Examining the association between surface bioburden and frequently touched sites in intensive care

Assessing the impact of a cleaning programme on environmental hygiene in labour and neonatal wards: an exploratory study in The Gambia

BACKGROUND

Effective surface cleaning in hospitals is crucial to prevent the transmission of pathogens. However, hospitals in low- and middle-income countries face cleaning challenges due to limited resources and inadequate training.

METHODS

We assessed the effectiveness of a modified TEACH CLEAN programme for trainers in reducing surface microbiological contamination in the newborn unit of a tertiary referral hospital in The Gambia. We utilised a quasi-experimental design and compared data against those from the labour ward. Direct observations of cleaning practices and key informant interviews were also conducted to clarify the programme's impact.

RESULTS

Between July and September 2021 (pre-intervention) and October and December 2021 (post-intervention), weekly surface sampling was performed in the newborn unit and labour ward. The training package was delivered in October 2021, after which their surface microbiological contamination deteriorated in both clinical settings. While some cleaning standards improved, critical aspects such as using fresh cleaning cloths and the one-swipe method did not. Interviews with senior departmental and hospital management staff revealed ongoing challenges in the health system that hindered the ability to improve cleaning practices, including COVID-19, understaffing, disruptions to water supply and shortages of cleaning materials.

CONCLUSIONS

Keeping a hospital clean is fundamental to good care, but training hospital cleaning staff in this low-income country neonatal unit failed to reduce surface contamination levels. Further qualitative investigation revealed multiple external factors that challenged any possible impact of the cleaning programme. Further work is needed to address barriers to hospital cleaning in low-income hospitals.

An automated contact model for transmission of dry surface biofilms of Acinetobacter baumannii in healthcare

BACKGROUND

Dry surface biofilms (DSBs) have been recognized across environmental and equipment surfaces in hospitals and could explain how microbial contamination can survive for an extended period and may play a key role in the transmission of hospital-acquired infections. Despite little being known on how they form and proliferate in clinical settings, DSB models for disinfectant efficacy testing exist.

AIM

In this study we develop a novel biofilm model to represent formation within hospitals, by emulating patient to surface interactions.

METHODS

The model generates a DSB through the transmission of artificial human sweat (AHS) and clinically relevant pathogens using a synthetic thumb capable of emulating human contact. The DNA, glycoconjugates and protein composition of the model biofilm, along with structural features of the micro-colonies was determined using fluorescent stains visualized by epifluorescence microscopy and compared with published clinical data.

RESULTS

Micrographs revealed the heterogeneity of the biofilm across the surface; and reveal protein as the principal component within the matrix, followed by glycoconjugates and DNA. The model repeatably transferred trace amounts of micro-organisms and AHS, every 5 min for up to 120 h on to stainless-steel coupons to generate a biofilm model averaging 1.16 × 103 cfu/cm2 falling within the reported range for clinical DSB (4.20 × 102 to 1.60 × 107 bacteria/cm2).

CONCLUSION

Our in vitro DSB model exhibits many phenotypical characteristics and traits to those reported in situ. The model highlights key features often overlooked and the potential for downstream applications such as antibiofilm claims using more realistic microbial challenges.

Hospital cleaning: past, present, and future

INTRODUCTION

The importance of hospital cleaning for controlling healthcare-associated infection (HAI) has taken years to acknowledge. This is mainly because the removal of dirt is inextricably entwined with gender and social status, along with lack of evidence and confusion over HAI definitions. Reducing so-called endogenous infection due to human carriage entails patient screening, decolonisation and/or prophylaxis, whereas adequate ventilation, plumbing and cleaning are needed to reduce exogenous infection. These infection types remain difficult to separate and quantitate. Patients themselves demonstrate wide-ranging vulnerability to infection, which further complicates attempted ranking of control interventions, including cleaning. There has been disproportionate attention towards endogenous infection with less interest in managing environmental reservoirs.

QUANTIFYING CLEANING AND CLEANLINESS

Finding evidence for cleaning is compromised by the fact that modelling HAI rates against arbitrary measurements of cleaning/cleanliness requires universal standards and these are not yet established. Furthermore, the distinction between cleaning (soil removal) and cleanliness (soil remaining) is usually overlooked. Tangible bench marking for both cleaning methods and all surface types within different units, with modification according to patient status, would be invaluable for domestic planning, monitoring and specification.

AIMS AND OBJECTIVES

This narrative review will focus on recent history and current status of cleaning in hospitals. While its importance is now generally accepted, cleaning practices still need attention in order to determine how, when and where to clean. Renewed interest in removal and monitoring of surface bioburden would help to embed risk-based practice in hospitals across the world.

Human microbiome transfer in the built environment differs based on occupants, objects, and buildings

Compared to microbiomes on other skin sites, the bacterial microbiome of the human hand has been found to have greater variability across time. To increase understanding regarding the longitudinal transfer of the hand microbiome to objects in the built environment, and vice versa, 22 participants provided skin microbiome samples from their dominant hands, as well as from frequently and infrequently touched objects in their office environments. Additional longitudinal samples from home environments were obtained from a subset of 11 participants. We observed stability of the microbiomes of both the hand and built environments within the office and home settings; however, differences in the microbial communities were detected across the two built environments. Occupants' frequency of touching an object correlated to that object having a higher relative abundance of human microbes, yet the percent of shared microbes was variable by participants. Finally, objects that were horizontal surfaces in the built environment had higher microbial diversity as compared to objects and the occupants' hands. This study adds to the existing knowledge of microbiomes of the built environment, enables more detailed studies of indoor microbial transfer, and contributes to future models and building interventions to reduce negative outcomes and improve health and well-being.

Interlaboratory reproducibility of a touch-transfer assay for the assessment of antimicrobial surfaces

BACKGROUND

Various assay methods have been developed to study antimicrobial activity based on contamination of surfaces with different amounts of liquid bacterial suspensions. Since surfaces with frequent hand contact are typically touched in a dry state in clinical settings, these tests may be inappropriate at assessing effectiveness to reduce pathogen transmission.

AIM

To investigate a surface previously confirmed to display antimicrobial activity even after drying of small volumes of bacterial suspension (Egger antimicrobial surfaces: EAS) under conditions modelling dry contamination using a touch-transfer method.

METHODS

EAS, an antimicrobial copper alloy, as well as a negative control were examined to assess interlaboratory test reproducibility.

FINDINGS

Significantly fewer bacteria on EAS after touch transfer and some differences in the touch transmission were detected between the two laboratories. However, an identical assessment of effectiveness for EAS came from both laboratories. Interestingly, despite previously detected antimicrobial efficacy of EAS and the antimicrobial copper alloy after liquid contamination, insufficient activity was observed under dry conditions during a contact time of 4 h by both laboratories. Experiments under standardized air humidity in one laboratory revealed at least for copper a strong influence of humidity on antimicrobial activity. These data indicate that procedures involving contamination of surfaces with organisms suspended in liquids are not directly comparable to dry contamination.

CONCLUSION

Since, in the real world of a hospital, organisms are typically transferred between dry surfaces, further standardization of the touch-transfer method is worthwhile for a better understanding of the efficacy of such surfaces.

Evaluating the environmental microbiota across four National Health Service hospitals within England

Hospital surfaces contaminated with microbial soiling, such as dry surface biofilms (DSBs), can act as a reservoir for pathogenic micro-organisms, and inhibit their detection and removal during routine cleaning. Studies have recognized that such increases in bioburden can hinder the impact of disinfectants and mask the detection of potential pathogens. Cleanliness within healthcare settings is often determined through routine culture-based analysis, whereby surfaces that exhibit >2.5 colony-forming units (CFU) per cm² pose a risk to patient health; therefore, any underestimation could have detrimental effects. This study quantified microbial growth on high-touch surfaces in four hospitals in England over 19 months. This was achieved using environmental swabs to sample a variety of surfaces within close proximity of the patient, and plating these on to non-specific low nutrient detection agar. The presence of DSBs on surfaces physically removed from the environment was confirmed using real-time imaging through episcopic differential interference contrast microscopy combined with epifluorescence. Approximately two-thirds of surfaces tested exceeded the limit for cleanliness (median 2230 CFU/cm²), whilst 83% of surfaces imaged with BacLight LIVE/DEAD staining confirmed traces of biofilm. Differences in infection control methods, such as choice of surface disinfectants and cleaning personnel, were not reflected in the microbial variation observed and resulting risk to patients. This highlights a potential limitation in the effectiveness of the current standards for all hospital cleaning, and further development using representative clinical data is required to overcome this limitation.

