Methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii on computer interface surfaces of hospital wards and association with clinical isolates

Ozonated water in disinfection of hospital instrument table

Purpose

The walls, ceiling, and floor of a surgical environment, as well as the surfaces used in this place, must be submitted to a disinfection protocol to minimize nosocomial infections. Health regulations recommend two stages; the first is characterized by cleaning procedures, mainly using an enzymatic detergent, and the second is use of a disinfection agent. Ozone is a natural substance that has a relevant oxidative property for inactivating microorganisms and has emerged as an interesting agent in the hospital environment. Compared with conventional chemical products for disinfection, ozonated water has advantages such as a lack of storage control, disposal, and handling safety. The objective of this study was to use ozonated water as a disinfectant agent on a hospital metal surface, in comparison with 70% alcohol.

Methods

The degree of disinfection of the metal surface was quantitatively analyzed with use of an instrument by bioluminescence for a disinfection test.

Results

Qualitative terms indicated gram-positive cocci microorganisms and yeasts, suggesting that bacteria and fungi from the environment were identified. After the use of ozonated water as a disinfectant, the quantitative analysis indicated values below 100 RLU, showing evidence of a surface suitable for use in surgical procedures.

Conclusion

The use of ozonated water as a disinfectant agent for a metal surface in a hospital environment showed more effectiveness than 70% alcohol. Thus, ozonated water is a promising agent for disinfecting surfaces in surgical environments.

Molecular Characterization of Staphylococci Recovered from Hospital Personnel and Frequently Touched Surfaces in Tianjin, China

Staphylococci are major hospital-associated pathogens, and the dissemination of methicillin-resistant staphylococci in hospitals poses a great challenge for managing hospital-acquired infections. Little is known about the dissemination of staphylococci recovered from the hospital environment and personnel in China. In this study, antimicrobial susceptibility tests, mecA gene detection, SCCmec typing, and multilocus sequence typing (MLST) were performed to clarify the molecular epidemiology of staphylococci in a large hospital in Tianjin, China. One hundred and ninety-five staphylococci were recovered, and 94% of isolates were resistant to at least one antibiotic. Eighty-five staphylococci were mecA gene-positive, and 40% of them harbored SCCmec IV and V. The genotype of Staphylococcus aureus (S. aureus) was ST25, and the dominant genotype of methicillin-resistant Staphylococcus epidermidis (MRSE) was ST59. Three new sequence types were assigned as ST840, ST841, and ST842. One (2%) frequently touched surface was contaminated by S. aureus, which suggested that environmental contamination occurred in the hospital in China. Nineteen (39%) frequently touched surfaces were contaminated by methicillin-resistant coagulase-negative staphylococci (MRCoNS), and 46% of HP carried MRCoNS. Varied staphylococcal species and antimicrobial-resistance rates were observed between staphylococci that were recovered from hospital personnel and frequently touched surfaces. The transmission of MRSE and S. aureus between hospital personnel and frequently touched surfaces was detected. Hospital items and personnel may act as reservoirs of antimicrobial-resistant staphylococci, and cleaning strategies should be carried out to decrease the dissemination of antimicrobial-resistant staphylococci in hospitals in China.

Isolation of extensively drug resistant Acinetobacter baumannii from environmental surfaces inside intensive care units

BACKGROUND

Acinetobacter baumannii is a nosocomial pathogen that has emerged as a major threat in the health-care settings, particularly intensive care units (ICUs). The aim of this study was to investigate the prevalence of A. baumannii in the environment of intensive care and emergency units in 4 hospitals in Jordan.

METHODS

A total of 311 surface and 26 air samples were collected from 6 different ICUs and 2 emergency units. Examined high-touch surfaces included bed rails, sinks, food tables, trolley handles, ventilator inlets, blankets, sheets, door handles, light switches, bedside tables and drawers, curtains, normal saline stands and neonatal incubators. A. baumannii isolates were identified by CHROMagar and confirmed using 2 different PCR assays. All obtained isolates were characterized for their antibiotic resistance phenotypes, biofilm formation capacities and were typed by multi-locus sequence typing.

RESULTS

Of the 337 samples, 24 A. baumannii isolates were recovered, mostly from surfaces in the internal medicine ICUs. Among the 24 isolates, 10 isolates were classified as extensively-resistant (XDR), harbored the bla_OXA-23 like gene and able to form biofilms with varying capacities. ST2 was the most frequent sequence type, with all ST2 isolates classified as XDRs.

CONCLUSIONS

Our results showed that high-touch surfaces of adult and pediatric ICUs were contaminated with XDR A. baumannii isolates. Therefore, the cleaning practices of the surfaces and equipment surrounding ICU patients should be optimized, and health-care workers should continuously wash their hands and change their gloves constantly to control the spread of this pathogen.

Incidence, outcomes, and predictors of Acinetobacter infection in Saudi Arabian critical care units

BACKGROUND

Acinetobacter is an increasingly-problematic organism, especially in intensive care units (ICUs). In this study, we compared its incidence, outcomes, and predictors spanning eight ICUs in five geographically and climatologically-diverse cities in Saudi Arabia.

