Standard Disinfection Research Articles

Fractional–Order Modeling and Control of COVID-19 with Shedding Effect

A fractional order COVID-19 model consisting of six compartments in Caputo sense is constructed. The indirect transmission of the virus through susceptible populations by the shedding effect is studied. Equilibrium solutions are calculated, and basic reproduction ratio (that depends both on direct and indirect mode of transmission), existence and uniqueness, as well as stability analysis of the solution of the model, are studied. The paper studies the effect of optimal control policy applied to shedding effect. The control is the observation of standard hygiene practices and chemical disinfectants in public spaces. Numerical simulations are carried out to support the analytic result and to show the significance of the fractional order from the biological viewpoint.

A systematic review of the germicidal effectiveness of ultraviolet disinfection across high-touch surfaces in the immediate patient environment.

There is not yet a consensus regarding the in-use effectiveness of ultraviolet irradiation (UV-C) as a supplementary tool for terminal room disinfection. To summarize and evaluate literature detailing the germicidal effectiveness of UV-C disinfection on high-touch surfaces in the patient environment. A literature search was carried out utilizing PRISMA guidelines. Studies were included if intervention included UV-C after standard room disinfection in hospital rooms evaluated microbiologically by surface type. Twelve records met our criteria for inclusion. Studies predominantly focused on terminal disinfection of patient rooms, including five reports carried out in isolation rooms and three studies including operating room (OR) surfaces. Bedrails, remote controls, phones, tray tables, assist rails, floors, and toilets were the most commonly reported surfaces. Across study designs, surfaces, and room types, flat surfaces tended to showcase UV-C effectiveness best, particularly isolation room floors. In contrast, handheld surfaces (i.e., bed controls and assist bars) tended to show reduced efficacies (81-93%). In the OR, complex surfaces similarly demonstrated reduced UV-C effectiveness. Bathroom surfaces demonstrated 83% UV-C effectiveness overall, with surface characteristics uniquely impacted depending on the room type. Isolation room studies tended to include effectiveness comparison with standard treatment, reporting UV-C superiority most of the time. This review highlights the enhanced effectiveness of UV-C surface disinfection over standard protocols across various study designs and surfaces. However, surface and room characteristics do appear to play a role in the level of bacterial reduction.

Disinfection of incubators in neonatal intensive care units: impact of steam pulverization on bacterial colonization

BackgroundIn neonatal intensive care units (NICUs), neonates requiring medical care after birth, including very vulnerable preterm infants, are housed in incubators. Previous studies have reported that the standard chemical disinfection measures used to disinfect these incubators are insufficient to eradicate contaminating bacteria, leading to a worrying infectious risk for preterm neonates. This study aimed to evaluate the efficacy of a disinfection method based on steam pulverization to eradicate the persistent bacterial contamination in such incubators.MethodsIn a tertiary NICU, 20 incubators were monitored qualitatively for bacterial contamination at five different sites (the rubber grommet, the left door handles, the temperature adjustment button, the mattress and the scale) using a culture method at three times: before and after steam pulverization then 24 h after turning on and housing a new neonate. Clinical data of neonates housed in each incubator were retrieved from the medical records to identify potential occurrence of late onset sepsis (LOS).ResultsJust after steam pulverization, only two incubators were free from bacteria. Before disinfection 87% of all the samples were contaminated compared to 61% after disinfection. After 24 h, the proportion of contaminated samples reached 85%. Mattresses and scales were the most frequently contaminated incubator sites with respectively 90% and 80% positive samples after disinfection compared to 100% and 90% before disinfection. Coagulase-negative staphylococci, Enterococcus, Enterobacteria and Bacillus resisted disinfection and were identified on respectively 90%, 20%, 5% and 45% of incubators just after disinfection. Three preterm neonates developed LOS after being housed in a disinfected incubator but the bacterial species involved have not been identified in their incubator after disinfection. In two cases, the bacterium had been isolated from the mattress 24 h after housing the infected patient.ConclusionSteam pulverization is not sufficient to eradicate bacterial contamination of incubators. These results highlight the urgent need for an effective disinfection method, especially for mattresses that are in constant contact with patients. In parallel, new incubator designs and mattress protections must be developed.