Exploring spatial averaging of contamination in fomite microbial transfer models and implications for dose

BACKGROUND

When modeling exposures from contact with fomites, there are many choices in defining the sizes of compartments representing environmental surfaces and hands, and the portions of compartments involved in contacts. These choices impact dose estimates, yet there is limited guidance for selection of these model parameters.

OBJECTIVE

The study objective was to explore methods for representing environmental surface and hand contact areas in exposure models and implications for estimated doses.

METHODS

A simple scenario was used: an individual using their hands to contact their face and two microbially contaminated environmental surfaces. Four models were developed to explore different compartmentalization strategies: (1) hands and environmental surfaces each represented by one compartment, (2) hands represented by two compartments (fingertips vs. non-fingertip areas) while environmental surfaces were represented by one compartment, (3) hands represented by a single compartment and environmental surfaces represented by two compartments, and (4) hands and environmental surfaces each represented by two compartments. Sensitivity analyses were conducted to evaluate the influence of heterogeneous surface contact frequency, hand contact type, and hand dominance on dose.

RESULTS

Estimated doses were greatest when hand areas and environmental surfaces were each represented by two compartments, indicating that surface area "dilutes" contaminant concentration and decreases estimated dose.

SIGNIFICANCE

Model compartment designations for hands and environmental surfaces affect dose estimation, but more human behavior data are needed.

IMPACT STATEMENT

A common problem for exposure models describing exposures via hand-to-surface contacts occurs in the way that estimated contamination across human skin (usually hands) or across environmental surfaces is spatially averaged, as opposed to accounting for concentration changes across specific parts of the hand or individual surfaces. This can lead to the dilution of estimated contaminants and biases in estimated doses in risk assessments. The magnitude of these biases and implications for the accuracy in risk assessments are unknown. We quantify differences in dose for various strategies of compartmentalizing environmental surfaces and hands to inform guidance on future exposure model development.

Bacterial Cross-Transmission between Inanimate Surfaces and Patients in Intensive Care Units under Real-World Conditions: A Repeated Cross-Sectional Study

Background/Objectives: Contaminated surfaces play an important role in the nosocomial infection of patients in intensive care units (ICUs). This study, conducted in two ICUs at Edouard Herriot Hospital (Lyon, France), aimed to describe rooms' microbial ecology and explore the potential link between environmental contamination and patients' colonization and/or infection. Methods: Environmental samples were realized once monthly from January 2020 to December 2021 on surfaces close to the patient (bedrails, bedside table, and dedicated stethoscope) and healthcare workers' high-touch surfaces, which were distant from the patient (computer, worktop/nurse cart, washbasin, and hydro-alcoholic solution/soap dispenser). Environmental bacteria were compared to the cultures of the patients hospitalized in the sampled room over a period of ± 10 days from the environmental sampling. Results: Overall, 137 samples were collected: 90.7% of the samples close to patients, and 87.9% of the distant ones were positives. Overall, 223 bacteria were isolated, mainly: Enterococcus faecalis (15.7%), Pantoea agglomerans (8.1%), Enterobacter cloacae/asburiae (6.3%), Bacillus cereus and other Bacillus spp (6.3%), Enterococcusfaecium (5.8%), Stenotrophomonas maltophilia (5.4%), and Acinetobacter baumannii (4.9%). Throughout the study, 142 patients were included, of which, n = 67 (47.2%) were infected or colonized by at least one bacterium. In fourteen cases, the same bacterial species were found both in environment and patient samples, with the suspicion of a cross-contamination between the patient-environment (n = 10) and environment-patient (n = 4). Conclusions: In this work, we found a high level of bacterial contamination on ICU rooms' surfaces and described several cases of potential cross-contamination between environment and patients in real-world conditions.

Effectiveness Of The Bicinchoninic Acid Method In Patient Unit Cleaning In Intensive Care

Objective: This study was conducted to identify the effectiveness of the Bicinchoninic Acid/(BCA) method applied for evaluate the cleaning the beds of the patients with infections or colonization requiring strict contact isolation after discharge. Methods: This is an experimental study and it was used the ORION checklist. In this study, 480 BCA and 480 microbiological samples were taken from 40 patient units before and after cleaning and the results were compared. The cleaning procedure was evaluated by examining whether there was post-cleaning gel residue in the areas stained with fluorescent gel before the cleaning. Results: When post-cleaning BCA and post-cleaning microbiological sampling data were compared, no statistical difference was found. When the data of the areas stained with fluorescent gel before and after the cleaning were compared, it was observed that there was a statistical difference. It was revealed that the bedside and the bed controller were mostly contaminated in both methods. Conclusions: It was concluded that BCA was an effective method that could be used to evaluate the cleaning applied to the infected patient unit. It is thought that cleaning only areas that are considered to be contaminated after evaluating the cleaning with an effective method will prevent contamination due to cleaning and will provide more positive results in terms of time, labor, and cost. The control of cleanliness using objective methods can help maintain a safe environment. This study is registered to ClinicalTrials.gov with the number ID:NCT04212130.

A Better Disinfectant for Low-Resourced Hospitals? A Multi-Period Cluster Randomised Trial Comparing Hypochlorous Acid with Sodium Hypochlorite in Nigerian Hospitals: The EWASH Trial

Environmental hygiene in hospitals is a major challenge worldwide. Low-resourced hospitals in African countries continue to rely on sodium hypochlorite (NaOCl) as major disinfectant. However, NaOCl has several limitations such as the need for daily dilution, irritation, and corrosion. Hypochlorous acid (HOCl) is an innovative surface disinfectant produced by saline electrolysis with a much higher safety profile. We assessed non-inferiority of HOCl against standard NaOCl for surface disinfection in two hospitals in Abuja, Nigeria using a double-blind multi-period randomised cross-over study. Microbiological cleanliness [Aerobic Colony Counts (ACC)] was measured using dipslides. We aggregated data at the cluster-period level and fitted a linear regression. Microbiological cleanliness was high for both disinfectant (84.8% HOCl; 87.3% NaOCl). No evidence of a significant difference between the two products was found (RD = 2%, 90%CI: -5.1%-+0.4%; p-value = 0.163). We cannot rule out the possibility of HOCl being inferior by up to 5.1 percentage points and hence we did not strictly meet the non-inferiority margin we set ourselves. However, even a maximum difference of 5.1% in favour of sodium hypochlorite would not suggest there is a clinically relevant difference between the two products. We demonstrated that HOCl and NaOCl have a similar efficacy in achieving microbiological cleanliness, with HOCl acting at a lower concentration. With a better safety profile, and potential applicability across many healthcare uses, HOCl provides an attractive and potentially cost-efficient alternative to sodium hypochlorite in low resource settings.