METHODS

Geographic, climatologic, hospital-related, and patient-related factors were collected prospectively on 3179 patients admitted to eight Saudi ICUs from June 2018 through June 2019. These data then underwent both bivariable and multivariable analysis, the latter vis hierarchical logistic regression to identify predictors of clinically-manifest Acinetobacter infection.

RESULTS

Overall incidence of Acinetobacter infection was 3.9% (n = 124). Of these 124 infections, 122 (98.4%) were cultured as A. baumannii. Incidence ranged from 1.0 to 7.9% across the eight ICUs. On bivariable analysis, incident Acinetobacter infection was more common in university and military hospitals, in hospitals with more total beds and ICU isolation rooms, and in 2018 versus 2019, incidence steadily declining over the 13 study months. Mechanically-ventilated patients had ten-fold increased odds of infection. Adjusted (multivariable) analysis revealed the risk of clinically-manifest Acinetobacter infection to increase the longer patients were on mechanical ventilation. Increased risk also existed at certain hospitals over others, especially in university-affiliated and military hospitals, larger hospitals with more isolation rooms, and hospitals with fewer ICU beds.

CONCLUSION

In our study of eight ICUs across Saudi Arabia, inter-hospital differences did appear to account for inter-hospital differences in Acinetobacter incidence rates. Patients requiring mechanical ventilation for longer periods of time were particularly at risk.

The impact of a 'milking the COW' campaign in a regional hospital in Singapore

Background

Computerisation of various processes in hospitals and reliance on electronic devices raises the concern of contamination of these devices from the patient environment. We undertook this study to determine if an attached hand hygiene device that unlocks the screen of a computer on wheels (COW) on usage can be effective in decreasing the microbiological burden on computer keyboards.

Methods

An electronic hand sanitizer was integrated onto the COW. A prospective cohort study with a crossover design involving 2 control and 2 intervention wards was used. The study end point was the number of colony forming units found on the keyboards. Bacteria were classified into 4 main groups; pathogenic, skin flora, from the environment or those thought to be commensals in healthy individuals. We then used a mixed effects model for the statistical analysis to determine if there were any differences before and after the intervention.

Results

Thirty-nine keyboards were swabbed at baseline, day 7 and 14, with 234 keyboards cultured, colony forming units (CFUs) counted and organisms isolated. By mixed model analysis, the difference of mean bacteria count between intervention and control for week 1 was 32.74 (− 32.74, CI − 94.29 to 28.75, p = 0.29), for week 2 by 155.86 (− 155.86, CI − 227.45 to − 83.53, p < 0.0001), and after the 2-week period by 157.04 (− 157.04, CI − 231.53 to − 82.67, p < 0.0001). In the sub-analysis, there were significant differences of pathogenic bacteria counts for the Intervention as compared to the Control in contrast with commensal counts.

Conclusion

A hand hygiene device attached to a COW may be effective in decreasing the microbiological burden on computer keyboards.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-00948-1.

Hidden reservoirs of pathogens in dental settings

Nosocomial infections are a major concern to both clinicians and health care seekers. Investigations have suggested that laptops & mobile phones may contribute to cross-contamination and can serve as vehicles for infection transmission. Therefore, it is of interest to document the data on hidden reservoirs such as mobile phones and laptops of pathogens in dental settings at the Hazaribag College of dental sciences and Hospital, Jharkhand. The samples were collected from 25 laptops and 25 mobile phones from dentists working in a dental college in Hazaribag city. The samples were collected aseptically using sterile cotton swabs dipped in sterile saline by rotating the swabs on the keyboard surfaces of laptops and mobile phones, inoculated into Brain Heart Infusion broth, vortexed for 1 minute in Fischer Vortex Genie 2 on highest setting & streaked immediately on 5% sheep blood agar plates and were incubated at 37°C for 24 hours aerobically. The isolates were identified based on the colony morphology, colony characteristics and biochemical reactions. The bacterial species isolated were Staphylococcus aureus, Coagulase negative Staphylococcus, Bacillus species, Enterococci, Micrococci, and Pseudomonas etc. Predominant species isolated was Staphylococcus aureus and least was Micrococci. Higher percentage of organisms was found at the Department of Periodontics, Endodontics and least was found in Department of Public Health Dentistry. The percentage and type of organism isolated from keyboards of laptops and mobile phones were similar. Thus, laptops and mobile phones act as vehicles for transfer of potential pathogens associated with dental hospitals. Disinfecting the hands prior to examination of patients and disinfection of laptops and mobiles with alcohol wipes should be done to prevent nosocomial infections.