Implementation of an Environmental Cleaning Protocol in Hospital Critical Areas Using a UV-C Disinfection Robot.

Improving the cleaning and disinfection of high-touch surfaces is one of the core components of reducing healthcare-associated infections. The effectiveness of an enhanced protocol applying UV-C irradiation for terminal room disinfection between two successive patients was evaluated. Twenty high-touch surfaces in different critical areas were sampled according to ISO 14698-1, both immediately pre- and post-cleaning and disinfection standard operating protocol (SOP) and after UV-C disinfection (160 sampling sites in each condition, 480 in total). Dosimeters were applied at the sites to assess the dose emitted. A total of 64.3% (103/160) of the sampling sites tested after SOP were positive, whereas only 17.5% (28/160) were positive after UV-C. According to the national hygienic standards for health-care setting, 9.3% (15/160) resulted in being non-compliant after SOP and only 1.2% (2/160) were non-compliant after UV-C disinfection. Operation theaters was the setting that resulted in being less compliant with the standard limit (≤15 colony-forming unit/24 cm2) after SOP (12%, 14/120 sampling sites) and where the UV-C treatment showed the highest effectiveness (1.6%, 2/120). The addition of UV-C disinfection to the standard cleaning and disinfection procedure had effective results in reducing hygiene failures.

SG-APSIC1111: Abstract management services for the sterilization of single-use medical supplies

Objectives: Single-use medical supplies are usually expensive, resulting in excess costs for hospitals and patients. Reusing single-use medical devices by resterilization or reprocessing has thus been enacted. We compared the cost of resterilizing single-use medical supplies with the cost of new purchases to reduce the unnecessary resterilization of medical supplies. Methods: The central sterile supply department (CSSD) listed single-use medical supplies that were sent for resterilization. Policies and guidelines for reusing or resterilizing single-use medical supplies were established following the standards for disinfection and sterilization. The costs of the resterilizing process for single-use medical supplies were compared with the expenses of new purchases of those medical supplies. Results: In 2019, many medical supplies were resterilized, and the resterilization of single-use devices cost up to 2,352,270 Thai baht (US $68,340). Since this project was implemented in fiscal year 2020 (October 1, 2019–September 30, 2020), the resterilization of medical supplies has decreased, and the cost of resterilization has decreased to 1,356,280 Thai baht (US $40,557), leading to a saving of 995,990 Thai baht (US $29,783, or 42% of the resterilization cost in 2019). The CSSD proposed a resterilization policy in which resterilization for reuse must be done for medical supplies and/or devices that cost ≥1,000 Thai baht (US $30). Conclusions: Although this project did not reach the target outcome of 100% reduction, the outcome was consistent with the aims of the project. The cost of resterilization of single-use medical supplies can be reduced, and a resterilization system can be developed that assures safety and effectiveness to both service providers and patients.

Mitigating Endoscope-Associated Infections: Revised ANSI/AAMI Standards and New Duodenoscope Surveillance Antimicrobial Sampling and Culturing Protocols