Artificial Human Sweat as a Novel Growth Condition for Clinically Relevant Pathogens on Hospital Surfaces

The emergence of biofilms on dry hospital surfaces has led to the development of numerous models designed to challenge the efficacious properties of common antimicrobial agents used in cleaning. This is in spite of limited research defining how dry surfaces are able to facilitate biofilm growth and formation in such desiccating and nutrient-deprived environments. While it is well established that the phenotypical response of biofilms is dependent on the conditions in which they are formed, most models incorporate a nutrient-enriched, hydrated environment dissimilar to the clinical setting. In this study, we piloted a novel culture medium, artificial human sweat (AHS), which is perceived to be more indicative of the nutrient sources available on hospital surfaces, particularly those in close proximity to patients. AHS was capable of sustaining the proliferation of four clinically relevant multidrug-resistant pathogens (Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa) and achieved biofilm formation at concentration levels equivalent to those found in situ (average, 6.00 log₁₀ CFU/cm²) with similar visual characteristics upon microscopy. The AHS model presented here could be used for downstream applications, including efficacy testing of hospital cleaning products, due to its resemblance to clinical biofilms on dry surfaces. This may contribute to a better understanding of the true impact these products have on surface hygiene. IMPORTANCE Precise modeling of dry surface biofilms in hospitals is critical for understanding their role in hospital-acquired infection transmission and surface contamination. Using a representative culture condition which includes a nutrient source is key to developing a phenotypically accurate biofilm community. This will enable accurate laboratory testing of cleaning products and their efficacy against dry surface biofilms.

What is the risk of acquiring SARS-CoV-2 from the use of public toilets?

Public toilets and bathrooms may act as a contact hub point where community transmission of SARS-CoV-2 occurs between users. The mechanism of spread would arise through three mechanisms: inhalation of faecal and/or urinary aerosol from an individual shedding SARS-CoV-2; airborne transmission of respiratory aerosols between users face-to-face or during short periods after use; or from fomite transmission via frequent touch sites such as door handles, sink taps, lota or toilet roll dispenser. In this respect toilets could present a risk comparable with other high throughput enclosed spaces such as public transport and food retail outlets. They are often compact, inadequately ventilated, heavily used and subject to maintenance and cleaning issues. Factors such as these would compound the risks generated by toilet users incubating or symptomatic with SARS-CoV-2. Furthermore, toilets are important public infrastructure since they are vital for the maintenance of accessible, sustainable and comfortable urban spaces. Given the lack of studies on transmission through use of public toilets, comprehensive risk assessment relies upon the compilation of evidence gathered from parallel studies, including work performed in hospitals and prior work on related viruses. This narrative review examines the evidence suggestive of transmission risk through use of public toilets and concludes that such a risk cannot be lightly disregarded. A range of mitigating actions are suggested for both users of public toilets and those that are responsible for their design, maintenance and management.

Microbial burden on environmental surfaces in patient rooms before daily cleaning-Analysis of multiple confounding variables

OBJECTIVES

Estimated levels of microbial burden on hospital environmental surfaces vary substantially among published studies. Cultures obtained during a cluster-controlled crossover trial of a quaternary ammonium (Quat) disinfectant versus an improved hydrogen peroxide (IHP) disinfectant provided additional data on the amount of microbial burden on selected surfaces.

METHODS

RODAC plates containing D/E neutralizing agar were used to sample a convenience sample of 5-8 high-touch surfaces in patient rooms on 2 medical wards, an intensive care unit, and a step-down unit at a large hospital. Before routine daily cleaning, samples were obtained in varying rooms over an 11-month period. RODAC plates (1 per surface sampled) were incubated for 72 hours, and aerobic colony counts per plate (ACCs) were determined. Statistical analysis was used to determine the potential impact on ACCs of study period, cleaning compliance rate, disinfectant used, ward, surface sampled, and isolation room status.

RESULTS

Overall, 590 cultures were obtained on Quat wards and 589 on IHP wards. Multivariable regression analysis revealed that mean ACCs differed significantly by site (P < .001), type of ward (P < .001), isolation room status (P = .039), and study period (P = .036). The highest mean ACCs per RODAC plate were on toilet seats (112.8), bedside rails (92.0), and bathroom grab bars (79.5).

CONCLUSIONS

The combination of factors analyzed revealed that estimating microbial burden is complex and is affected by multiple factors. Additional studies should evaluate individual sites, ward types, cleaning and disinfection practices, and isolation room status.

Respirators, face masks, and their risk reductions via multiple transmission routes for first responders within an ambulance

First responders may have high SARS-CoV-2 infection risks due to working with potentially infected patients in enclosed spaces. The study objective was to estimate infection risks per transport for first responders and quantify how first responder use of N95 respirators and patient use of cloth masks can reduce these risks. A model was developed for two Scenarios: an ambulance transport with a patient actively emitting a virus in small aerosols that could lead to airborne transmission (Scenario 1) and a subsequent transport with the same respirator or mask use conditions, an uninfected patient; and remaining airborne SARS-CoV-2 and contaminated surfaces due to aerosol deposition from the previous transport (Scenario 2). A compartmental Monte Carlo simulation model was used to estimate the dispersion and deposition of SARS-CoV-2 and subsequent infection risks for first responders, accounting for variability and uncertainty in input parameters (i.e., transport duration, transfer efficiencies, SARS-CoV-2 emission rates from infected patients, etc.). Infection risk distributions and changes in concentration on hands and surfaces over time were estimated across sub-Scenarios of first responder respirator use and patient cloth mask use. For Scenario 1, predicted mean infection risks were reduced by 69%, 48%, and 85% from a baseline risk (no respirators or face masks used) of 2.9 × 10-2 ± 3.4 × 10-2 when simulated first responders wore respirators, the patient wore a cloth mask, and when first responders and the patient wore respirators or a cloth mask, respectively. For Scenario 2, infection risk reductions for these same Scenarios were 69%, 50%, and 85%, respectively (baseline risk of 7.2 × 10-3 ± 1.0 × 10-2). While aerosol transmission routes contributed more to viral dose in Scenario 1, our simulations demonstrate the ability of face masks worn by patients to additionally reduce surface transmission by reducing viral deposition on surfaces. Based on these simulations, we recommend the patient wear a face mask and first responders wear respirators, when possible, and disinfection should prioritize high use equipment.

Characteristics of hand-to-environment contact during indoor activities in daily life among Korean adults using a video-based observation method

Objectives

The aim of this study was to describe the characteristics of hand-to-environmental contact (HEC) and to identify the factors influencing HEC behavior in Korean adults’ indoor daily life.

Methods

Thirty participants were enrolled from January 14 to February 12, 2018 after providing informed consent for being videotaped. Data were collected by recording their indoor daily lives for 2 hours, resulting in 4,732 HEC cases. To ensure the accuracy and reliability of the HEC readings, 3 training sessions were conducted for the videotape readers. Rereading and verifying randomly selected data ensured the validity of intra- and inter-reader readings.

Results

The most frequent contact items were phones, papers, computer accessories, and furniture surfaces. The contact density (frequency-duration/min) was highest for category II (items occasionally shared by others, 56.8), followed in descending order by category I (items for individual use, 35.9), and category III (public use items, 3.4). Significant differences in contact density were found according to participants’ demographic characteristics.

Conclusion

As mobile phones were the most frequent contact item, regular and strict mobile phone cleansing or disinfection strategies are needed, in addition to preventative measures taken for category II and III items. Avoiding sharing personal items with others, refraining from unnecessary HEC, and maintaining strict hand hygiene are recommended.

Nondetection of SARS-CoV-2 on high-touch surfaces of public areas next to COVID-19 hospitalization units

We studied the contamination with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the bacterial load of high-touch surfaces located in public areas next to coronavirus disease (COVID-19) hospitalization units. Ninety-two samples were obtained from 46 different high-touch surfaces: 36 sites next to COVID-19 hospitalization units and 10 sites in the cabins of the public elevators. SARS-CoV-2 was not detected at any site, despite high bacterial loads suggested that the studied sites had been frequently touched prior to the sampling.