Usos y limitaciones de la lámpara ultravioleta germicida portátil para la desinfección de superficies

RESUMENLa morbimortalidad causada por infecciones vinculadas a la atención sanatoria ha llevado a cuestionar si los métodos de desinfección convencionales son inadecuados y se requieren métodos complementarios, como la fumigación de la habitación y la irradiación ultravioleta. Ello ha dado lugar a la preocupación por que estos métodos alternativos puedan poner en riesgo al personal sanitario y a los pacientes.Objetivos. (1) Determinar la eficacia de la lámpara ultravioleta C germicida portátil para la desinfección de superficies, (2) evaluar el cambio de la humedad relativa (HR) y las distintas distancias específicas en las tasas de letalidad bacteriana, y (3) evaluar los posibles problemas a que conlleva la exposición.Métodos. En el presente estudio se investiga si una lámpara germicida portátil puede desinfectar de forma eficaz superficies tratadas con esporulación o germinación bacteriana y se evalúa el efecto de condiciones ambientales cambiantes, como la humedad relativa (HR), la posición y las distancias específicas, en las tasas de letalidad germicida.Resultados. Se constató una mejor tasa de letalidad con una HR de 40-65% y en un rango de temperatura de 21-24°C. Tanto la HR alta como la HR baja interfirieron con la capacidad de la radiación UV-C para inactivar la germinación microbiana. En el caso de la esporulación bacteriana, el aumento del secado de la superficie fue el factor de mayor importancia para aumentar la tasa de letalidad.Conclusiones. En esta investigación se demostró la eficacia de la radiación UV-C bajo condiciones óptimas, irradiación directa y una distancia específica corta (12.7 cm). Sin embargo, cuando es utilizada en condiciones que no son óptimas existen limitaciones. El aumento de la distancia y los ángulos de irradiación indirecta resultaron en tasas de letalidad más bajas. Cabe señalar que durante su uso es importante minimizar la exposición innecesaria de pacientes y personal sanitario.

Methicillin Resistant Staphylococcus aureus and public fomites: a review

Staphylococcus genus is a Gram-positive coccus normally associated with skin and mucous membranes of warm-blooded animals. It is part of the commensal human microflora, or found in animals, or contaminating surfaces in the community and hospital settings. Staphylococcus aureus is the most pathogenic species belonging to this genus, as it possesses a collection of virulence factors that are expressed solely to evade the immune system. The increase in the misuse of antimicrobial agents predisposed S. aureus to develop antibiotic resistance, including the resistance to methicillin which led to the emergence of Methicillin-Resistant S. aureus (MRSA). MRSA is considered one of the most dangerous nosocomial pathogens causing many hard to treat infections in hospitals and was named as Hospital Associated MRSA (HA-MRSA). Over the past 20-25 years, MRSA was isolated from community settings and thus Community Associated MRSA (CA-MRSA) has emerged. Inside hospitals, MRSA has been isolated from fomites in contact with patients, as well as staff's protective and personal items. This review highlights the worldwide prevalence of MRSA on fomites within the contexts of hospital and community settings.

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.

Responses of Acinetobacter baumannii Bound and Loose Extracellular Polymeric Substances to Hyperosmotic Agents Combined with or without Tobramycin: An Atomic Force Microscopy Study

In this work, contributions of extracellular polymeric substances (EPS) to the nanoscale mechanisms through which the multidrug-resistant Acinetobacter baumannii responds to antimicrobial and hyperosmotic treatments were investigated by atomic force microscopy. Specifically, the adhesion strengths to a control surface of silicon nitride (Si₃N₄) and the lengths of bacterial surface biopolymers of bound and loose EPS extracted from A. baumannii biofilms were quantified after individual or synergistic treatments with hyperosmotic agents (NaCl and maltodextrin) and an antibiotic (tobramycin). In the absence of any treatment, the loose EPS were significantly longer in length and higher in adhesion to Si₃N₄ than the bound EPS. When used individually, the hyperosmotic agents and tobramycin collapsed the A. baumannii bound and loose EPS. The combined treatment of maltodextrin with tobramycin collapsed only the loose EPS and did not alter the adhesion of both bound and loose EPS to Si₃N₄. In addition, the combined treatment was not as effective in collapsing the EPS molecules as when tobramycin was applied alone. Finally, the effects of treatments were dose-dependent. Altogether, our findings suggest that a sequential treatment could be effective in treating A. baumannii biofilms, in which a hyperosmotic agent is used first to collapse the EPS and limit the diffusion of nutrients into the biofilm, followed by the use of an antibiotic to kill the bacterial cells that escape from the biofilm because of starvation.

Use of Commercial Off-The-Shelf Devices for the Detection of Manual Gestures in Surgery: Systematic Literature Review

Background

The increasingly pervasive presence of technology in the operating room raises the need to study the interaction between the surgeon and computer system. A new generation of tools known as commercial off-the-shelf (COTS) devices enabling touchless gesture–based human-computer interaction is currently being explored as a solution in surgical environments.

Objective

The aim of this systematic literature review was to provide an account of the state of the art of COTS devices in the detection of manual gestures in surgery and to identify their use as a simulation tool for motor skills teaching in minimally invasive surgery (MIS).

Methods

For this systematic literature review, a search was conducted in PubMed, Excerpta Medica dataBASE, ScienceDirect, Espacenet, OpenGrey, and the Institute of Electrical and Electronics Engineers databases. Articles published between January 2000 and December 2017 on the use of COTS devices for gesture detection in surgical environments and in simulation for surgical skills learning in MIS were evaluated and selected.

