33 research outputs found
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
How to carry out microbiological sampling of healthcare environment surfaces? A review of current evidence
BACKGROUND: 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 patchy and there is no guidance or legislation in place on how to do this. AIM: The aim of this review was to assess current literature on surface sampling methodologies, including the devices used, processing methods, the environmental and biological factors that might influence results. METHODS: 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. FINDINGS: 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, multi-drug 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 was incomplete and incomparable. CONCLUSION: 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
Does size matter? The impact of a small but targeted cleaning training intervention within a paediatric ward
Background: Cleaning is a critical tool for infection prevention and control, and is a key intervention for preventing healthcare associated infections (HCAIs) and controlling intermediate transmission routes between patient and environment. This study sought to identify potential areas of weakness in clinical surface cleaning, and assess the effectiveness of a staff group specific training intervention. Observations: One-hundred hours of audit observations in a paediatric cardiac intensive care unit (CICU) assessed surface cleaning technique of healthcare staff within bedspaces. Cleaning was assessed with a 5-component bundle, with each cleaning opportunity scored out of five. Training Intervention: Fifty hours of audit observations before and after a training intervention tested the efficacy of a staff group specific education intervention. The intervention was developed and implemented for 69% of nurses and 100% of cleaners. Results: One hundred and eighteen cleaning opportunities were observed before training, and scored an average of 2.4. One hundred and twenty-one cleaning opportunities were observed after training and scored an average 3.0. On average, before training, each cleaning opportunity by nurses and cleaners fulfilled 2.4 and 2.5, respectively, of the 5 bundle components. Following training, this improved to 3.3 and 2.9 respectively. There was a statistically significant improvement in bundle scores for nurses (P=.004) and cleaners (P=.0003). Conclusions: Surface wipe methods were inconsistent between all staff groups. The education based intervention resulted in a small improvement in most of the cleaning components. This study has identified how a small but targeted cleaning training intervention can have a significant (P= <.0001) impact on cleaning bundle compliance for both nurses and cleaners
Controlling Legionella pneumophila in water systems at reduced hot water temperatures with copper and silver ionization
Background: Hospital-acquired Legionnaires’ disease is associated with the presence of Legionella pneumophila in hospital water systems. In the United Kingdom, the Department of Health recommends maintaining hot water temperatures >55°C and cold water temperatures <20°C at the point of delivery to prevent proliferation of L pneumophila in water systems. In this study, we evaluated the efficacy of copper and silver ionization to control L pneumophila at deliberately reduced hot water temperatures (43°C) within a newly installed water system in a new building linked to a large health care facility in the United Kingdom. / Methods: One thousand, five hundred ninety-eight water samples were collected between September 2011 and June 2017. Samples were tested using accredited methods for L pneumophila, copper and silver ion levels, and total viable counts. Energy consumption and water usage data were also collected to permit carbon emission calculations. / Results: The results of 1,598 routine samples from September 2011 to June 2017, and the recordings of temperatures at outlets in this facility, demonstrated effective (100%) L pneumophila control throughout the study period with an average hot water temperature of 42°C. The energy savings and reduction of carbon emissions were calculated to amount to 33% and 24%, respectively, compared to an equivalent temperature-controlled system. Water system management interventions were required to achieve consistently adequate levels of copper and silver across outlets. / Conclusions: This study demonstrated that it is possible to control L pneumophila independent of temperature when copper and silver ionization is introduced into a new building in conjunction with an appropriately managed water system
Gyrospun antimicrobial nanoparticle loaded fibrous polymeric filters
A one step approach to prepare hybrid nanoparticle embedded polymer fibres using pressurised gyration is presented. Two types of novel antimicrobial nanoparticles and poly(methylmethacrylate) polymer were used in this work. X-ray diffraction analysis of the nanoparticles revealed Ag, Cu and W are the main elements present in them. The concentration of the polymer solution and the nanoparticle concentration had a significant influence on the fibre diameter, pore size and morphology. Fibres with a diameter in the range of 6-20. ÎĽm were spun using 20. wt% polymer solutions containing 0.1, 0.25 and 0.5 wt% nanoparticles under 0.3. MPa working pressure and a rotational speed of 36,000. rpm. Continuous, bead-free fibre morphologies were obtained for each case. The pore size in the fibres varied between 36 and 300. nm. Successful incorporation of the nanoparticles in polymer fibres was confirmed by energy dispersive x-ray analysis. The fibres were also gyrospun on to metallic discs to prepare filters which were tested for their antibacterial activity on a suspension of Pseudomonas aeruginosa. Nanoparticle loaded fibres showed higher antibacterial efficacy than pure poly(methylmethacrylate) fibres
Hospital Door Handle Design and Their Contamination with Bacteria: A Real Life Observational Study. Are We Pulling against Closed Doors?