Practical recommendations for routine cleaning and disinfection procedures in healthcare institutions: a narrative review

Healthcare-associated infections (HAIs) are the most common adverse outcomes due to delivery of medical care. HAIs increase morbidity and mortality, prolong hospital stay, and are associated with additional healthcare costs. Contaminated surfaces, particularly those that are touched frequently, act as reservoirs for pathogens and contribute towards pathogen transmission. Therefore, healthcare hygiene requires a comprehensive approach whereby different strategies may be implemented together, next to targeted, risk-based approaches, in order to reduce the risk of HAIs for patients. This approach includes hand hygiene in conjunction with environmental cleaning and disinfection of surfaces and clinical equipment. This review focuses on routine environmental cleaning and disinfection including areas with a moderate risk of contamination, such as general wards. As scientific evidence has not yet resulted in universally accepted guidelines nor led to universally accepted practical recommendations pertaining to surface cleaning and disinfection, this review provides expert guidance for healthcare workers in their daily practice. It also covers outbreak situations and suggests practical guidance for clinically relevant pathogens. Key elements of environmental cleaning and disinfection, including a fundamental clinical risk assessment, choice of appropriate disinfectants and cleaning equipment, definitions for standardized cleaning processes and the relevance of structured training, are reviewed in detail with a focus on practical topics and implementation.

Evaluation of the Effectiveness of Two Automated Room Decontamination Devices Under Real-Life Conditions

To evaluate the effectiveness of automated room decontamination devices, a common aerosolized hydrogen peroxide (aHP) as well as a recent gaseous ozone-based device, which produces the disinfectant reagent without the need of consumables, were tested under real-life conditions. Twenty-two contaminated surfaces were positioned in different areas in a patient room with adjacent bathroom and anteroom. Following the decontamination process bacteria were recovered and reduction factors were calculated after performing quantitative culture. Following the manufactures instructions, the ozone-based device displayed a bactericidal effect (log10 > 5), whereas the aHP system failed for a high bacterial burden and achieves only a complete elimination of a realistic bioburden (log10 2). After increasing the exposure time to 30 min, the aHP device also reached a bactericidal effect. Nevertheless, our results indicate, that further research and development is necessary, to get knowledge about toxicity, efficacy and safety by using in complex hospital conditions and achieve meaningful integration in cleaning procedures, to reach positive effects on disinfection performance.

Reducing Spread of Infections with a Photocatalytic Reactor-Potential Applications in Control of Hospital Staphylococcus aureus and Clostridioides difficile Infections and Inactivation of RNA Viruses

Contaminated surfaces and indoor environments are important sources of infectious spread within hospital and non-hospital facilities. Bacterial infections such as infections with Clostridioides (formerly Clostridium) difficile (C. difficile) and Staphylococcus aureus (S. aureus) and its antibiotic resistant strains continue to pose a significant risk to healthcare workers and patients. Additionally, the recent emergence of the coronavirus disease 2019 (COVID-19) pandemic, which is caused by the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlights the need for safe and effective methods to decontaminate surfaces to control infection spread in hospitals and the community. To address these critical needs, we tested a photocatalytic reactor decontamination method to disinfect contaminated surfaces in a hospital and a laboratory setting. By placing the reactor in a test hospital room, growth of S. aureus and C. difficile were significantly reduced compared with a control room. Additionally, using a model enveloped positive-sense single-stranded RNA virus, dengue virus type 2 (DENV2), we showed that the use of the photocatalytic reactor reduces viral infectivity. Collectively, the results demonstrate the potential utility of photocatalytic reactors in reducing the spread of highly contagious bacterial and viral infections through contaminated surfaces and environments.

The Clean pilot study: evaluation of an environmental hygiene intervention bundle in three Tanzanian hospitals

BACKGROUND

Healthcare associated infections (HAI) are estimated to affect up to 15% of hospital inpatients in low-income countries (LICs). A critical but often neglected aspect of HAI prevention is basic environmental hygiene, particularly surface cleaning and linen management. TEACH CLEAN is an educational intervention aimed at improving environmental hygiene. We evaluated the effectiveness of this intervention in a pilot study in three high-volume maternity and newborn units in Dar es Salaam, Tanzania.

METHODS

This study design prospectively evaluated the intervention as a whole, and offered a before-and-after comparison of the impact of the main training. We measured changes in microbiological cleanliness [Aerobic Colony Counts (ACC) and presence of Staphylococcus aureus] using dipslides, and physical cleaning action using gel dots. These were analysed with descriptive statistics and logistic regression models. We used qualitative (focus group discussions, in-depth interviews, and semi-structured observation) and quantitative (observation checklist) tools to measure why and how the intervention worked. We describe these findings across the themes of adaptation, fidelity, dose, reach and context.

RESULTS

Microbiological cleanliness improved during the study period (ACC pre-training: 19%; post-training: 41%). The odds of cleanliness increased on average by 1.33 weekly during the pre-training period (CI = 1.11-1.60), and by 1.08 (CI = 1.03-1.13) during the post-training period. Cleaning action improved only in the pre-training period. Detection of S. aureus on hospital surfaces did not change substantially. The intervention was well received and considered feasible in this context. The major pitfalls in the implementation were the limited number of training sessions at the hospital level and the lack of supportive supervision. A systems barrier to implementation was lack of regular cleaning supplies.

CONCLUSIONS

The evaluation suggests that improvements in microbiological cleanliness are possible using this intervention and can be sustained. Improved microbiological cleanliness is a key step on the pathway to infection prevention in hospitals. Future research should assess whether this bundle is cost-effective in reducing bacterial and viral transmission and infection using a rigorous study design.

Impact of a dry inoculum deposition on the efficacy of copper-based antimicrobial surfaces

BACKGROUND

The introduction of antimicrobial surfaces into healthcare environments is believed to impact positively on the rate of healthcare-associated infections by significantly decreasing pathogen presence on surfaces.

AIM

To report on a novel efficacy test that uses a dry bacterial inoculum to measure the microbicidal efficacy of antimicrobial surfaces.

METHODS

An aerosolized dry inoculum of Staphylococcus aureus or Acinetobacter baumannii was deposited on copper alloy surfaces or a hospital-grade stainless-steel surface. Surviving bacteria were enumerated following incubation of the inoculated surfaces at an environmentally relevant temperature and relative humidity. Damage caused to bacteria by the aerosolization process and by the different surfaces was investigated.

FINDINGS

Dry inoculum testing showed a <2-log₁₀ reduction in S. aureus or A. baumannii on the copper alloy surfaces tested after 24 h at 20°C and 40% relative humidity. Potential mechanisms of action included membrane damage, DNA damage and arrested cellular respiration. The aerosolization process caused some damage to bacterial cells. Once this effect was taken into account, the antimicrobial activity of copper surfaces was evident.

CONCLUSIONS

Our test provided a realistic deposition of a bacterial inoculum to a surface and, as such, a realistic protocol to assess the efficacy of dry antimicrobial environmental surfaces in vitro.

Influence of ventilation use and occupant behaviour on surface microorganisms in contemporary social housing

In the context of increasingly airtight homes, there is currently little known about the type and diversity of microorganisms in the home, or factors that could affect their abundance, diversity and nature. In this study, we examined the type and prevalence of cultivable microorganisms at eight different sites in 100 homes of older adults located in Glasgow, Scotland. The microbiological sampling was undertaken alongside a household survey that collated information on household demographics, occupant behaviour, building characteristics, antibiotic use and general health information. Each of the sampled sites revealed its own distinct microbiological character, in both species and number of cultivable microbes. While some potential human pathogens were identified, none were found to be multidrug resistant. We examined whether the variability in bacterial communities could be attributed to differences in building characteristics, occupant behaviour or household factors. Sampled sites furnished specific microbiological characteristics which reflected room function and touch frequency. We found that homes that reported opening windows more often were strongly associated with lower numbers of Gram-negative organisms at indoor sites (p < 0.0001). This work offers one of the first detailed analysis of cultivable microbes in homes of older adults and their relationship with building and occupancy related factors, in a UK context.

