lengths of time. Both detergent and/or disinfectant-based cleaning can control these pathogens in routine and outbreak situations despite minimal evidence. Traditional cleaning methods are notoriously inefficient for decontamination and new approaches have been proposed, including novel disinfectants, automated dispersal systems, steam cleaning and a range of antimicrobial surfaces and coatings. These methods are difficult to evaluate because few studies have modelled environmental data against patient outcome. This means that current decontamination practices cannot be assessed for cost-effectiveness. Indeed, recent studies report the value of physical removal of soil using detergent compared with more expensive (and potentially toxic) disinfectant-based methods. Clearly more work is required on cleaning and decontamination in hospitals, particularly with escalating antimicrobial resistance. Cleaning practices should be tailored to clinical risk, location, site and hand-touch frequency, and evaluated for cost-benefit for both routine and outbreak situations. Forthcoming evidence on the role of antimicrobial surfaces will supplement infection prevention strategies for healthcare environments, including those targeting multi-drug resistant pathogens.The following section contains the definitions of cleaning and decontamination; the justification for adequate healthcare decontamination; description of methods for routine (daily) cleaning; cleaning following patient discharge; cleaning of rooms housing infected patients; cleaning during or after an infection cluster or outbreak; automated cleaning methods: benefits and disadvantages; frequency of cleaning: high risk areas vs low risk areas; cleaning and decontamination hazards for staff, patients and visitors; managerial input; monitoring of cleanliness of the healthcare environment and staff training.
2.1 Cleaning: removal of dirt, debris, grease, spillages.
2.2 Decontamination: removal of microbial dirt including pathogenic microorganisms.
2.3 Sterilisation: total eradication of all microbes from surfaces or items.
3. Why is it important to clean hospitals properly?
3.1 Justification for hospital cleaning.
The best evidence for an environmental role in pathogen transmission is provided by studies demonstrating that the risk of acquiring MRSA, VRE, Acinetobacter, Pseudomonas or C. difficile is increased if a new admission is placed in a room previously occupied by a patient colonized or infected with one of these pathogens. Such pathogens are able to survive on surfaces for days, increasing the risk of infection for patients, unless they are removed by the cleaning process. In addition, cleaning and decontamination form an important part of an outbreak control plan, although the evidence for the effect of outbreak cleaning measures is often obscured by the package of additional interventions introduced in response to the outbreak.
3.2 National cleaning standards across Europe.
4. How are hospitals cleaned?
In hospitals, environmental surfaces are cleaned, or cleaned and disinfected, on a regular basis (e.g. hourly, daily, 3 times per week); when surfaces are visibly soiled; if there are spillages; and always after patient discharge. The type and frequency of routine cleaning depends upon clinical risk, patient turnover, intensity of people-traffic and surface characteristics. All hospitals should provide a written specification of cleaning services and their delivery for all areas of the hospital, whether provided by in-house or externally contracted staff. These should be reviewed on a regular basis by cleaning supervisors, hospital managers, estates and infection control.
4.1 Physical removal of visible debris and litter.
4.2 Detergent and water for surfaces to remove visible dirt, stains, smears, grease.
4.3 Disinfectant and detergent combinations.
5. Automated cleaning methods.
While interventions aimed at improving cleaning thoroughness have shown improvements, many surfaces remain inadequately cleaned and therefore potentially contaminated. Unsurprisingly, several manufacturers are developing automated room disinfection units that demonstrate superior decontamination of environmental surfaces and objects. These systems use various products including germicidal light; hydrogen peroxide; steam; and ozone.
5.1 Hydrogen peroxide.
5.2 Ultraviolet light.
5.5 Benefits of automated systems.
5.6 Disadvantages of automated systems.
Innovative technologies obviously play a role in the environmental hygiene armamentarium, but their logistical complexity as well as costs of equipment and personnel costs make it imperative that independent, objectively controlled studies should be undertaken to clarify the true role of these technologies. Concern over the premature incorporation of these systems into routine decontamination strategies has been expressed by several authors. Cost-effectiveness studies would help aid selection from the different room decontamination systems available. Recent recommendations on innovation and research in infection control support the opportunity for hospitals to trial new cleaning and decontamination technologies and publish their findings.