Objective
To determine whether microbial contamination of door handles in two busy intensive care units and one high dependency unit was related to their design, location, and usage.
Design
Observational study of the number of viable bacteria on existing door handles of different design at defined entry/exit points with simultaneous data collection of who used these doors and how often.
Setting
Two busy specialised intensive care units and one high dependency unit in a tertiary referral NHS neurological hospital.
Main outcome measures
Surface bacterial density on door handles with reference to design, location, and intensity of use.
Results
We found a significant correlation between the frequency of movements through a door and the degree to which it was contaminated (p = <0.01). We further found that the door's location, design and mode of use all influenced contamination. When compared to push plate designs, pull handles revealed on average a five fold higher level of contamination; lever handles, however, displayed the highest levels of bacterial contamination when adjusted for frequency of use. We also observed differences in contamination levels at doors between clinical areas, particularly between the operating theatres and one of the ICUs.
Conclusions
Door handles in busy, “real life” high acuity clinical environments were variably contaminated with bacteria, and the number of bacteria found related to design, location, mode and frequency of operation. Largely ignored issues of handle and environmental design can support or undermine strategies designed to limit avoidable pathogen transmission, especially in locations designed to define “thresholds” and impose physical barriers to pathogen transmission between clinical areas. Developing a multidisciplinary approach beyond traditional boundaries for purposes of infection control may release hitherto unappreciated options and beneficial outcomes for the control of at least some hospital acquired infections
Use of Whole-genome Sequencing of Adenovirus in Immunocompromised Paediatric Patients to Identify Nosocomial Transmission and Mixed-genotype Infection
Background: Adenoviruses are significant pathogens for the immunocompromised, arising from primary infection or reinfection. Serotyping is insufficient to support nosocomial transmission investigations. We investigate whether whole-genome sequencing (WGS) provides clinically relevant information on transmission among patients in a paediatric tertiary hospital. Methods: We developed a target-enriched adenovirus WGS technique for clinical samples and retrospectively sequenced 107 adenovirus-positive residual diagnostic samples, including viraemias (>5x104 copies/ml), from 37 patients collected January 2011 - March 2016. WGS was used to determine genotype and for phylogenetic analysis. Results: Adenovirus sequences were recovered from 105/107 samples. Full genome sequences were recovered from all 20 non-species C samples and from 36/85 species C viruses, with partial genome sequences recovered from the rest. Whole genome phylogenetic analysis suggested linkage of three genotype A31 cases and uncovered an unsuspected epidemiological link to an A31 infection first detected on the same ward four years earlier. In nine samples from one patient who died we identified a mixed genotype adenovirus infection. Conclusions: Adenovirus WGS from clinical samples is possible and useful for genotyping and molecular epidemiology. WGS identified likely nosocomial transmission with greater resolution than conventional genotyping, and distinguished between adenovirus disease due to single or multiple genotypes
Statistical analysis plan for the LAKANA trial: a cluster-randomized, placebo-controlled, double-blinded, parallel group, three-arm clinical trial testing the effects of mass drug administration of azithromycin on mortality and other outcomes among 1–11-month-old infants in Mali