Surface sampling within a pediatric ward-how multiple factors affect cleaning efficacy

BACKGROUND

The objectives of this study were to assess the number of organisms present on different surfaces within a clinical environment before and after cleaning took place, and to identify the impact of cleaning. The study involved extensive 2-week microbiological environmental monitoring of an entire ward before and after cleaning; the ward was located within a pediatric hematology-oncology ward comprised of a day unit and outpatient ward.

METHODS

Tryptone soya agar contact plates were used to take a total of 1,160 surface samples before and after cleaning from 55 predetermined sites. Samples were taken from representative surfaces throughout the ward representing a variety of materials, surface heights, functions, and distances from patients, as well as both high-touch and infrequently touched surfaces.

RESULTS

After surface cleaning was undertaken within the ward, there was a significant difference between the amount of colony-forming units (CFUs) recovered before and after cleaning (P < .0001). Cleaning produced an average CFU reduction of 68% throughout the ward environment. The corridor was the most contaminated area within the ward. There were differences in the CFUs among the various areas within the ward, which were cleaned with varying efficiency. The surface material, who interacted with the surface, levels of initial contamination, perceived risk, and perceived cleanability were all found to have a varying impact on the cleaning effectiveness.

CONCLUSIONS

To the authors' current knowledge, this is the only study to assess cleaning within a pediatric ward by taking samples directly before and after cleaning. The standard of cleaning undertaken within the ward is open for discussion, and these data highlight the need for an improved cleaning intervention and can provide insight into the multitude of factors that must be considered when designing an effective training protocol.

Monitoring the effectiveness of daily cleaning practices in an intensive care unit (ICU) setting using an adenosine triphosphate (ATP) bioluminescence assay

BACKGROUND

The degree to which daily intensive care unit (ICU) cleaning practices impacts bacterial burden is controversial. The study aimed to assess the utility of using adenosine triphosphate (ATP) bioluminescence assays for monitoring effectiveness of daily cleaning in ICU environments.

METHODS

We sampled 364 total samples from 57 patient rooms and 18 common areas in 3 medical ICUs over 12 weeks, before and after routine daily cleaning. Endpoints were ATP levels (relative light units, RLU) and bacterial bioburden (colony forming units, CFU).

RESULTS

High-touch surfaces in ICU patient rooms and common areas were contaminated before and after cleaning. Routine cleaning significantly reduced bacterial burden in patient rooms (0.14 log₁₀ CFU reduction, P = .008; 0.21 log₁₀ RLU reduction, P < .001) and in ICU common areas (1.18 log₁₀ CFU reduction, P < .001; 0.72 log₁₀ RLU reduction, P < .001). Among sites with colony counts >20 CFUs, the proportion of sites with ATP readings >250 RLU was significantly higher than those with ATP readings ≤250 RLU (90.0% vs 10.0%, P < .05).

CONCLUSION

Routine cleaning significantly reduced bacterial burden on ICU environment surfaces. Although not an alternative to culture methods, ATP assays may be a useful technique to provide rapid feedback on surface cleanliness in ICU settings.

Dynamic Transmission of Staphylococcus Aureus in the Intensive Care Unit

Staphylococcus aureus is an important bacterial pathogen. This study utilized known staphylococcal epidemiology to track S. aureus between patients, surfaces, staff hands and air in a ten-bed intensive care unit (ICU).

METHODS

Patients, air and surfaces were screened for total colony counts and S. aureus using dipslides, settle plates and an MAS-100 slit-sampler once a month for 10 months. Data were modelled against proposed standards for air and surfaces, and ICU-acquired staphylococcal infection. Whole-cell genomic typing (WGS) demonstrated possible transmission pathways between reservoirs.

RESULTS

Frequently touched sites were more likely to be contaminated (>12 cfu/cm2; p = 0.08). Overall, 235 of 500 (47%) sites failed the surface standard (≤2.5 cfu/cm2); 20 of 40 (50%) passive air samples failed the "Index of Microbial Air" standard (2 cfu/9 cm plate/h), and 15/40 (37.5%) air samples failed the air standard (<10 cfu/m3). Settle plate data were closer to surface counts than automated air data; the surface count most likely to reflect pass/fail rates for air was 5 cfu/cm2. Surface counts/bed were associated with staphylococcal infection rates (p = 0.012). Of 34 pairs of indistinguishable S. aureus, 20 (59%) showed autogenous transmission, with another four (12%) occurring between patients. Four (12%) pairs linked patients with hand-touch sites and six (18%) linked airborne S. aureus, staff hands and hand-touch sites.

CONCLUSION

Most ICU-acquired S. aureus infection is autogenous, while staff hands and air were rarely implicated in onward transmission. Settle plates could potentially be used for routine environmental screening. ICU staphylococcal infection is best served by admission screening, systematic cleaning and hand hygiene.

Measuring environmental contamination in critical care using dilute hydrogen peroxide (DHP) technology: An observational cross-over study

BACKGROUND

The environment has an important role in the transmission of healthcare associated infections. This has encouraged interest in novel methods to improve hygiene in hospitals. One such technology is the use of hydrogen peroxide to decontaminate rooms and equipment; there are, however, few studies that have investigated the effect of continuous dilute hydrogen peroxide (DHP) in the clinical environment. The aim of this study was to examine the use of dilute hydrogen peroxide (DHP) in a critical care unit and measure the microbiological impact on surface contamination.

METHODS

We conducted a prospective observational cross-over study in a ten-bed critical care unit in one rural Australian hospital. Selected high-touch sites were screened using dipslides across three study phases: baseline; continuous DHP; and no DHP (control). Quantitative aerobic colony counts (ACC) were assessed against a benchmark standard of ACC >2.5 cfu/cm² to indicate hygiene failure.

RESULTS

There were low levels of microbial contamination in the unit for baseline; DHP; and no DHP phases: 2.2% (95% CI 0.7-5.4%) vs 7.7% (95% CI 4.3-13.0%) vs 6% (95% CI 3.2-10.4%) hygiene failures, respectively. Significant reduction in ACCs did not occur when the DHP was operating compared with baseline and control phases.

CONCLUSION

Further work is needed to determine whether continuous DHP technology has a role in decontamination for healthcare settings.

Quantifying the relative impact of contact heterogeneity on MRSA transmission in ICUs - a modelling study

Background

An efficient surface cleaning strategy would first target cleaning to surfaces that make large contributions to the risk of infections.

Methods

In this study, we used data from the literature about methicillin-resistant Staphylococcus aureus (MRSA) and developed an ordinary differential equations based mathematical model to quantify the impact of contact heterogeneity on MRSA transmission in a hypothetical 6-bed intensive care unit (ICU). The susceptible patients are divided into two types, these who are cared by the same nurse as the MRSA infected patient (Type 1) and these who are not (Type 2).

Results

The results showed that the mean MRSA concentration on three kinds of susceptible patient nearby surfaces was significantly linearly associated with the hand-touch frequency (p < 0.05). The noncompliance of daily cleaning on patient nearby high-touch surfaces (HTSs) had the most impact on MRSA transmission. If the HTSs were not cleaned, the MRSA exposure to Type 1 and 2 susceptible patients would increase 118.4% (standard deviation (SD): 33.0%) and 115.4% (SD: 30.5%) respectively. The communal surfaces (CSs) had the least impact, if CSs were not cleaned, the MRSA exposure to Type 1 susceptible patient would only increase 1.7% (SD: 1.3). The impact of clinical equipment (CE) differed largely for two types of susceptible patients. If the CE was not cleaned, the exposure to Type 1 patients would only increase 8.4% (SD: 3.0%), while for Type 2 patients, it can increase 70.4% (SD: 25.4%).

Conclusions

This study provided a framework to study the pathogen concentration dynamics on environmental surfaces and quantitatively showed the importance of cleaning patient nearby HTSs on controlling the nosocomial infection transmission via contact route.

