Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Among Residents and Employees in a Veterans Affairs Community Living Center: A 42-Month Prospective Cohort Study.

Background: Understanding routes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission in long-term care facilities is essential for the development of effective control measures. Methods: Between March 1, 2020, and August 31, 2023, we identified coronavirus disease 2019 (COVID-19) cases among residents and employees in a Veterans Affairs community living center that conducted routine screening for asymptomatic COVID-19. Contact tracing was conducted to identify suspected transmission events, and whole genome sequencing was performed to determine the relatedness of SARS-CoV-2 samples. Results: During the 42-month study period, 269 cases of COVID-19 were diagnosed, including 199 employees and 70 residents. A total of 48 (24.1%) employees and 30 (42.9%) residents were asymptomatic. Sequencing analysis provided support for multiple events in which employees transmitted SARS-CoV-2 to co-workers and residents. There was 1 episode of likely transmission of SARS-CoV-2 from one resident to another resident, but no documented transmissions from residents to employees. Conclusions: Transmission of SARS-CoV-2 in the community living center predominantly involved transmission from employees to co-workers and residents. There is a need for improved measures to prevent transmission of SARS-CoV-2 by healthcare personnel.

Evaluation of an Automated Wall-mounted Far Ultraviolet-C Light Technology for Continuous or Intermittent Decontamination of Candida auris on Surfaces.

Background: Technologies that provides safe and effective decontamination of surfaces and equipment between episodes of manual cleaning could be an important advance in efforts to prevent transmission of the emerging fungal pathogen Candida auris. Methods: We tested the efficacy of a novel wall-mounted far ultraviolet-C (UV-C) light technology that delivers far UV-C, when people are not detected within the field of illumination, against C. auris isolates from clades I, II, III, and IV using a quantitative disk carrier test method. In an equipment room, we examined the efficacy of the technology in reducing an isolate of C. auris from clade IV inoculated on multiple sites on portable devices. Results: The far UV-C technology reduced isolates from all 4 clades of C. auris by >3 log10 colony-forming units (CFU) aſter an 8-hour exposure on steel disks. For the clade IV isolate, similar reductions were achieved on glass and plastic carriers. In the equipment room, the technology reduced C. auris inoculated on multiple sites on portable equipment by >2 log10 CFU in 4 hours. Conclusions: The far UV-C technology could be useful for decontamination of surfaces and equipment between episodes of manual cleaning. Additional studies are needed to evaluate the use of the technology in clinical settings.

Bacteria Invade the Brain Following Sterile Intracortical Microelectrode Implantation.

Brain-machine interface performance is largely affected by the neuroinflammatory responses resulting in large part from blood-brain barrier (BBB) damage following intracortical microelectrode implantation. Recent findings strongly suggest that certain gut bacterial constituents penetrate the BBB and are resident in various brain regions of rodents and humans, both in health and disease. Therefore, we hypothesized that damage to the BBB caused by microelectrode implantation could amplify dysregulation of the microbiome-gut-brain axis. Here, we report that bacteria, including those commonly found in the gut, enter the brain following intracortical microelectrode implantation in mice implanted with single-shank silicon microelectrodes. Systemic antibiotic treatment of mice implanted with microelectrodes to suppress bacteria resulted in differential expression of bacteria in the brain tissue and a reduced acute inflammatory response compared to untreated controls, correlating with temporary improvements in microelectrode recording performance. Long-term antibiotic treatment resulted in worsening microelectrode recording performance and dysregulation of neurodegenerative pathways. Fecal microbiome composition was similar between implanted mice and an implanted human, suggesting translational findings. However, a significant portion of invading bacteria was not resident in the brain or gut. Together, the current study established a paradigm-shifting mechanism that may contribute to chronic intracortical microelectrode recording performance and affect overall brain health following intracortical microelectrode implantation.

Efficacy of 23 commonly used liquid disinfectants against Candida auris isolates from the 4 major clades.

We tested the effectiveness of 23 disinfectants used in healthcare facilities against isolates from the 4 major clades of Candida auris. Sporicidal disinfectants were consistently effective, whereas quaternary-ammonium disinfectants had limited activity. Quaternary-ammonium-alcohol and hydrogen-peroxide-based disinfectants varied in effectiveness against C. auris.