Article| January 2023 Mitigating Endoscope-Associated Infections: Revised ANSI/AAMI Standards and New Duodenoscope Surveillance Antimicrobial Sampling and Culturing Protocols Uday Jain, BSEE, MD, PhD, FASA Uday Jain, BSEE, MD, PhD, FASA Search for other works by this author on: This Site PubMed Google Scholar ASA Monitor January 2023, Vol. 87, 29. https://doi.org/10.1097/01.ASM.0000911792.39689.52 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Search Site Citation Uday Jain; Mitigating Endoscope-Associated Infections: Revised ANSI/AAMI Standards and New Duodenoscope Surveillance Antimicrobial Sampling and Culturing Protocols. ASA Monitor 2023; 87:29 doi: https://doi.org/10.1097/01.ASM.0000911792.39689.52 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll PublicationsASA Monitor Search Advanced Search Topics: age-related cognitive decline, american national standards institute, antimicrobials, duodenoscopes, endoscopes, infections, surveillance, medical Anesthesiologists provide anesthesia for numerous endoscopy procedures. They also perform bronchoscopy and other endoscopies. There are recent developments in mitigating endoscopy-associated infections. Carbapenem-resistant Enterobacteriaceae (CRE) infections, which are resistant to multiple antibiotics, have been traced to duodenal endoscopy, cystoscopy, and ureteroscopy (Am J Infect Control 2016;44:1032-6). These cases had all followed standard disinfection protocols. The outbreaks were traced to difficulty sterilizing complex shapes or materials, such as the hinge of side-viewing duodenoscopes. As a result of these outbreaks, new sterilization standards have been published by the American National Standards Institute (ANSI)/Association for the Advancement of Medical Instrumentation (AAMI) (ANSI/AAMI ST91:2021; asamonitor.pub/3DEYQnI). Additionally, the FDA and the CDC published new surveillance antimicrobial surveillance guidelines (asamonitor.pub/3Qgqiwq). The FDA recommends transitioning to fully disposable duodenoscopes (Clin Gastroenterol Hepatol 2020;18:2108-2117) or using endoscopes with disposable components. This guidance includes developing schedules for routine inspection and... You do not currently have access to this content.

Life Cycle Assessment of Reusable and Disposable Cystoscopes: A Path to Greener Urological Procedures

BackgroundThe environmental impact of reusable and disposable devices is unclear; reuse is expected to reduce the carbon footprint, but the environmental impact of reprocessing of reusable devices is increasingly being questioned. ObjectiveThe aim was to provide the first rigorous life cycle assessment of reusable and disposable flexible cystoscopes. Design, setting, and participantsWe performed a life cycle assessment of reusable flexible cystoscopes and the aS4C single-use cystoscope (aScope; Ambu, Ballerup, Denmark). For the aScope, the complete lifespan of the scope was evaluated, including raw material extraction, material formulation, component production, product assembly, distribution, transportation after use, and final disposal. For reusable cystoscopes, we limited our analysis to their reprocessing, using a model consisting of standard high-level disinfection with peracetic acid. The environmental impact was evaluated by an independent third-party consulting company APESA (Technopole Hélioparc, Pau, France) dedicated to such risk assessments. Outcome measurements and statistical analysisThe environmental footprint of both cystoscopes was assessed using five environmental impact categories, namely, climate change, mineral resource depletion, ecotoxicity, acidification, and eutrophication. To perform the life cycle assessment, Simapro v9.3.3 software was used and the Ecoinvent v3.5 database was employed as the primary life cycle inventory database. A Monte Carlo analysis was used to account for the inherent uncertainty in life cycle inventory data and the variability in material and energy consumption for each type of flexible cystoscope. Results and limitationsBy only comparing the disinfection reprocessing of reusable cystoscopes with the complete lifespan of the single-use cystoscope, the use of the aScope would allow a reduction of at least 33% in the climate change category, 50% in the mineral resources’ depletion category, 51% in the ecotoxicity category, 71% in the acidification category, and 49% in the eutrophication category. Our results cannot be generalized to all health care facilities as we studied only one type of reprocessing method and one disposable flexible cystoscope. ConclusionsDisinfection reprocessing of reusable cystoscopes was found to have a significantly larger environmental footprint and impact than the whole lifespan of the single-use cystoscope aScope. Patient summaryUsing a cradle-to-grave life cycle analysis, we showed that the environmental footprint of a flexible cystoscopy procedure can be reduced by using a disposable cystoscope instead of a reusable cystoscope.