Environmental contamination by carbapenem-resistant Acinetobacter baumannii: The effects of room type and cleaning methods

OBJECTIVE

We evaluated environmental contamination by carbapenem-resistant Acinetobacter baumannii (CRAB), the effectiveness of cleaning practices, the performance of aerosolized hydrogen-peroxide (aHP) technology, and the correlation between measures of cleaning and environmental contamination.

DESIGN

Serial testing of environmental contamination during a 7-month period.

SETTING

Single-patient rooms in intensive care units (ICUs) and multipatient step-up and regular rooms in internal medicine wards in a tertiary-care hospital with endemic CRAB.

METHODS

CRAB environmental contamination was determined semiquantitatively using sponge sampling.

RESULTS

In step-up rooms, 91% of patient units (56% of objects) were contaminated, and half of them were heavily contaminated. In regular rooms, only 21% of patient units (3% of objects) were contaminated. In ICUs, 76% of single-patient rooms (24% of objects) were contaminated. Cleaning did not reduce the number of contaminated objects or patient units in step-up rooms. After refresher training, cleaning reduced the proportion of contaminated objects by 2-fold (P = .001), but almost all patient units remained contaminated. Using aerosolized hydrogen peroxide (aHP) disinfection after discharge of a known CRAB-carrier decreased room contamination by 78%, similar to the reduction achieved by manual hypochloride cleaning. Measuring cleaning efficacy using fluorescent gel did not correlate with recovery of CRAB by sponge cultures.

CONCLUSIONS

In step-up rooms, the high number of objects contaminated combined with poor efficacy of cleaning resulted in failure to eliminate CRAB in patient units. Fluorescent gel is a poor detector of CRAB contamination. The role of aHP is still unclear. However, its use in multipatient rooms is limited because it can only be used in unoccupied rooms.

Clostridium Difficile: Reducing Infections Using an Evidence-Based Practice Initiative

BACKGROUND

Nosocomial Clostridium difficile (C. difficile) infections are adverse incidents that affect immunocompromised hospitalized patients. High-touch surface areas within the patient's environment are frequently overlooked and are a source of microscopic bacterial transmission.

OBJECTIVES

This article examines whether the use of a standardized protocol for cleaning high-touch surface areas would reduce the incidence of hospital-acquired C. difficile infection.

METHODS

The initiative targeted five high-touch surfaces, and nurses were educated about these findings. Baseline data on the C. difficile infection rate was collected from four specialty medical-surgical oncology units. A pilot period of the Five by Five initiative evaluated C. difficile infection rates after staff cleaning of these high-touch surfaces.

FINDINGS

This initiative accounted for a statistically significant reduction in C. difficile infections. The use of a standardized cleaning initiative was effective in reducing C. difficile infections. Nursing staff perceived that the education was easy to remember and supported efficient implementation.

Evaluation of an Ultraviolet C (UVC) Light-Emitting Device for Disinfection of High Touch Surfaces in Hospital Critical Areas

Implementation of environmental cleaning and disinfection has been shown to reduce the incidences of healthcare-associated infections. The effect of an enhanced strategy for terminal room disinfection, applying the pulsed xenon-based ultraviolet light no-touch disinfection systems (PX-UVC) after the current standard operating protocol (SOP) was evaluated. In a teaching hospital, the effectiveness in reducing the total bacterial count (TBC) and in eliminating high-concern microorganisms was assessed on five high-touch surfaces in different critical areas, immediately pre- and post-cleaning and disinfection procedures (345 sampling sites). PX-UVC showed only 18% (15/85) of positive samples after treatment compared to 63% (72/115) after SOP. The effectiveness of PX-UVC was also observed in the absence of manual cleaning and application of a chemical disinfectant. According to the hygienic standards proposed by the Italian Workers Compensation Authority, 9 of 80 (11%) surfaces in operating rooms showed TBC ≥15 CFU/24 cm² after the SOP, while all samples were compliant applying the SOP plus PX-UVC disinfection. Clostridium difficile (CD) spores and Klebsiella pneumoniae (KPC) were isolated only after the SOP. The implementation of the standard cleaning and disinfection procedure with the integration of the PX-UVC treatment had effective results in both the reduction of hygiene failures and in control environmental contamination by high-concern microorganisms.

How to carry out microbiological sampling of healthcare environment surfaces? A review of current evidence

There is increasing evidence that the hospital surface environment contributes to the spread of pathogens. However, evidence on how best to sample these surfaces is inconsistent and there is no guidance or legislation in place on how to do this. The aim of this review was to assess current literature on surface sampling methodologies, including the devices used, processing methods, and the environmental and biological factors that might influence results. Studies published prior to March 2019 were selected using relevant keywords from ScienceDirect, Web of Science, and PubMed. Abstracts were reviewed and all data-based studies in peer-reviewed journals in the English language were included. Microbiological air and water sampling in the hospital environment were not included. Although the numbers of cells or virions recovered from hospital surface environments were generally low, the majority of surfaces sampled were microbiologically contaminated. Of the organisms detected, multidrug-resistant organisms and clinically significant pathogens were frequently isolated and could, therefore, present a risk to vulnerable patients. Great variation was found between methods and the available data were incomplete and incomparable. Available literature on sampling methods demonstrated deficits with potential improvements for future research. Many of the studies included in the review were laboratory-based and not undertaken in the real hospital environment where sampling recoveries could be affected by the many variables present in a clinical environment. It was therefore difficult to draw overall conclusions; however, some recommendations for the design of routine protocols for surface sampling of healthcare environments can be made.

Are Visitors Dangerous Carriers of Pathogens in The Hospital? an Observational Study in an University Hospital in Sicily

The hospital environment has been suggested as having an important role in the transmission of health care-associated infections. The aim of this work is to clarify the possible role of visitors in environmental contamination at our hospital. The microbial load was determined by Rodac plate contact on flat surfaces and by swabs on uneven surfaces. A total of 137 samples were taken from four different areas of the hospital unit. The results were divided into two groups according to the types of subjects that most often frequented those environments. We found that the transmission of health care-associated infections (HAIs) occurs mainly in areas where visitors are not allowed.

'Off the rails': hospital bed rail design, contamination, and the evaluation of their microbial ecology

Microbial contamination of the near-patient environment is an acknowledged reservoir for nosocomial pathogens. The hospital bed and specifically bed rails have been shown to be frequently and heavily contaminated in observational and interventional studies. Whereas the complexity of bed rail design has evolved over the years, the microbial contamination of these surfaces has been incompletely evaluated. In many published studies, key design variables are not described, compromising the extrapolation of results to other settings. This report reviews the evolving structure of hospital beds and bed rails, the possible impact of different design elements on microbial contamination and their role in pathogen transmission. Our findings support the need for clearly defined standardized assessment protocols to accurately assess bed rail and similar patient zone surface levels of contamination, as part of environmental hygiene investigations.

Tracking Staphylococcus aureus in the intensive care unit using whole-genome sequencing

BACKGROUND

Staphylococcus aureus remains an important bacterial pathogen worldwide. This study utilized known staphylococcal epidemiology to track S. aureus between different ecological reservoirs in one 10-bed intensive care unit (ICU).

METHODS

Selected hand-touch surfaces, staff hands and air were screened systematically 10 times during 10 months, with patients screened throughout the study. S. aureus isolates were subjected to spa typing and epidemiological analyses, followed by whole-genome sequencing to provide single nucleotide polymorphism (SNP) data.

RESULTS

Multiple transmission pathways between patients and reservoirs were investigated. There were 34 transmission events, of which 29 were highly related (<25 SNPs) and five were possibly related (<50 SNPs). Twenty (59%) transmission events occurred between colonized patients and their own body sites (i.e. autogenous spread); four (12%) were associated with cross-transmission between patients; four (12%) occurred between patients and hand-touch sites (bedrails and intravenous pump); four (12%) linked airborne S. aureus with staff hands and bedrail; and two (6%) linked bed tables, bedrail and cardiac monitor.