BACKGROUND:The Large-scale Assessment of the Key health-promoting Activities of two New mass drug administration regimens with Azithromycin (LAKANA) trial in Mali aims to evaluate the efficacy and safety of azithromycin (AZI) mass drug administration (MDA) to 1–11-month-old infants as well as the impact of the intervention on antimicrobial resistance (AMR) and mechanisms of action of azithromycin. To improve the transparency and quality of this clinical trial, we prepared this statistical analysis plan (SAP). METHODS/DESIGN: LAKANA is a cluster randomized trial that aims to address the mortality and health impacts of biannual and quarterly AZI MDA. AZI is given to 1–11-month-old infants in a high-mortality setting where a seasonal malaria chemoprevention (SMC) program is in place. The participating villages are randomly assigned to placebo (control), two-dose AZI (biannual azithromycin-MDA), and four-dose AZI (quarterly azithromycin-MDA) in a 3:4:2 ratio. The primary outcome of the study is mortality among the intention-to-treat population of 1–11-month-old infants. We will evaluate relative risk reduction between the study arms using a mixed-effects Poisson model with random intercepts for villages, using log link function with person-years as an offset variable. We will model outcomes related to secondary objectives of the study using generalized linear models with considerations on clustering. CONCLUSION: The SAP written prior to data collection completion will help avoid reporting bias and data-driven analysis for the primary and secondary aims of the trial. If there are deviations from the analysis methods described here, they will be described and justified in the publications of the trial results. TRIAL REGISTRATION: ClinicalTrials.gov ID NCT04424511. Registered on 11 June 2020
Gyrospun antimicrobial nanoparticle loaded fibrous polymeric filters
© 2016 The Authors. Published by Elsevier B.V. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).A one step approach to prepare hybrid nanoparticle embedded polymer fibres using pressurised gyration is presented. Two types of novel antimicrobial nanoparticles and poly (methylmethacrylate) polymer were used in this work. X-ray diffraction analysis of the nanoparticles revealed Ag, Cu and W are the main elements present in them. The concentration of the polymer solution and the nanoparticle concentration had a significant influence on the fibre diameter, pore size and morphology. Fibres with a diameter in the range of 6-20 ìm were spun using 20 wt% polymer solutions containing 0.1, 0.25 and 0.5 w% nanoparticles under 0.3 MPa working pressure and a rotational speed of 36000 rpm. Continuous, bead-free fibre morphologies were obtained for each case. The pore size in the fibres varied between 36-300 nm. Successful incorporation of the nanoparticles in polymer fibres was confirmed by energy dispersive x-ray analysis. The fibres were also gyrospun on to metallic disks to prepare filters which were tested for their antibacterial activity on a suspension of Pseudomonas aeruginosa. Nanoparticle loaded fibres showed higher antibacterial efficacy than pure poly(methylmethacrylate) fibres.8pÍuPeer reviewedFinal Published versio
International multicenter evaluation of the DiversiLab bacterial typing system for Escherichia coli and Klebsiella spp.
Successful multidrug-resistant clones are increasing in prevalence globally, which makes the ability to identify these clones urgent. However, adequate, easy-to-perform, and reproducible typing methods are lacking. We investigated whether DiversiLab (DL), an automated repetitive-sequence-based PCR bacterial typing system (bioMĂ©rieux), is suitable for comparing isolates analyzed at different geographic centers. A total of 39 Escherichia coli and 39 Klebsiella species isolates previously typed by the coordinating center were analyzed. Pulsed-field gel electrophoresis (PFGE) confirmed the presence of one cluster of 6 isolates, three clusters of 3 isolates, and three clusters of 2 isolates for each set of isolates. DL analysis was performed in 11 centers in six different countries using the same protocol. The DL profiles of 425 E. coli and 422 Klebsiella spp. were obtained. The DL system showed a lower discriminatory power for E. coli than did PFGE. The local DL data showed a low concordance, as indicated by the adjusted Rand and Wallace coefficients (0.132 to 0.740 and 0.070 to 1.0 [E. coli] and 0.091 to 0.864 and 0.056 to 1.0 [Klebsiella spp.], respectively). The central analysis showed a significantly improved concordance (0.473 to 1.0 and 0.290 to 1.0 [E. coli] and 0.513 to 0.965 and 0.425 to 1.0 [Klebsiella spp.], respectively). The misclassifications of profiles for individual isolates were mainly due to inconsistent amplification, which was most likely due to variations in the quality and amounts of the isolated DNA used for amplification. Despite local variations, the DL system has the potential to indicate the occurrence of clonal outbreaks in an international setting, provided there is strict adherence to standardized, reproducible DNA isolation methods and analysis protocols, all supported by a central database for profile comparisons