Results

A total of 3180 studies were identified, 86 of which met the search selection criteria. Microsoft Kinect (Microsoft Corp) and the Leap Motion Controller (Leap Motion Inc) were the most widely used COTS devices. The most common intervention was image manipulation in surgical and interventional radiology environments, followed by interaction with virtual reality environments for educational or interventional purposes. The possibility of using this technology to develop portable low-cost simulators for skills learning in MIS was also examined. As most of the articles identified in this systematic review were proof-of-concept or prototype user testing and feasibility testing studies, we concluded that the field was still in the exploratory phase in areas requiring touchless manipulation within environments and settings that must adhere to asepsis and antisepsis protocols, such as angiography suites and operating rooms.

Conclusions

COTS devices applied to hand and instrument gesture–based interfaces in the field of simulation for skills learning and training in MIS could open up a promising field to achieve ubiquitous training and presurgical warm up.

What's on your keyboard? A systematic review of the contamination of peripheral computer devices in healthcare settings

OBJECTIVE

To determine the extent and type of microbial contamination of computer peripheral devices used in healthcare settings, evaluate the effectiveness of interventions to reduce contamination of these devices and establish the risk of patient and healthcare worker infection from contaminated devices.

DESIGN

Systematic review METHODS: We searched four online databases: MEDLINE, CINAHL, Embase and Scopus for articles reporting primary data collection on contamination of computer-related equipment (including keyboards, mice, laptops and tablets) and/or studies demonstrating the effectiveness of a disinfection technique. Pooling of contamination rates was conducted where possible, and narrative synthesis was used to describe the rates of device contamination, types of bacterial and viral contamination, effectiveness of interventions and any associations between device contamination and human infections.

RESULTS

Of the 4432 records identified, a total of 75 studies involving 2804 computer devices were included. Of these, 50 studies reported contamination of computer-related hardware, and 25 also measured the effects of a decontamination intervention. The overall proportion of contamination ranged from 24% to 100%. The most common microbial contaminants were skin commensals, but also included potential pathogens including methicillin-resistantStaphylococcus aureus, Clostridiumdifficile, vancomycin-resistantenterococci and Escherichia coli. Interventions demonstrating effective decontamination included wipes/pads using isopropyl alcohol, quaternary ammonium, chlorhexidine or dipotassium peroxodisulfate, ultraviolet light emitting devices, enhanced cleaning protocols and chlorine/bleach products. However, results were inconsistent, and there was insufficient data to demonstrate comparative effectiveness. We found little evidence on the link between device contamination and patient/healthcare worker colonisation or infection.

CONCLUSIONS

Computer keyboards and peripheral devices are frequently contaminated; however, our findings do not allow us to draw firm conclusions about their relative impact on the transmission of pathogens or nosocomial infection. Additional studies measuring the incidence of healthcare-acquired infections from computer hardware, the relative risk they pose to healthcare and evidence for effective and practical cleaning methods are needed.

Robust biofilm assay for quantification and high throughput screening applications

Bacterial biofilms are populations of bacteria within a self-produced adherent extracellular matrix that are notoriously resistant to treatment. Existing methods for biofilm quantification are often limited in their dynamic range of detection (signal-to-background), throughput, and require modifications to the protocol depending on the bacterial species. To address these limitations, a broad utility, high-throughput (HTP) method was required. Using a fluorescent dye, FM1-43, we stained the biofilm, followed by solvent extraction and quantitation of biofilm employing a fluorescent plate reader. Utilizing eight different bacterial pathogens, we demonstrate that this method is widely applicable for biofilm quantification. Depending on the species, this biofilm assay offered a large dynamic range of 8-146 fold change compared to 2-22 fold for crystal violet staining under similar conditions. In addition to routine biofilm quantification using this new assay, as a proof-of-concept, 1200 compounds were screened against two different bacterial species to identify biofilm inhibitors. In our HTP screens we successfully identified compounds rifabutin and ethavarine as potential biofilm inhibitors of Burkholderia pseudomallei Bp82 and Acinetobacter baumannii biofilm production respectively. This newly validated biofilm assay is robust and can be readily adapted for antibiofilm screening campaigns and can supplant other less sensitive and low throughput methods.

Bacterial Profile and Antimicrobial Susceptibility Pattern of the Isolates from Stethoscope, Thermometer, and Inanimate Surfaces of Mizan-Tepi University Teaching Hospital, Southwest Ethiopia

Background

Nosocomial infections occur among patients during their stay in hospitals. The severity of infection depends on the characteristics of microorganisms with a high risk of being acquired when the environment is contaminated. Antibiotic-resistant bacteria are emerging rapidly around the globe creating a serious threat.

Methods

A cross-sectional study was conducted from December 2016–February 2017 at Mizan-Tepi University Teaching Hospital, Southwest Ethiopia. Samples were collected from the equipment and hospital surfaces. The isolated bacteria were checked for susceptibility by the Kirby–Bauer disc diffusion method following the standards of CLSI 2014. Health professionals and sanitary team members were included in the study which assessed the disinfection practice of objects from which samples were taken. Data were analyzed using SPSS version 20.0.

Results

A total of 201 swab samples were taken, and most bacteria were recovered from thermometer and floor consisting of 21.6% S. aureus, 19.3% CoNS, 15.9% E. coli, 14.8% Klebsiella species, 11.4% P. aeruginosa, 10.2% Proteus species, and 6.8% Serratia species. The most multidrug resistant organisms were S. aureus (79%), Klebsiella species (53.8%), CoNS (47%), and Proteus species (44.4%). Only 6.45% of health professionals disinfect their stethoscope consistently.