Mpox: What Practicing Gastroenterologists Need to Know

Mpox: What Practicing Gastroenterologists Need to Know

Infection control measures at maternity and children hospital and data analysis

Nosocomial Infections are the infections that are neither at incubating state nor present at the time of admission. They are greatly associated with Surgical procedures and Invasive Medical Devices and hence OTs and ICUs are known as ‘Hot Zones’ and Gram Negative and Gram-positive organisms are responsible. Hence, regular surveillance of these areas remains the mainstay to monitor the raising trend of nosocomial infections. To find out the prevalence of Bacteria and Bacterial load in Pre and Post fumigation swabs from various areas of Maternity and Children hospital like OTs, Patient Ward, Labor ward and NICUs and to test the effectiveness of the standard disinfectants. The swabs were collected from different areas of MGM Maternity and Children Hospital, Kalamboli Mumbai The swabs were further processed and organisms were identified using standard Microbiological procedures. The standard disinfectants were tested using Kelsey-Sykes Capacity test, and they “Passed” the test. Out of the total Pre fumigation swabs collected, growth was seen in 15% of the swabs while in Post fumigation swabs 3% of growth was seen. In places like Minor OT, Septic OT, Labor Room, Waiting Room a higher value of Chi-square test statistics indicated a statistically significant association between fumigation and growth of microorganisms. Majorly non-pathogenic organism like Bacillus was isolated followed by CoNS and few . Hence this indicates significant reduction in growth of microorganisms in majority of the areas of post fumigation swabs indicating following of proper infection control procedures. This study describes the profile of Bacterial Load in high-risk areas of Maternity and Children Hospital. Pre and post fumigation swabs were tested from high-risk areas including Minor OT, Major OT, Septic OT, Female Ward, Recovery Room, PNC, NICU. Also, suggestions were made to incorporate air sampling methods for better assessments. The knowledge of these findings and appropriate corrective measures can greatly impact the health of neonates as well as the mothers.

DETECTION OF POTENTIAL PATHOGENIC BACTERIA IN SELECTED PUBLIC SWIMMING POOLS: PUBLIC HEALTH IMPLICATIONS

The contamination of recreational waters poses public health risk to users as a result of potential spread of infectious diseases. Hence there is need for continuous monitoring of swimming pools and other recreational waters to mitigate the spread of infections. This study was initiated to investigate the presence of pathogen bacteria of significant public health implications in public swimming pool waters. Water samples were collected from selected public swimming pools in Benin City and transported to the laboratory for microbial analysis. One ml of water sample was spread on the following specific media M endo agar, Chromocult agar and Mannitol Salt agar for the isolation of Total Coliforms Escherichia coli and Staphylococcus aureus respectively. Among the 12 swimming pool surveyed and examined, Staphylococcus aureus was detected in 42% (5/12) of samples while E. coli was detected in 67% (8/12) of samples. Coliform was found in 75% (9/12) of the samples. Analysis of respondent questionnaire reveals that 67% (8/12) of swimming pool managers disinfect the swimming pool water weekly while about 17% (2/12) disinfect the swimming pool daily. In general, a range of 2 20 bathers use each pool per day. Also site 6 has the highest number of bathers with bathers ranging from 15 20 bathers per day. The detection of Staphlococcus aureus in the present study suggests poor pool compliance to disinfection standards and poor bathers hygiene. Also, the detection of E.coli and total coliform also indicates fecal contamination or contamination from environmental sources. There is need for incessant monitoring of recreational facilities in order to mitigate the risk of spread of infections in recreational water.

Bacteriophage-based decontamination to control environmental colonization by Staphylococcus capitis in neonatal intensive care units: An in vitro proof-of-concept.

