modeling HAI rates against arbitrary measurements of cleaning / cleanliness requires universal standards and these are not yet established .”
There is no scientific , widely accepted standard of what constitutes “ clean ” for the healthcare environment because a benchmark figure for hard-surface cleanliness is needed , she says .
“ Exceeding ( the benchmark figure ) means patients could be at high risk of HAI , and being under the benchmark means patients are at less risk of HAI ,” Dancer says . “ But to ascertain this benchmark , we need to know exactly how many patients get HAIs directly from the healthcare environment , so we can model HAI rates against tangible levels of surface soil . The problem is , when a patient is diagnosed with an HAI , we often have no idea where the pathogen came from . Was it surfaces beside the patient ? Was it air ? Was it someone ’ s hands ? Or was the patient already colonized with the pathogen ? An HAI might only have occurred because healthcare interventions allowed the colonizing organism to become a pathogen ( such as when a urinary catheter is inserted ). No amount of environmental cleaning will impact on this scenario . You can ’ t ‘ clean ’ the patient of their normal microbiome . We need to know exactly how many HAIs are transmitted to the patient after admission directly or indirectly from the contaminated healthcare environment .”
Dancer continues , “ Then you draw the curve and choose the most reliable benchmark . You can never eliminate total HAI risk from the environment , but you could reduce it through a range of hygiene interventions , including cleaning . It is a bit more complicated than this , of course , but distinguishing between endogenous and exogenous infection is the first hurdle .”
As she observes in her paper , “ When is a surface ‘ clean ’? Which level of contamination , for what surface type , in which area , ward or unit , provides assurance that there is less risk of a patient succumbing to an HAI ? This is also complicated by the fact that methods for sampling hard surfaces , culture and identification are varied , inaccurate , unreliable , necessarily expensive , time consuming and require microbiological expertise . It is also the case that surfaces may be influenced by daily application of cleaning fluids , antimicrobial surface coatings , wear and tear , and even biofilm . A set of microbiological standards encompassing generic hand-touch sites within , and outside , near-patient areas , providing a benchmark for HAI risk would be extremely helpful , not just for infection control and domestic agencies , but as an early indication of a potential outbreak .”
Dancer says that professionals in the IP & C sector have purview over the choice of a microbiological standard of “ clean ” in the healthcare setting . “ Clinical microbiologists , healthcare epidemiologists , infection prevention and control staff , and cleaners ( environmental services personnel ) are working together , to benefit their hospital ,” she remarks . “ Hospitals are all different and so are cleaning practices , let alone funding and resourcing , sampling procedures and lab practices .”
In the early 2000s , several medical organizations in the UK published standards and / or audits regarding environmental cleanliness in hospitals . However , as Dancer ( 2023 ) points out , “ Without numerical measures , evaluating the quality of hospital cleaning and cleanliness was limited . These , and other national guidelines , could only propose a range of visual indices , which do not necessarily correspond with microbiological risk .”
Dancer notes that “ Since cleaning could be a cost-effective method of controlling HAIs , it needed investigation as a scientific process with measurable outcome . To achieve this , it was thought necessary to adopt an integrated and risk-based approach , which would include preliminary visual assessment , rapid sensitive tests for organic soil and microbiological sampling . Such an approach had already been established by the food industry to manage cleaning practices in a cost-effective manner . There was also an index of microbial air contamination ( IMA ) established for healthcare environments at risk , with maximum acceptable levels for different classes of contamination . Clearly , if bioburden on hospital surfaces could be quantitated ; monitored ; and modelled against cleaning activities , staffing , occupancy and / or infection
Where We ’ ve Been , Where We Are in Environmental Hygiene
Dancer ( 2023 ) provides a quick journey through the history of healthcare environmental hygiene , including the 1974 declaration by the Committee on Infections within Hospitals of the American Hospital Association ( AHA ) that “ the occurrence of nosocomial infection has not been related to levels of microbial contamination of air , surfaces , and fomites . So that meaningful standards for permissible levels of such contamination do not exist .” ( Maki , et al . 1982 ) That same paper observed that determining the precise number of organisms present in the environment would not be a relevant measure of infection risk nor would it justify the time and expense of measurement . Years later , a comment in a whitepaper journal said that surfaces being cleaned and the frequency of cleaning and cleaning methods in hospitals were unlikely to have a major effect on the number of patients becoming infected . ( Collins , 1988 ) Hota ( 2004 ) reported it being assumed that organisms in the inanimate environment were merely “ innocent bystanders ,” rather than a source of patient colonization and infection .
As Dancer ( 2023 ) summarizes , “ So , the prevailing view during the late 20th century was that the environment was not thought to be important in HAI prevention … This view has changed over the past 20 years . Interest in hospital cleaning has gradually increased , as careful epidemiological and molecular studies have confirmed clear links between patient infections and the healthcare environment … However , there remains dissent over the extent of the environmental contribution to HAI , given that patients often suffer infections emanating from their own microbial carriage . Furthermore , the evidence base is compromised by global attitudes toward quality cleaning , which varies considerably within and between hospitals , and indeed , countries . Environmental monitoring has not generally progressed further than visual inspection , and indeed , measurable standards for surface bioburden have not yet been universally accepted . In general , cleaning practices depend upon the whim of individuals , including those in managerial positions .”
References :
Maki DG , Alvarado CJ , Hassemer CA , Zilz MA . Relation of the inanimate hospital environment to endemic nosocomial infection . N Engl J Med . 1982 ; 307 ( 25 ): 1562-6 .
Collins BJ . The hospital environment : how clean should a hospital be ? J Hosp Infect 1988 ; 11 Suppl A : 53-56 .
Hota B . Contamination , disinfection , and cross-colonization : are hospital surfaces reservoirs for nosocomial infection ? Clin Infect Dis . 2004 ; 39 ( 8 ): 1182-89 . www . healthcarehygienemagazine . com • september 2023
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