CONCLUSION

Colonized patients are responsible for repeated introduction of new S. aureus into the ICU, whereupon a proportion spread to hand-touch sites in (or near) the patient zone. This short-term reservoir for S. aureus imposes a colonization/infection risk for subsequent patients. More than half of ICU-acquired S. aureus infection originated from the patients' own flora, while staff hands and air were rarely implicated in onward transmission. Control of staphylococcal infection in the ICU is best served by patient screening, systematic cleaning of hand-touch surfaces and continued emphasis on hand hygiene.

Four steps to clean hospitals: LOOK, PLAN, CLEAN and DRY

BACKGROUND

Now that cleaning and decontamination are recognized as integral to infection control, it is timely to examine the process in more detail. This is because cleaning practices vary widely within healthcare districts, and it is likely that both time and energy are needlessly wasted with ill-defined duties. Furthermore, inadequate cleaning will not reduce the risk of infection but may even enhance it. The process would benefit from a systematic appraisal, with each component placed within an evidence-based and ordered protocol.

METHODS

A literary search was performed on 'hospital cleaning', focusing on manual aspects of cleaning, pathogen reservoirs and transmission, hand hygiene, staff responsibilities and patient comfort.

RESULTS

No articles providing an evidence-based practical approach to systematic cleaning in hospitals were identified. This review therefore proposes a simple four-step guide for daily cleaning of the occupied bed space. Step 1 (LOOK) describes a visual assessment of the area to be cleaned; Step 2 (PLAN) argues why the bed space needs preparation before cleaning; Step 3 (CLEAN) covers surface cleaning/decontamination; and Step 4 (DRY) is the final stage whereby surfaces are allowed to dry.

CONCLUSION

Given the lack of articles providing practical cleaning guidance, this review proposes a four-step protocol based on evidence if available, or justified where not. Each step is presented, discussed and risk-assessed. It is likely that a systematic cleaning process would reduce the risk of healthcare-associated infection for everyone, including outbreaks, in addition to heightened confidence in overall quality of care.

A microbiological study to investigate the carriage and transmission-potential of Clostridium difficile spores on single-use and reusable sharps containers

BACKGROUND

A 2015 study matching use of disposable and reusable sharps containers (DSCs, RSCs) with Clostridium difficile infection (CDI) incidence found a decreased incidence with DSCs. We conducted microbiologic samplings and examined the literature and disease-transmission principles to evaluate the scientific feasibility of such an association.

METHODS

(i) 197 RSCs were sampled for C. difficile at processing facilities; (ii) RSCs were challenged with high C. difficile densities to evaluate efficacy of automated decontamination; and (iii) 50 RSCs and 50 DSCs were sampled in CDI patient rooms in 7 hospitals. Results were coupled with epidemiologic studies, clinical requirements, and chain-of-infection principles, and tests of evidence of disease transmission were applied.

RESULTS

C. difficile spores were found on 9 of 197 (4.6%) RSCs prior to processing. Processing completely removed C. difficile. In CDI patient rooms, 4 of 50 RSCs (8.0%) and 8 of 50 DSCs (16.0%) had sub-infective counts of C. difficile (P = .27). DSCs were in permanent wall cabinets; RSCs were removed and decontaminated frequently.

CONCLUSION

With C. difficile bioburden being sub-infective on both DSCs and RSCs, sharps containers being no-touch, and glove removal required after sharps disposal, we found 2 links in the chain of infection to be broken and 5 of 7 tests of evidence to be unmet. We conclude that sharps containers pose no risk of C. difficile transmission.

Nosocomial outbreaks caused by Acinetobacter baumannii and Pseudomonas aeruginosa: Results of a systematic review

BACKGROUND

Large outbreaks of infection by Acinetobacter baumannii and Pseudomonas aeruginosa have been reported. This research compares characteristics of such outbreaks.

OBJECTIVES

Determination of risk factors for the occurrence and appropriate infection control measures.

DATA SOURCES

The Outbreak Database, PubMed, and reference lists of identified articles were used. Key words included nosocomial and (outbreak or epidemic) and (aeruginosa or baumannii).

STUDY ELIGIBILITY CRITERIA

Articles were included if they describe distinct outbreak(s) caused by A baumannii or P aeruginosa and were published between 2000 and 2015. There were no further restrictions with respect to language or type of article.

RESULTS

One hundred fifty outbreaks by A baumannii and 131 outbreaks by P aeruginosa were included, including multidrug-resistant strains in 113 Acinetobacter and 49 Pseudomonas outbreaks. Acinetobacter outbreaks were mainly reported from intensive care units, after use of antibiotics, during mechanical ventilation, and presented with a mortality rate of 47% compared with 23% by Pseudomonas. Resistance did not alter mortality by either species. Most infection control measures were implemented or enforced more often in Acinetobacter outbreaks.

CONCLUSIONS

These findings should support staff in infection control departments and on wards if an outbreak is suspected. Better adherence to the Outbreak Reports and Intervention Studies of Nosocomial Infection guidelines in outbreak reporting is necessary. A precise definition of multidrug resistance for Acinetobacter and Pseudomonas is lacking.

Spatial and environmental correlates of organism colonization and infection in the neonatal intensive care unit

OBJECTIVE

To examine organism colonization and infection in the neonatal intensive care unit as a result of environmental and spatial factors.

STUDY DESIGN

A retrospective cohort of infants admitted between 2006 and 2015 (n = 11 428), to assess the relationship between location and four outcomes: methicillin-resistant Staphylococcus aureus (MRSA) colonization; culture-confirmed late-onset sepsis; and, if intubated, endotracheal tube colonization with Pseudomonas aeruginosa or Klebsiella pneumonia. Independent risk factors were identified with mixed-effects logistic regression models and Moran's I for spatial autocorrelation.

RESULT

All four outcomes statistically clustered by location; neighboring colonization also influenced risk of MRSA (p < 0.05). For P. aeruginosa, being in a location with space for more medical equipment was associated with 2.61 times the odds of colonization (95% CrI: 1.19, 5.78).

CONCLUSION

Extrinsic factors partially explained risk for neonatal colonization and infection. For P. aeruginosa, infection prevention efforts at locations with space for more equipment may lower future colonization.

Is there an association between airborne and surface microbes in the critical care environment?

BACKGROUND

There are few data and no accepted standards for air quality in the intensive care unit (ICU). Any relationship between airborne pathogens and hospital-acquired infection (HAI) risk in the ICU remains unknown.

AIM

First, to correlate environmental contamination of air and surfaces in the ICU; second, to examine any association between environmental contamination and ICU-acquired staphylococcal infection.

METHODS

Patients, air, and surfaces were screened on 10 sampling days in a mechanically ventilated 10-bed ICU for a 10-month period. Near-patient hand-touch sites (N = 500) and air (N = 80) were screened for total colony count and Staphylococcus aureus. Air counts were compared with surface counts according to proposed standards for air and surface bioburden. Patients were monitored for ICU-acquired staphylococcal infection throughout.

FINDINGS

Overall, 235 of 500 (47%) surfaces failed the standard for aerobic counts (≤2.5 cfu/cm²). Half of passive air samples (20/40: 50%) failed the 'index of microbial air' contamination (2 cfu/9 cm plate/h), and 15/40 (37.5%) active air samples failed the clean air standard (<10 cfu/m³). Settle plate data were closer to the pass/fail proportion from surfaces and provided the best agreement between air parameters and surfaces when evaluating surface benchmark values of 0-20 cfu/cm². The surface standard most likely to reflect hygiene pass/fail results compared with air was 5 cfu/cm². Rates of ICU-acquired staphylococcal infection were associated with surface counts per bed during 72h encompassing sampling days (P = 0.012).

CONCLUSION

Passive air sampling provides quantitative data analogous to that obtained from surfaces. Settle plates could serve as a proxy for routine environmental screening to determine the infection risk in ICU.