In neonatal intensive care units (NICUs), the standard chemical-based disinfection procedures do not allow a complete eradication of pathogens from environmental surfaces. In particular, the clone Staphylococcus capitis NRCS-A, a significant pathogen in neonates, was shown to colonize neonatal incubators. The aim of this study was to evaluate the in vitro effect of a bacteriophage cocktail on NRCS-A eradication. Three bacteriophages were isolated, genetically characterized and assessed for their host range using a collection of representative clinical strains (n=31) belonging to the clone NRCS-A. The efficacy of a cocktail including these three bacteriophages to eradicate the reference strain S. capitis NRCS-A CR01 was determined in comparison or in combination with the chemical disinfectant Surfanios Premium on either dry inoculum or biofilm-embedded bacteria. The emergence of bacterial resistance against the bacteriophages alone or in cocktail was evaluated by growth kinetics. The three bacteriophages belonged to two families and genera, namely Herelleviridae/Kayvirus for V1SC01 and V1SC04 and Rountreeviridae/Andhravirus for V1SC05. They were active against 17, 25 and 16 of the 31 tested strains respectively. Bacteriophage cocktails decreased the bacterial inoculum of both dry spots and biofilms, with a dose dependent effect. The sequential treatment with bacteriophages then Surfanios Premium did not show enhanced efficacy. No bacterial resistance was observed when using the bacteriophage cocktail. This study established a proof-of-concept for the use of bacteriophages to fight against S. capitis NRCS-A. Further investigations are needed using a larger bacterial collection and in real-life conditions before being able to use such technology in NICUs.

An Enhanced Strategy for Daily Disinfection in Acute Care Hospital Rooms

Environmental contamination is a source of transmission between patients, health care practitioners, and other stakeholders in the acute care setting. To compare the efficacy of an enhanced daily disinfection strategy vs standard disinfection in acute care hospital rooms. This randomized clinical trial (RCT) was conducted in acute care hospital rooms at Duke University Hospital in Durham, North Carolina, from November 2021 to March 2022. Rooms were occupied by patients with contact precautions. Room surfaces (bed rails, overbed table, and in-room sink) were divided into 2 sides (right vs left), allowing each room to serve as its own control. Each side was randomized 1:1 to the intervention group or control group. The intervention was a quaternary ammonium, salt-based, 24-hour continuously active germicidal wipe. It was applied in addition to routine disinfection for the intervention group. The control group received no intervention beyond routine disinfection. The primary outcome was the total contamination, measured in colony-forming units (CFUs) on the bed rails, overbed table, and sink on study day 1. The secondary outcomes were the proportion of sample areas with positive test results for clinically important pathogens, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and carbapenem-resistant Enterobacteriaceae; the similarity in baseline contamination between sample area sides on study day 0 before application of the intervention, and the proportion of sample areas with removed UV luminescent gel on study day 1. A total of 50 study rooms occupied by 50 unique patients (median [IQR] age, 61 [45-69] years; 26 men [52%]) with contact precautions were enrolled. Of these patients, 41 (82%) were actively receiving antibiotics, 39 (78%) were bedridden, and 28 (56%) had active infections with study-defined clinically important pathogens. On study day 1, the median (IQR) total CFUs for the intervention group was lower than that for the control group (3561 [1292-7602] CFUs vs 5219 [1540-12 364] CFUs; P = .002). On study day 1, the intervention side was less frequently contaminated with patient-associated clinically important pathogens compared with the control side of the room (4 [14%] vs 11 [39%]; P = .04). Results of this RCT demonstrated that a quaternary ammonium, salt-based, 24-hour continuously active germicidal wipe decreased the environmental bioburden in acute care hospital rooms compared with routine disinfection. The findings warrant large-scale RCTs to determine whether enhanced daily disinfection strategies can decrease patient acquisition and adverse patient outcomes. ClinicalTrials.gov Identifier: NCT05560321.

Effects of Various Disinfection Methods on the Material Properties of Silicone Dental Impressions of Different Types and Viscosities.

There is an ongoing search for novel disinfection techniques that are not only effective, cheap, and convenient, but that also do not have adverse effects on the properties of dental impressions. We compared the effects of various methods (UVC, gaseous ozone, commercial solution, and spray) on the dimensional change, tensile strength, and hardness of silicone impressions. Moreover, as a secondary aim, we performed a statistical comparison of the properties of nondisinfected addition (Panasil Putty Soft, Panasil monophase Medium, Panasil initial contact Light) and condensation silicones (Zetaplus Putty and Oranwash L), as well as a comparison of materials of various viscosities (putty, medium-bodied, and light-bodied). Our results revealed that addition silicones had higher dimensional stability, tensile strength, and Shore A hardness compared to condensation silicones. Both traditional (immersion and spraying) and alternative methods of disinfection (UVC and ozone) had no significant impact on the tensile properties and dimensional stability of the studied silicones; however, they significantly affected the hardness, particularly of Oranwash L. Our study demonstrated that, similarly to standard liquid disinfectants, both UVC and ozone do not strongly affect the material properties of most silicones. However, before recommendation, their usefulness for each individual material should be thoroughly evaluated.