Conclusion

S. aureus, CoNS, and E. coli were the predominant isolates. Most isolates showed highest susceptibility to ciprofloxacin and least to ampicillin and penicillin. There is no regular sanitation and disinfection of hospital equipment and surfaces.

The uses and limitations of a hand-held germicidal ultraviolet wand for surface disinfection

The morbidity and mortality from healthcare associated infections has raised concern that conventional disinfection methods are inadequate and that other adjunct methods such as room fumigation and ultraviolet irradiation may be needed. There is also concern that these alternative methods may pose a risk to workers and patients.

OBJECTIVES

(1) Determine the efficacy of a germicidal UV-C wand for surface disinfection, (2) evaluate changing relative humidity (RH) and different target distances on bacteria kill rates, and (3) assess potential exposure concerns.

METHODS

This study investigates whether a hand-held germicidal wand can efficaciously disinfect surfaces treated with either a vegetative or spore forming bacterium and to evaluate the effect of changing environmental conditions such as relative humidity (RH), target position, and target distances on microbial kill rates.

RESULTS

Kill rate was best at 40-65% RH at a temperature range of 21-24°C. Both high and low RH interfered with the ability of UV-C to kill the vegetative microbe. In the case of the spore forming bacterium, increased surface drying time was the most significant factor increasing kill rate.

CONCLUSIONS

This research demonstrates that UV-C was efficacious under optimal conditions, a direct beam exposure, and a short target distance (12.7 cm). However, there are limitations when used in non-optimal conditions. Increased distance and indirect beam angles resulted in lower kill rates. It is also important to minimize unnecessary patient and worker exposure during its use.

A meta-analysis of the rates of Staphylococcus aureus and methicillin-resistant S aureus contamination on the surfaces of environmental objects that health care workers frequently touch

BACKGROUND

Health care workers may potentially spread Staphylococcus aureus and methicillin-resistant S aureus (MRSA) to patients by contaminated high-touch items. We aimed to determine the pooled rates of S aureus and MRSA contamination and influencing factors.

METHODS

A literature search of the PubMed, ScienceDirect, Embase, Ovid, and Scopus databases was performed. Pooled contamination rates were determined using random effect models. Subgroup and meta-regression analyses were conducted to identify factors potentially influencing the rates of S aureus and MRSA contamination. Sensitivity and publication bias analyses were performed.

RESULTS

Thirty-eight studies were included in the meta-analysis. The pooled contamination rates were 15.0% (95% confidence interval [CI], 9.8%-21.1%) for S aureus and 5.0% (95% CI, 2.7%-7.7%) for MRSA. The subgroup analyses indicated that the pooled rate of S aureus contamination was significantly higher for studies conducted in South America, in developing countries, and during 2010-2015. The pooled rate of MRSA contamination was significantly higher for studies conducted in Africa. The meta-regression analysis suggested that the pooled rate of S aureus contamination was lower for studies conducted in developed countries (odds ratio, 0.664; 95% CI, 0.509-0.867; P = .004). No bias was found in the publication of the rates of S aureus and MRSA contamination.

CONCLUSIONS

S aureus and MRSA contamination statuses of high-touch items are worrisome and should be paid greater attention. Developing country status was a risk factor for S aureus contamination.

Active efflux pump adeB is involved in multidrug resistance of Acinetobacter baumannii induced by antibacterial agents

The aim of the present study was to investigate the resistance of Acinetobacter baumannii, which was induced by cefepime (FEP), cefoperazone-sulbactam (SCF), tazobactam (TZP), levofloxacin (LEV), amikacin (AK), imipenem (IPM), and ciprofloxacin (CIP), in vitro. Multi-step drug resistance selection of 16 A. baumannii strains was performed using seven antibacterial agents (FEP, TZP, CIP, AK, IPM, SCF, and LEV). The minimum inhibitory concentration (MIC) was determined using the agar dilution method. Random amplified polymorphic DNA polymerase chain reaction was performed to analyze the genotypes and the carrying rates of aac(3)-I, aac(6')-I, ant(3)-I, aph(3)-Via, OXA-23, OXA-24, AmpC, TEM-1, metallo-β-lactamase gene (IMP), armA, rmtA, rmtB, parC, gyrA and adeB. Expression of adeB was determined using semi-quantitative reverse transcription-polymerase chain reaction (Semi-qRT-PCR). Among the 16 strains, 15 strains with drug resistance (93.8%) were obtained following in vitro induction. Notable increases (8- to 128-fold) were noted in the MIC and different genotypes were showed in RAPD of the strains before and after performing the drug resistant test. PCR data revealed significant differences (P<0.05) between the carrying rates of resistant genes before and after drug induction, with the exception of rmtA, OXA-24, TEM-1, and IMP. Significant increases were demonstrated in the comparative adeB grayscale in strains that underwent drug induction when compared with the sensitive strains (55.69±43.11% vs. 10.08±26.35%; P=0.001). Findings of the present study suggest that the active efflux pump, adeB, has an important role in multidrug resistance of the A. baumannii induced by antibacterial agents in vitro.

Cold atmospheric pressure plasma and decontamination. Can it contribute to preventing hospital-acquired infections?