Specialized cleaning associated with antimicrobial coatings for reduction of hospital-acquired infection: opinion of the COST Action Network AMiCI (CA15114)

Recognized issues with poor hand hygiene compliance among healthcare workers and reports of recontamination of previously chemically disinfected surfaces through hand contact emphasize the need for novel hygiene methods in addition to those currently available. One such approach involves antimicrobial (nano) coatings (AMCs), whereby integrated active ingredients are responsible for elimination of micro-organisms that come into contact with treated surfaces. While widely studied under laboratory conditions with promising results, studies under real-life healthcare conditions are scarce. The views of 75 contributors from 30 European countries were collated regarding specialized cleaning associated with AMCs for reduction of healthcare-associated infection. There was unanimous agreement that generation of scientific guidelines for cleaning of AMCs, using traditional or new processes, is needed. Specific topics included: understanding mechanisms of action of cleaning materials and their physical interactions with conventional coatings and AMCs; that assessments mimic the life cycle of coatings to determine the impact of repetitive cleaning and other aspects of ageing (e.g. exposure to sunlight); determining concentrations of AMC-derived biocides in effluents; and development of effective de-activation and sterilization treatments for cleaning effluents. Further, the consensus opinion was that, prior to widespread implementation of AMCs, there is a need for clarification of the varying responsibilities of involved clinical, healthcare management, cleaning services and environmental safety stakeholders.

Role of Hand Hygiene Ambassador and Implementation of Directly Observed Hand Hygiene Among Residents in Residential Care Homes for the Elderly in Hong Kong

OBJECTIVEMultidrug-resistant organisms (MDROs) are increasingly reported in residential care homes for the elderly (RCHEs). We assessed whether implementation of directly observed hand hygiene (DOHH) by hand hygiene ambassadors can reduce environmental contamination with MDROs.METHODSFrom July to August 2017, a cluster-randomized controlled study was conducted at 10 RCHEs (5 intervention versus 5 nonintervention controls), where DOHH was performed at two-hourly intervals during daytime, before meals and medication rounds by a one trained nurse in each intervention RCHE. Environmental contamination by MRDOs, such as methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Acinetobacter species (CRA), and extended-spectrum β-lactamse (ESBL)-producing Enterobacteriaceae, was evaluated using specimens collected from communal areas at baseline, then twice weekly. The volume of alcohol-based hand rub (ABHR) consumed per resident per week was measured.RESULTSThe overall environmental contamination of communal areas was culture-positive for MRSA in 33 of 100 specimens (33%), CRA in 26 of 100 specimens (26%), and ESBL-producing Enterobacteriaceae in 3 of 100 specimens (3%) in intervention and nonintervention RCHEs at baseline. Serial monitoring of environmental specimens revealed a significant reduction in MRSA (79 of 600 [13.2%] vs 197 of 600 [32.8%]; P<.001) and CRA (56 of 600 [9.3%] vs 94 of 600 [15.7%]; P=.001) contamination in the intervention arm compared with the nonintervention arm during the study period. The volume of ABHR consumed per resident per week was 3 times higher in the intervention arm compared with the baseline (59.3±12.9 mL vs 19.7±12.6 mL; P<.001) and was significantly higher than the nonintervention arm (59.3±12.9 mL vs 23.3±17.2 mL; P=.006).CONCLUSIONSThe direct observation of hand hygiene of residents could reduce environmental contamination by MDROs in RCHEs.Infect Control Hosp Epidemiol 2018;39:571-577.

Interaction of healthcare worker hands and portable medical equipment: a sequence analysis to show potential transmission opportunities

Background

While research has demonstrated the importance of a clean health care environment, there is a lack of research on the role portable medical equipment (PME) play in the transmission cycle of healthcare-acquired infections (HAIs). This study investigated the patterns and sequence of contact events among health care workers, patients, surfaces, and medical equipment in a hospital environment.

Methods

Research staff observed patient care events over six different 24 h periods on six different hospital units. Each encounter was recorded as a sequence of events and analyzed using sequence analysis and visually represented by network plots. In addition, a point prevalence microbial sample was taken from the computer on wheels (COW).

Results

The most touched items during patient care was the individual patient (850), bedrail (375), bed-surface (302), and bed side Table (223). Three of the top ten most common subsequences included touching PME and the patient: computer on wheels ➔ patient (62 of 274 total sequences, 22.6%, contained this sequence), patient ➔ COW (20.4%), and patient ➔ IV pump (16.1%). The network plots revealed large interconnectedness among objects in the room, the patient, PME, and the healthcare worker.

Conclusions

Our results demonstrated that PME such as COW and IV pump were two of the most highly-touched items during patient care. Even with proper hand sanitization and personal protective equipment, this sequence analysis reveals the potential for contamination from the patient and environment, to a vector such as portable medical equipment, and ultimately to another patient in the hospital.

Electronic supplementary material

The online version of this article (10.1186/s12879-017-2895-6) contains supplementary material, which is available to authorized users.

What Healthcare Workers Should Know about Environmental Bacterial Contamination in the Intensive Care Unit

Intensive care unit- (ICU-) acquired infections are a major health problem worldwide. Inanimate surfaces and equipment contamination may play a role in cross-transmission of pathogens and subsequent patient colonization or infection. Bacteria contaminate inanimate surfaces and equipment of the patient zone and healthcare area, generating a reservoir of potential pathogens, including multidrug resistant species. Traditional terminal cleaning methods have limitations. Indeed patients who receive a bed from prior patient carrying bacteria are exposed to an increased risk (odds ratio 2.13, 95% confidence intervals 1.62-2.81) of being colonized and potentially infected by the same bacterial species of the previous patient. Biofilm formation, even on dry surfaces, may play a role in reducing the efficacy of terminal cleaning procedures since it enables bacteria to survive in the environment for a long period and provides increased resistance to commonly used disinfectants. No-touch methods (e.g., UV-light, hydrogen peroxide vapour) are under investigation and further studies with patient-centred outcomes are needed, before considering them the standard of terminal cleaning in ICUs. Healthcare workers should be aware of the role of environmental contamination in the ICU and consider it in the broader perspective of infection control measures and stewardship initiatives.

Cross-sectional point prevalence survey to study the environmental contamination of nosocomial pathogens in intensive care units under real-life conditions

BACKGROUND

In intensive care units (ICUs), inanimate surfaces and equipment may be contaminated by nosocomial pathogens, including multi-drug-resistant micro-organisms.

AIMS

To assess the degree of environmental contamination close to and distant from patients, and contamination of healthcare workers' (HCWs) hands with nosocomial pathogens under real-life conditions and to investigate potential transmission events.

METHODS

Over the course of three weeks, agar contact samples were taken close to and distant from patient areas and from HCWs' hands in eight ICUs of a tertiary care hospital in Innsbruck, Austria. Each ICU was visited once without announcement. Species identification and antimicrobial susceptibility testing were performed according to standard methods, and corresponding strains from patient, environment and hand samples were genotyped using pulsed-field gel electrophoresis.

FINDINGS

Among 523 samples, HCWs' hands were most frequently contaminated with potentially pathogenic bacteria (15.2%), followed by areas close to patients (10.9%) and areas distant from patients (9.1%). Gram-positive bacteria were identified most often (67.8%), with Enterococcus spp. being the most prevalent species (70% vancomycin sensitive and 30% vancomycin resistant) followed by Staphylococcus aureus, of which 64% were classified as meticillin-resistant Staphylococcus aureus. Molecular typing documented identical strains among patient, environment and hand isolates.

CONCLUSION

This study found widespread contamination of the ICU environment with clinically relevant pathogens, including multi-drug-resistant micro-organisms, despite cleaning and disinfection. The bioburden might not be restricted to areas close to patients. The role of extended environmental disinfection of areas distant from patients in order to improve infection prevention needs further discussion.