Efficacy of Ultraviolet Radiations against Coronavirus, Bacteria, Fungi, Fungal Spores and Biofilm

Ultra-violet (UV) C (200–280 wavelength) light has long been known for its antimicrobial and disinfecting efficacy. It damages DNA by causing the dimerization of pyrimidines. A newly designed technology (MUVi-UVC; Mobile UV Innovations Pty Ltd., Melbourne, VIC, Australia) that emits UVC at 240 nm is composed of an enclosed booth with three UVC light stands each with four bulbs, and has been developed for disinfecting mobile medical equipment. The aim of this project was to examine the spectrum of antimicrobial activity of this device. The experiments were designed following ASTM E1052-20, EN14561, BSEN14476-2005, BSEN14562-2006 and AOAC-Official-Method-966.04 standards for surface disinfection after drying microbes on surfaces. The disinfection was analyzed using Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (6294), Candida auris (CBS 12373), spores of Aspergillus niger (ATCC 16404), coronavirus (SARS-CoV-2 surrogate ATCC VR-261) as well as a methicillin-resistant Staphylococcus aureus (SA31), a carbapenem- and polymyxin-resistant Pseudomonas aeruginosa (PA219), Escherichia coli K12 (ATCC 10798) and Salmonella typhi (ATCC 700730). The parameters of time, the number of lights and direction of the sample facing the lights were examined. The MUVi-UVC was able to kill 99.999% of all of the tested bacteria, fungi, coronavirus and bacteria in the biofilms if used for 5 min using all three lights in the setup with the glass slides in a vertical position. However, for fungal spores, 30 min were required to achieve 99.999% killing. There was a small but insignificant effect of having the surface horizontally or vertically aligned to the UV lights. Therefore, this UVC device is an effective technology to disinfect medical devices.

Combating the Fear of Infection in the Built Environment: The Ghana Communication Technology University (GCTU) Experience during Corona Virus Pandemic

Following a realization that staff and students in a Ghanaian public university were fearful of getting infected with COVID-19 due to their mistrust of the cleanliness of the campus environment, this study examined the built infrastructure cleaning and disinfection strategies adopted by the university during the COVID-19 pandemic, as well as the role played by the Facilities Manager in ensuring adherence to standard cleaning and disinfection practices. The objective was thus two-fold: first, to provide comprehensive information to all the University's stakeholders regarding the state of cleanliness of the campus environment, and secondly, to identify any possible lapses and make recommendations for improvement. The study adopted a direct observation approach to collect and analyse data, which revealed that deep cleaning approaches were adopted during the COVID-19 pandemic era. It is an extremely comprehensive cleaning exercise beyond basic cleaning, with detailed importance, and focuses on forgotten corners where dirt and dust hide. The study also revealed that the University's facility manager lacked a pre-disinfection plan, disinfection plan, and post-disinfection plan, all required to ensure adherence to standard cleaning and disinfection practices. The study thus recommends implementing some strategies and interventions to ensure the sustenance of a clean environment in the University and allay peoples' fear of contracting COVID-19 and other infections while using the University's facilities.