Healthcare-associated infections (HCAIs) affect ∼4.5 million patients in Europe alone annually. With the ever-increasing number of 'multi-resistant' micro-organisms, alternative and more effective methods of environmental decontamination are being sought as an important component of infection prevention and control. One of these is the use of cold atmospheric pressure plasma (CAPP) systems with clinical applications in healthcare facilities. CAPPs have been shown to demonstrate antimicrobial, antifungal and antiviral properties and have been adopted for other uses in clinical medicine over the past decade. CAPPs vary in their physical and chemical nature depending on the plasma-generating mechanism (e.g. plasma jet, dielectric barrier discharge, etc.). CAPP systems produce a 'cocktail' of species including positive and negative ions, reactive atoms and molecules (e.g. atomic oxygen, ozone, superoxide and oxides of nitrogen), intense electric fields, and ultraviolet radiation (UV). The effects of these ions have been studied on micro-organisms, skin, blood, and DNA; thus, a range of possible applications of CAPPs has been identified, including surface decontamination, wound healing, biofilm removal, and even cancer therapy. Here we evaluate plasma devices, their applications, mode of action and their potential role specifically in combating HCAIs on clinical surfaces.

Potent bactericidal efficacy of copper oxide impregnated non-porous solid surfaces

BACKGROUND

The role of fomites and the environment in nosocomial infections is becoming widely recognized. In this paper we discuss the use of Cupron copper oxide impregnated non-porous solid surface in the hospital setting and present in vitro testing data via USA Environmental Protection Agency (EPA) approved testing protocols that demonstrate the efficacy of these products to assist in reduction in environmental contamination and potentially nosocomial infections.

RESULTS

The two countertops tested passed all the acceptance criteria by the EPA (>99.9% kill within 2 hours of exposure) killing a range of bacterial pathogens on the surface of the countertops even after repeated exposure of the countertops to the pathogen, and multiple wet and dry abrasion cycles.

CONCLUSIONS

Cupron enhanced EOS countertops thus may be an important adjunct to be used in hospital settings to reduce environmental bioburden and potentially nosocomial infections.

Computer keyboard covers impregnated with a novel antimicrobial polymer significantly reduce microbial contamination

BACKGROUND

Contaminated computer keyboards have been acknowledged as a potential source for bacterial transmission between health care providers and patients. Biosafe HM 4100 is an antimicrobial polymer that can be incorporated into the polyurethane material used to make keyboard covers. This study aimed to determine whether plastic keyboard covers containing HM 4100 effectively minimize the survival of bacterial species commonly present on health care environmental surfaces.

METHODS

Polyurethane material that contained 0.5% HM 4100, 1% HM 4100, and 1% HM 4100 with spray coating of 1% HM 4100 were tested. In 2 separate experiments, the surfaces of test materials were inoculated with suspensions of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecalis (VREF), Escherichia coli, or Pseudomonas aeruginosa. Viability was assessed on the materials at 0, 10, 30, 60, 120, and 240 minutes after inoculation.

RESULTS

Maximum reductions in viability were observed for all 4 organisms at the longest tested time period on each test material. Mean reductions on the 0.5% HM 4100 material at 240 minutes were 99.99% for E coli, 97.8% for MRSA, 95.0% for VREF, and 92.1% for P aeruginosa. Mean reductions on the 1% HM 4100 at 120 minutes were 99.9% for VREF, 99.9% for MRSA, 99.9% for P aeruginosa, and 99.5% for E coli. Mean reductions on the 1% HM 4100 plus spray coating at 30 minutes were 99.9% for E coli, 99.8% for VREF, 98.8% for P aeruginosa, and 97.2% for MRSA.

CONCLUSIONS

Incorporation of the HM 4100 antimicrobial polymer into polyurethane keyboard material may reduce the hand carriage of bacteria between health care providers and patients.

Comparison of PCR/electron spray ionization-time-of-flight-mass spectrometry versus traditional clinical microbiology for active surveillance of organisms contaminating high-use surfaces in a burn intensive care unit, an orthopedic ward and healthcare workers

Background

Understanding nosocomial pathogen transmission is restricted by culture limitations. Novel platforms, such as PCR-based electron spray ionization-time-of-flight-mass spectrometry (ESI-TOF-MS), may be useful as investigational tools.

Methods

Traditional clinical microbiology (TCM) and PCR/ESI-TOF-MS were used to recover and detect microorganisms from the hands and personal protective equipment of 10 burn intensive care unit (ICU) healthcare workers providing clinical care at a tertiary care military referral hospital. High-use environmental surfaces were assessed in 9 burn ICU and 10 orthopedic patient rooms. Clinical cultures during the study period were reviewed for pathogen comparison with investigational molecular diagnostic methods.