Efficacy of a far-ultraviolet-C light technology for continuous decontamination of air and surfaces.

A wall-mounted, far-ultraviolet-C light technology reduced aerosolized bacteriophage MS2 by >3 log10 plaque-forming units within 30 minutes. Vegetative bacterial pathogens on steel disk carriers in the center of the room were reduced by >3 log10 after 45 minutes of exposure, but Candida auris and Clostridioides difficile spores were not.

Pulsed dosing and extended daily dosing of oral vancomycin do not facilitate clearance of Clostridioides difficile colonization in mice.

Vancomycin taper and pulse regimens are commonly used to treat recurrent Clostridioides difficile infections, but the mechanism by which these regimens might reduce recurrences is unclear. Here, we used a mouse model to test the hypothesis that pulse dosing of vancomycin after a 10-day treatment course enhances clearance of C. difficile from the intestinal tract. Mice with C. difficile colonization received 10 days of once-daily oral vancomycin followed by 20 days of treatment with saline (controls), daily vancomycin, or pulse dosing of vancomycin every 2 or 3 days. Stool samples were collected to measure the concentration of C. difficile during and after treatment, vancomycin concentrations, and growth of vegetative C. difficile during every 3 days dosing. Pulse dosing of vancomycin was not effective in maintaining suppression of C. difficile (P > 0.05 in comparison to saline controls); growth of vegetative C. difficile occurred between pulse doses when vancomycin decreased to undetectable levels. Daily dosing of vancomycin suppressed C. difficile during treatment, but recurrent colonization occurred after treatment in more than 75% of mice, and by post-treatment day 14, there was no significant difference among the control, pulse dosing, and daily dosing groups (P > 0.05). These findings demonstrate that pulse dosing of vancomycin every 2 or 3 days does not facilitate the clearance of C. difficile spores in mice. Studies are needed to examine the impact of vancomycin taper and pulsed regimens in patients.

Inactivation and/or physical removal of Candida auris from floors by detergent cleaner, disinfectants, microfiber, and ultraviolet C light (UV-C).

Contaminated surfaces may be a source of transmission for the globally emerging pathogen, Candida auris. Because floors may be a source of C. auris contamination on hands, strategies for inactivating or removing C. auris from floors were investigated. A sporicidal disinfectant and UV-C were most effective in inactivating C. auris on floors.

Evaluation of a mobile disinfection cabinet using ultraviolet-C light and aerosolized hydrogen peroxide for disinfection of medical equipment.

In laboratory testing, a mobile enclosed disinfection cabinet using ultraviolet-C light and aerosolized hydrogen peroxide was effective for disinfection of hard and soft surfaces. The addition of aerosolized hydrogen peroxide to ultraviolet-C light resulted in improved disinfection of soft surfaces and Clostridioides difficile spores.

Carbon Dioxide Monitoring Demonstrates Variations in the Quality of Ventilation on Public Transportation Buses and University Student Shuttle Vans and Identifies Effective Interventions.

Background: There is a risk for transmission of severe acute respiratory syndrome 2 (SARS-CoV-2) and other respiratory viruses in motor vehicles, particularly if ventilation is inadequate. Methods: We used carbon dioxide monitoring to examine the quality of ventilation in several public transportation buses and in university student shuttle vans in the Cleveland metro area during peak and non-peak travel times. Carbon dioxide levels above 800 parts per million (ppm) were considered an indicator of suboptimal ventilation for the number of people present. In the shuttle vans, we evaluated the impact of an intervention to improve ventilation. Results: In large articulated buses with 2 ventilation systems, carbon dioxide concentrations never exceeded 800 ppm, whereas in standard buses with 1 ventilation system concentrations rose above 800 ppm during peak travel times and on some trips during non-peak travel times. In shuttle vans, the ventilation system was not turned on during routine operation, and carbon dioxide levels rose above 800 ppm on all trips during peak and non-peak travel times. In the shuttle vans, an intervention involving operation of the existing ventilation system resulted in a significant reduction in carbon dioxide levels (mean concentration, 1,042 no intervention versus 785 with intervention; P < 0.001). Conclusions: Our findings demonstrate substantial variability in the quality of ventilation in public transportation buses and university shuttle vans. There is a need for efforts to assess and optimize ventilation in motor vehicles used for public transportation to reduce the risk for aerosol-mediated transmission of respiratory viruses. Carbon dioxide monitoring may provide a useful tool to assess and improve ventilation.