Tolerance of biofilm of a carbapenem-resistant Klebsiella pneumoniae involved in a duodenoscopy-associated outbreak to the disinfectant used in reprocessing

BackgroundOne possible transmission route for nosocomial pathogens is contaminated medical devices. Formation of biofilms can exacerbate the problem. We report on a carbapenemase-producing Klebsiella pneumoniae that had caused an outbreak linked to contaminated duodenoscopes. To determine whether increased tolerance to disinfectants may have contributed to the outbreak, we investigated the susceptibility of the outbreak strain to disinfectants commonly used for duodenoscope reprocessing. Disinfection efficacy was tested on planktonic bacteria and on biofilm.MethodsDisinfectant efficacy testing was performed for planktonic bacteria according to EN standards 13727 and 14561 and for biofilm using the Bead Assay for Biofilms. Disinfection was defined as ≥ 5log10 reduction in recoverable colony forming units (CFU).ResultsThe outbreak strain was an OXA-48 carbapenemase-producing K. pneumoniae of sequence type 101. We found a slightly increased tolerance of the outbreak strain in planktonic form to peracetic acid (PAA), but not to other disinfectants tested. Since PAA was the disinfectant used for duodenoscope reprocessing, we investigated the effect of PAA on biofilm of the outbreak strain. Remarkably, disinfection of biofilm of the outbreak strain could not be achieved by the standard PAA concentration used for duodenoscope reprocessing at the time of outbreak. An increased tolerance to PAA was not observed in a K. pneumoniae type strain tested in parallel.ConclusionsBiofilm of the K. pneumoniae outbreak strain was tolerant to standard disinfection during duodenoscope reprocessing. This study establishes for the first time a direct link between biofilm formation, increased tolerance to disinfectants, reprocessing failure of duodenoscopes and nosocomial transmission of carbapenem-resistant K. pneumoniae.

Disinfecting Action of Gaseous Ozone on OXA-48-Producing Klebsiella pneumoniae Biofilm In Vitro.

Klebsiella pneumoniae is an emerging multidrug-resistant pathogen that can contaminate hospital surfaces in the form of a biofilm which is hard to remove with standard disinfectants. Because of biofilm resistance to conservative disinfectants, the application of new disinfection technologies is becoming more frequent. Ozone gas has antimicrobial activity but there is lack of data on its action against K. pneumoniae biofilm. The aim of this study was to investigate the effects and mechanisms of action of gaseous ozone on the OXA-48-procuding K. pneumoniae biofilm. A 24 h biofilm of K. pneumoniae formed on ceramic tiles was subsequently exposed to different concentrations of ozone during one and two hours to determine the optimal ozone concentration. Afterwards, the total bacteria count, total biomass and oxidative stress levels were monitored. A total of 25 ppm of gaseous ozone was determined to be optimal ozone concentration and caused reduction in total bacteria number in all strains of K. pneumoniae for 2.0 log10 CFU/cm2, followed by reduction in total biomass up to 88.15%. Reactive oxygen species levels significantly increased after the ozone treatment at 182% for the representative K. pneumoniae NCTC 13442 strain. Ozone gas in the concentration of 25 ppm caused significant biofilm reduction but did not completely eradicate the K. pneumoniae biofilm formed on ceramics. In conclusion, ozone gas has great potential to be used as an additional hygiene measure in joint combat against biofilm in hospital environments.

Gemini-Mediated Self-Disinfecting Surfaces to Address the Contact Transmission of Infectious Diseases.

According to both the Center for Disease Control and the World Health Organization, contact transmission is the primary transmission route of infectious diseases worldwide. Usually, this is mitigated by a schedule of repeated regular sanitization, yet surfaces are easily re-contaminated in the interim between cleanings. One solution to this problem is to generate self-disinfecting surfaces that can display sustained virucidal/antimicrobial properties against pathogens that settle upon them. Quaternary ammonium organosilicon compounds are ideal candidates to achieve this; cationic surfactants are safe and well-established surface disinfectants, while organosilanes are used broadly to form durable coatings with altered surface properties on many different materials. Despite their potential to circumvent the disadvantages of traditional disinfection methods, extant commercially available quaternary ammonium silanes do not display comparable efficacy to the standard surface disinfectants, nor have their respective coatings been demonstrated to meet the Environmental Protection Agency's guidelines for residual/extended efficacy. Inspired by the powerful surface activity of double-headed "gemini" surfactants, here, we present gemini-diquaternary silanes (GQs) with robust residual germicidal efficacy on various surfaces by incorporating a second cationic "head" to the structure of a conventional monoquaternary ammonium silane (MQ). Aqueous solutions of GQs were tested in suspension- and surface-antimicrobial assays against an array of pathogens, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). GQ performance was benchmarked against the common disinfectants, ethanol, hydrogen peroxide, hypochlorite, as well as MQ. Solutions of GQs were efficacious when used for immediate disinfection (>106-fold reduction in 15 s). Additionally, GQs were demonstrated to impart durable self-disinfecting properties to a variety of porous and nonporous surfaces, effective after repeated cycles of abrasion and repeated contaminations, and with superior coating ability and activity (>108 higher activity) than that of MQs. GQs as surface treatments show great promise to overcome the limitations of traditional disinfectants in preventing the spread of infectious diseases.