Results

From 158 samples, 142 organisms were identified by TCM and 718 by PCR/ESI-TOF-MS. The molecular diagnostic method detected more organisms (4.5 ± 2.1 vs. 0.9 ± 0.8, p < 0.01) from 99% vs. 67% of samples (p < 0.01). TCM detected S. aureus in 13 samples vs. 21 by PCR/ESI-TOF-MS. Gram-negative organisms were less commonly identified than gram-positive by both methods; especially by TCM. Among all detected bacterial species, similar percentages were typical nosocomial pathogens (18-19%) for TCM vs. PCR/ESI-TOF-MS. PCR/ESI-TOF-MS also detected mecA in 112 samples, vanA in 13, and KPC-3 in 2. MecA was associated (p < 0.01) with codetection of coagulase negative staphylococci but not S. aureus. No vanA was codetected with enterococci; one KPC-3 was detected without Klebsiella spp.

Conclusions

In this pilot study, PCR/ESI-TOF-MS detected more organisms, especially gram-negatives, compared to TCM, but the current assay format is limited by the number of antibiotic resistance determinants it covers. Further large-scale assessments of PCR/ESI-TOF-MS for hospital surveillance are warranted.

Fighting nosocomial infections with biocidal non-intrusive hard and soft surfaces

Approximately 7 million people worldwide acquire a healthcare associated infection each year. Despite aggressive monitoring, hand washing campaigns and other infection control measures, nosocomial infections (NI) rates, especially those caused by antibiotic resistant pathogens, are unacceptably high worldwide. Additional ways to fight these infections need to be developed. A potential overlooked and neglected source of nosocomial pathogens are those found in non-intrusive soft and hard surfaces located in clinical settings. Soft surfaces, such as patient pyjamas and beddings, can be an excellent substrate for bacterial and fungal growth under appropriate temperature and humidity conditions as those present between patients and the bed. Bed making in hospitals releases large quantities of microorganisms into the air, which contaminate the immediate and non-immediate surroundings. Microbes can survive on hard surfaces, such as metal trays, bed rails and door knobs, for very prolonged periods of time. Thus soft and hard surfaces that are in direct or indirect contact with the patients can serve as a source of nosocomial pathogens. Recently it has been demonstrated that copper surfaces and copper oxide containing textiles have potent intrinsic biocidal properties. This manuscript reviews the recent laboratory and clinical studies, which demonstrate that biocidal surfaces made of copper or containing copper can reduce the microbiological burden and the NI rates.

Bacterial contamination of clothes and environmental items in a third-level hospital in Colombia

Objective. This study evaluates the bacterial contamination rate of items in the hospital setting that are in frequent contact with patients and/or physicians. By determining the bacterial species and the associated antibiotic resistance that patients are exposed to. Methods. Hospital-based cross-sectional surveillance study of potential bacterial reservoirs. Cultures from 30 computer keyboards, 32 curtains, 40 cell phones, 35 white coats, and 22 ties were obtained. Setting. The study was conducted an urban academic 650-bed teaching hospital providing tertiary care to the city of Medellin, Colombia. Results. In total, 235 bacterial isolates were obtained from 159 surfaces sampled. 98.7% of the surfaces grew positive bacterial cultures with some interesting resistance profiles. Conclusion. There are significant opportunities to reduce patient exposure to frequently pathogenic bacteria in the hospital setting; patients are likely exposed to many bacteria through direct contact with white coats, curtains, and ties. They may be exposed to additional bacterial reservoirs indirectly through the hands of clinicians, using computer keyboards and cell phones.

Recovery of staphylococci from computer keyboards in a veterinary medical centre and the effect of routine cleaning

Computers play a vital role in veterinary clinics for grading, examining results, updating records, giving discharge instructions and maintaining billing information. Few studies have documented the degree of contamination or practical methods to disinfect computer equipment within the veterinary clinic setting. The intent of the present study was to characterise the frequency of recovery of Staphylococcus species from computer keyboards from a veterinary teaching hospital setting and to evaluate the effect of daily cleaning. From three keyboards in a treatment area, three in a dermatology area and one in office 70 environmental samples were cultured for Staphylococcus. As an indirect measure to assess cleanliness, samples were collected and tested using the 3M Clean-Trace Luminometer (relative light units [RLU]). Of the 25 Staphylococcus recovered 13 were Staphylococcus species, seven Staphylococcus pseudintermedius, four Staphylococcus aureus and one mixed colony of both Staphylococcus species and S pseudintermedius. The median RLU was 2098 (range 132 to 11,590). Routine cleaning decreased the recovering of Staphylococcus and the RLU values. In summary, the study results demonstrate the value of routine cleaning of keyboards and the need for on-going and regular education of staff and students about good hand hygiene.

The risks and benefits of chemical fumigation in the health care environment

Fumigation of hospital rooms with high concentrations of toxic chemicals has been proposed to reduce microbial agents on hospital surfaces and to control infections. Chemical fumigation has been used effectively in other areas, such as building decontamination after bioterrorism events, in agriculture, and in residential structures. However, even in these situations, there have been incidents where fumigants have escaped, causing illness and death to exposed workers and the public. Before expanding the use of a potentially hazardous technology in areas where there are vulnerable individuals, it is important to fully weigh benefits and risks. This article reviews the effectiveness of fumigation as a method of inactivating microbes on environmental surfaces and in reducing patient infection rates against the potential risks. Peer-reviewed literature, consensus documents, and government reports were selected for review. Studies have demonstrated that fumigation can be effective in inactivating microbes on environmental surfaces. However, the current consensus of the infection control community is that the most important source of patient infection is direct contact with health care workers or when patients auto-infect themselves. Only one peer-reviewed, before-after study, at one hospital reported a significant reduction in infection rates following chemical fumigation. The limitations of this study were such that the authors acknowledged that they could not attribute the rate reduction to the fumigation intervention. A serious concern in the peer-reviewed literature is a lack of evidence of environmental monitoring of either occupational or non-occupational exposures during fumigation. Currently, there are neither consensus documents on safe fumigation exposure levels for vulnerable bedridden patients nor sampling methods with an acceptable limit of detection for this population. Until additional peer-reviewed studies are published, demonstrating significant reductions in patient infection rates following chemical fumigation and consensus guidance on the safe exposure levels and monitoring methods, chemical fumigation in health care should be conducted only in the most stringently controlled research settings.