6. Where are hospitals cleaned?
Frequent hand-touch sites such as door handles, taps, keyboards, telephones, light switches etc. are environmental surfaces that pose an increased risk of pathogen transmission. However, there is a wide range of sites and surfaces in the healthcare environment that requires cleaning, with or without disinfection, on a routine basis.
6.1 Hand touch sites.
6.2 Clinical equipment.
6.3 General surfaces: floors, walls, corridors, stairs.
6.4 Bathrooms, showers, baths, toilets.
6.5 Sluice; bed pan washer.
6.6 Treatment room.
6.7 Storage room & cupboards.
6.8 Ward kitchens.
6.9 High risk unit or ward; surgical theatre environment.
6.10 Clean rooms (formulation of medicinal products)
6.11 Outpatient clinics
6.13 Hospital shops, cafes and kitchens
6.14 Estates premises.
7. When are hospitals cleaned?
The type and frequency of routine cleaning depends upon clinical risk, patient turnover, intensity of people-traffic and surface characteristics. Frequent and stringent cleaning specifications are applied to areas encompassing operating theatres, intensive care units, transplant wards and so-called “clean” rooms, where sterile medications are decanted and/or processed. Hospital kitchens, restaurants and cafes also receive targeted frequent cleaning, as do the laboratories. Less comprehensive cleaning regimens are carried out for corridors and stairwells; offices and waiting rooms; selected out-patient, general purpose and entrance areas.
7.1 Routine daily cleaning e.g. all wards and clinics (spot checks, spillages or incidents may dictate additional cleaning).
7.2 Multiple daily cleaning for high risk areas e.g. critical care, special care baby unit, clean rooms, haematology and transplant units, surgical theatres, oncology wards, etc.
7.3 Discharge or terminal cleaning (routine/non-infected)
7.4 Cleaning for rooms accommodating patients with transmissible infection e.g. MRSA, Clostridium difficile, VRE, multi-drug resistant coliforms, Acinetobacter spp., norovirus, Stenotrophomonas, influenza, TB, etc.
7.6 Cleaning following building work, repairs or plumbing incidents.
7.7 Ongoing outbreak; case cluster; risk of outbreak.
8. Cleaning and decontamination hazards.
8.1 Physical hazards e.g. slips , trips, falls, repetitive strain injuries, back pain.
8.2 Toxic hazards eg. chlorine gas released for bleach products.
8.3 Contamination of cleaning fluids and equipment.
9. Antimicrobial surfaces.
Treating or coating hospital surfaces liable to contamination by pathogens could kill or inhibit microbes in order to reduce the risk of transmission to patients. Such surfaces would not necessarily obviate the need for routine cleaning but might provide a safety net for inadequate or misplaced cleaning. Self-sanitizing surfaces have the ability to supplement manual cleaning, itself dependent upon operator time, choice and ability, and thus subject to considerable variation.
9.1 Antifouling and anti-adhesive coatings.
9.2 Antimicrobial coatings.
9.2.6 Light activated.
10. Monitoring cleanliness.
10.1 Visual inspection.
10.2 Chemical assessment (ATP bioluminescence).
10.3 Microbiological screening.
10.4 Cleaning assessment framework.
11. Cleaning supervision, training and management.
11.1 Recruitment and retention of cleaning staff.
11.2 Monitoring cleaning.
11.2.1 Fluorescent markers.
11.2.2 Direct observation & supervision.
11.3 Dealing with patient complaints.
11.4 Management priorities.
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Original contribution from
Stephanie J. Dancer, Dept. of Microbiology, Hairmyres hospital, East Kilbride, Lanarkshire G75 8RG.