Empowering patients to prevent healthcare-associated infections.

In recent years there has been increasing interest in the empowerment of patients to serve as partners in efforts to prevent healthcare-associated infections. However, patients often have limited awareness of the risk for acquisition and dissemination of healthcare-associated pathogens and have received limited information on how they might participate in infection prevention efforts. This review highlights some of the areas where patient empowerment initiatives in infection control and antimicrobial stewardship may be useful and reviews available evidence that such initiatives can be beneficial. Although patients are the primary focus of these initiatives, inclusion of family members should be considered in many situations because they often play a major role in healthcare decision-making.

Update on potential interventions to reduce the risk for transmission of health care-associated pathogens from floors and sinks.

Health care facility floors and sink drains and other wastewater drainage sites are universally contaminated with potential pathogens and there are plausible mechanisms by which organisms can be disseminated from these sites. However, floors and sink drains are not addressed as potential sources of pathogen transmission in most health care facilities. One factor that has hindered progress in addressing floors and sinks has been the lack of practical and effective measures to reduce the risk for dissemination of organisms from these sites. This article provides an update on some of the potential interventions being used to reduce the risk for transmission of health care-associated pathogens from floors and sinks. Practical approaches to address these sites of contamination are emphasized.

High technology and low technology measures to reduce risk of SARS-CoV-2 transmission.

During the coronavirus disease 2019 (COVID-19) pandemic, a variety of low technology and high technology measures have been proposed to reduce the risk for transmission. Identifying those measures likely to be useful in reducing viral transmission without undue expense or potential for adverse effects has been a challenge for infection control programs. The challenge has been compounded by the lack of tools that can be used to assess the risk for viral transmission in different settings. This review discusses practical tools that can be used to assess ventilation and airflow and evaluates some of the low technology and high technology measures that have been proposed as control measures for COVID-19. Some typical questions posed to infection control programs during the pandemic are presented to illustrate real-world application of the concepts being discussed.

Disinfection and sterilization: New technologies.

BACKGROUND: Adherence to professional guidelines and/or manufacturer's instructions for use regarding proper disinfection and sterilization of medical devices is crucial to preventing cross transmission of pathogens between patients. Emerging pathogens (e.g., Candida auris) and complex medical devices provide new challenges. METHODS: A search for published English articles on new disinfection and sterilization technologies was conducted by Google, Google scholar and PubMed. RESULTS: Several new disinfection methods or products (e.g., electrostatic spraying, new sporicides, colorized disinfectants, "no touch" room decontamination, continuous room decontamination) and sterilization technologies (e.g., new sterilization technology for endoscopes) were identified. CONCLUSIONS: These technologies should reduce patient risk.

Continuous surface and air decontamination technologies: Current concepts and controversies.

Effective and safe continuous surface and air decontamination technologies could be a useful adjunct to routine cleaning and disinfection in health care settings. Continuously active quaternary ammonium disinfectants that provide residual antimicrobial activity on undisturbed surfaces for up to 24.ßhours have been shown to reduce the recovery of clinically important pathogens in some but not all real-world studies. Although quaternary ammonium-based supplemental coatings have been reported to provide prolonged residual efficacy in patient care settings, there is concern that some of these products may be removed by routine cleaning and disinfection. To address this concern, the Environmental Protection Agency has recently issued updated guidance requiring demonstration of efficacy after multiple abrasion and chemical exposures for registration of supplemental residual antimicrobial coatings. Far-ultraviolet-C and direct irradiation below exposure limits are promising technologies for continuous air and surface decontamination in occupied spaces, but additional studies are needed to evaluate their long-term safety and efficacy. Given the increasing use of electronic air cleaning technologies in community and health care settings, there is a need for studies to assess real-world efficacy and safety.