Difference in imipenem, meropenem, sulbactam, and colistin nonsusceptibility trends among three phenotypically undifferentiated Acinetobacter baumannii complex in a medical center in Taiwan, 1997-2007

BACKGROUND

To determine whether the susceptibilities and the trends of nonsusceptibility of imipenem, meropenem, sulbactam, and colistin differed among Acinetobacter baumannii, Acinetobacter genomic species 3 (AGS 3), and Acinetobacter genomic species 13TU (AGS 13TU) over 11 years.

METHODS

A total of 1,039 nonduplicate blood isolates of A baumannii complex from bacteremic patients between 1997 and 2007 were collected at Taipei Veterans General Hospital and were identified to the species level using a multiplex polymerase chain reaction method and sequence analysis of 16S-23S intergenic spacer. The minimal inhibitory concentrations of antibiotics were determined by the agar dilution method.

RESULTS

The nonsusceptibility rates of carbepenems and sulbactam were highest in A baumannii, which also showed a trend toward increasing rate of carbapenems nonsusceptibility over the 11-year period of the study. AGS 13TU had the highest nonsusceptible rate to colistin, comparably increasing trend of carbapenem nonsusceptiblity as that of A baumannii, and is the only species with increasing sulbactam nonsusceptibility. AGS 3 had the lowest rate of nonsusceptibility to all four antimicrobial agents.

CONCLUSION

Although A baumannii had the highest nonsusceptibility rate to imipenem, meropenem, and sulbactam over the years, the higher rate of colistin nonsusceptibility and the emergence of nonsusceptibility of carbapenems and sulbactam in AGS 13TU suggested that this species might cause a great problem in the near future.

Are laptop ventilation-blowers a potential source of nosocomial infections for patients?

Inadequately performed hand hygiene and non-disinfected surfaces are two reasons why the keys and mouse-buttons of laptops could be sources of microbial contamination resulting consequently in indirect transmission of potential pathogens and nosocomial infections. Until now the question has not been addressed whether the ventilation-blowers in laptops are actually responsible for the spreading of nosocomial pathogens. Therefore, an investigational experimental model was developed which was capable of differentiating between the microorganisms originating from the external surfaces of the laptop, and from those being blown out via the ventilation-blower duct. Culture samples were taken at the site of the external exhaust vent and temperature controls were collected through the use of a thermo-camera at the site of the blower exhaust vent as well as from surfaces which were directly exposed to the cooling ventilation air projected by the laptop. Control of 20 laptops yielded no evidence of microbial emission originating from the internal compartment following switching-on of the ventilation blower. Cultures obtained at the site of the blower exhaust vent also showed no evidence of nosocomial potential. High internal temperatures on the inner surfaces of the laptops (up to 73°C) as well as those documented at the site of the blower exhaust vent (up to 56°C) might be responsible for these findings.

Current views of health care design and construction: practical implications for safer, cleaner environments

Infection preventionists (IP) play an increasingly important role in preventing health care-associated infection in the physical environment associated with new construction or renovation of health care facilities. The Guidelines for Design and Construction of Hospital and Healthcare Facilities, 2010, formerly known as "AIA Guidelines" was the origin of the "infection control risk assessment" now required by multiple agencies. These Guidelines represent minimum US health care standards and provide guidance on best practices. They recognize that the built environment has a profound affect on health and the natural environment and require that health care facilities be designed to "first, do no harm." This review uses the Guidelines as a blueprint for IPs' role in design and construction, updating familiar concepts to the 2010 edition with special emphasis on IP input into design given its longer range impact on health care-associated infection prevention while linking to safety and sustainability. Section I provides an overview of disease transmission risks from the built environment and related costs, section II presents a broad view of design and master planning, and section III addresses the detailed design strategies for infection prevention specifically addressed in the 2010 Facility Guidelines Institute edition.

The environment as a factor in methicillin-resistant Staphylococcus aureus transmission

In recent years, methicillin-resistant Staphylococcus aureus (MRSA) has become a leading cause of infectious disease morbidity and mortality in the United States. The epidemiology of the organism has changed, with novel strains emerging in the community among individuals lacking any healthcare contact. Although direct human-to-human transmission via skin contact is one way for this organism to spread, transmission via environmental contamination of fomites or through air are other potential ways that the organism can be acquired. As such, an improved understanding of MRSA transmission is needed to implement maximally effective control and prevention interventions. We review the research documenting the role of the environment in MRSA spread.