Using the electrohydraulic impact method to obtain manure fertilizers

Currently, animal husbandry and poultry farming waste, cattle and pig manure, bird droppings are prohibited to be exported to the fields and used as fertilizer without pretreatment. The standard disinfection process is reduced to composting, which takes 3-12 months. A promising direction of intensification of animal waste processing is the creation of a specially formed pulsed high-voltage electric discharge inside the liquid volume. Under the influence of which the microbial flora – bacteria and fungi - intensively dies. Specialists of the SPA “Spiral” have developed a pilot plant for manure treatment. The test results showed that coliform and Enterobacteria, including dysentery bacillus, were completely destroyed after processing a sample of cattle manure by the EGI method.

Characterizing the microbiota of instrumentation in ophthalmology clinics during and beyond the COVID-19 pandemic

PurposeIncreased ophthalmology-specific risk of novel coronavirus 2019 (SARS-CoV-2) transmission is well-established, increasing the fear of infection and causing associated decreased rates of procedures known to save vision. However, the potential transmission from exposure to clinic instrumentation is unknown, including which additional pathogens may be spreading in this context. This study seeks to fill this gap by characterizing the microbiota of instrumentation in ophthalmology clinics during the COVID-19 pandemic and identifying potential sources of pathogenic spread encountered by patients and healthcare workers.MethodsThirty-three samples were captured using standard cultures and media. Ten positive and negative controls were used to confirm proper technique. Descriptive statistics were calculated for all samples. Samples were collected from the retina (N = 17), glaucoma (N = 6), cornea (N = 6), and resident (N = 4) clinics with rigorous disinfection standards at a tertiary academic medical center. Standard media cultures and/or polymerase chain reaction (PCR) was performed for each sample.ResultsFrom 33 samples, more than half (17/33, 51.5%) yielded bacterial growth. Using two different molecular methods, three samples (3/33, 9%) tested positive for SARS-CoV-2 (cycle thresholds 36.48, 37.14, and 37.83). There was no significant difference in bacterial growth (95% confidence interval [95% CI]: − 0.644–0.358, p = 0.076) among different clinics (retina, glaucoma, cornea, resident). Staphylococcus (S.) epidermidis grew most frequently (12/35, 34%), followed by S. capitis (7/35, 20%), Micrococcus luteus (2/35, 5.7%), Corynebacterium tuberculostearicum (2/35, 5.7%), and Cutibacterium ([C.], Propionibacterium) acnes (2/35, 5.7%). C. acnes growth was more frequent with imaging device forehead rests (2/7, 28.6%) than other surfaces (0/26, 0%, 95% CI: 0.019–0.619, p = 0.040). No samples isolated fungus or adenovirus.ConclusionsMost samples across subspecialty clinic instrumentation grew bacteria, and several tested positive for SARS-CoV-2. Many isolated pathogens have been implicated in causing infections such as endophthalmitis, conjunctivitis, uveitis, and keratitis. The clinical implications of the ophthalmology microbiome for transmitting nosocomial infections warrant optimization of disinfection practices, strategies for mitigating spread, and additional study beyond the pandemic. Supplementary InformationThe online version contains supplementary material available at 10.1007/s00417-022-05639-0.