Room Disinfection Research Articles

Operating room sterilization and disinfection methods

Operating room sterilization and disinfection methods

Surface Disinfection Systems with UV-C Lamps – Verification Measurements and Design Procedure Proposal

ABSTRACT Ultraviolet radiation in the UV-C range is widely applied to disinfect surfaces, air, and water. UV-C (germicidal) lamps are commonly used, and their application is reliable, scientifically proven, and efficient to inactivate various types of bacteria, viruses, and fungal spores, including the SARS-CoV-2 virus. This research aims to develop a UV-C irradiance design procedure for germicidal devices disinfecting surfaces in rooms. This procedure considers the required values of UV-C radiation doses that disinfect rooms efficiently. For this purpose, it has been proposed to apply the DIALux evo software to design the appropriate UV-C irradiance on disinfected room surfaces using different germicidal devices. The measurements verified the accuracy of the simulation performed in the DIALux evo software, which also considered the reflection of the ultraviolet radiation from the principal planes of the room. Two rooms with different dimensions were selected to verify the computational accuracy of the developed design procedure for the disinfection system. Ultraviolet lamps were placed in the rooms, and irradiance measurements were taken at the selected measuring points. The results of the irradiance measurements were compared. The comparative analysis of the disinfection device proved that it was possible to adapt the DIALux evo software to make the calculations for designing room disinfection systems. The research made it possible to determine a suitable design procedure for surface disinfection systems, which prevents errors in proper surface disinfection after implementing UV-C lamps in the room.

Ozone processing of milk and milk products: a review of applications, quality effect and implementation challenges

Abstract The impact on the natural characteristics of dairy products during thermal processing warrants the investigation of non-thermal techniques. Ozone has proved to be an effective and sustainable processing technology for the dairy processing sector. This review delves into the effect of ozone processing on the microbiological, physiochemical, nutri-functional, and sensory quality of milk and milk products. Alongside this, the other ozone applications in the dairy processing sector (storage room disinfection, wastewater treatment, benefits in Clean-in-Place (CIP) system, toxin reduction) have been discussed. Current regulatory and industrial status, and safety requirements in the facility have also been highlighted. Overall, ozone treatment has lower microbial inactivation efficiency in milk and milk products than thermal treatment. Further, safety precautions are needed in the processing areas due to its potential health hazard concerns.

Performance of an Autonomous Sanitary Sterilisation Ultraviolet Machine (ASSUM) on terminal disinfection of surgical theaters and rooms of an intensive-intermediate care unit

Ultraviolet- C (UV-C) light is effective for reducing environmental bioburden in hospitals, and the use of robots to deliver it may be advantageous. To evaluate the feasibility and clinical efficacy of an autonomous programmable UV-C robot in surgical and intensive care unit (ICU) rooms of a tertiary hospital. During ten consecutive months, the device was used in six theatres where cardiac, colorectal and orthopaedic surgeries were performed, and in the rooms previously occupied by patients subjected to contact precautions of a 14-bed ICU. Surgical site infection (SSI) rates of procedures performed in the UV-cleaned theatres were compared with those of the previous year. Incidence in clinical samples of ICU-acquired multiple-drug resistant (MDR) microorganisms was compared with that of the same period of the previous year. An UV-C exposure study done by semi-quantitative dosimeters and a survey of the bioburden on surfaces were carried out. SSI rates in the pre- and post-intervention periods were 8.67% (80/922) and 7.5% (61/813), respectively (p=0.37). Incidence of target microorganisms in clinical samples remained unchanged (38.4 vs. 39.4 per 10,000 patient-days, p=0.94). All the dosimeters exposed to ≤1 meter received ≥500 mJ/cm2. The bacterial load on surfaces decreased after the intervention, particularly in ICU rooms (from 4.57±7.4 CFU to 0.27±0.8 CFU, p<0.0001). Deployment of an UV-C robot in surgical and ICU rooms is feasible, ensures adequate delivery of germicidal UV-C light and reduces the environmental bacterial burden. Rates of surgical site infections or acquisition of MDR in clinical samples of critically-ill patients remained unchanged.

"No Touch" Room Disinfection Technology.

"No Touch" Room Disinfection Technology.

Estimation of the UV susceptibility of aerosolized SARS-CoV-2 to 254 nm irradiation using CFD-based room disinfection simulations

The recent COVID-19 pandemic has raised interest in efficient air disinfection solutions. The application of germicidal ultraviolet (GUV) irradiation is an excellent contender to prevent airborne transmission of COVID-19, as well as other existing and future infectious airborne diseases. While GUV has already been proven effective in inactivating SARS-CoV-2, quantitative data on UV susceptibility and dose requirements, needed to predict and optimize the performance of GUV solutions, is still limited. In this study, the UV susceptibility of aerosolized SARS-CoV-2 to 254 nm ultraviolet (UV) irradiation is investigated. This is done by employing 3D computational fluid dynamics based simulations of SARS-CoV-2 inactivation in a test chamber equipped with an upper-room UV-C luminaire and comparing the results to previously published measurements performed in the same test chamber. The UV susceptibility found in this study is (0.6 ± 0.2) m2/J, which is equivalent to a D90 dose between 3 and 6 J/m2. These values are in the same range as previous estimations based on other corona viruses and inactivation data reported in literature.

Environmental Contamination in Relation to cDHP in Candida auris Patient Rooms as Measured by ATPase

Background: Candida auris (CA) is an urgent threat per Centers for Disease Control and Prevention with rapidly increasing cases across the US. Patient rooms recontaminate with CA within hours after daily cleaning due to skin shedding, persistence on environmental surfaces and resistance to commonly used disinfectants. Continuous dry hydrogen peroxide (cDHP) is a novel environmental technology augmenting daily room disinfection. cDHP reduces CA organism counts based on environmental cultures. Adenosine triphosphatase (ATPase) testing offers rapid results to monitor surface cleanliness. ATPase Testing Protocol: Upon identification of CA, cDHP was activated in the patient’s room. ATPase surface testing was performed in rooms of CA infected inpatients and nearby control rooms of inpatients without CA and thus no cDHP. Group A surfaces near the patient were nurse call handheld devices and/or bed rail. Group B surfaces were horizontal counter and/or computer keyboard, located &gt;3 feet away from the patient. ATPase testing was to occur within one hour of daily room disinfection for CA patient Day0 (day of cDHP activation), Day1, Day7 and Day14 and controls. Daily room disinfection using quaternary disinfectants was replaced with EPA Class P chemicals upon CA identification. Nursing spot disinfects with Class P ready to use disinfectant wipes in all rooms. Results: Testing occurred among 13 CA and 22 control patients in 5 hospitals. In Table 1, pass rates are displayed by cumulative (Day0+1+7+14) test days for surfaces and patient room groups. Analysis applied Pearson’s Chi-squared test with Yates’ continuity correction. Conclusions: Surfaces further from the patient in rooms of CA patients exposed to cDHP had higher ATPase pass rates than controls. Surfaces close to the patient have a high ATPase failure rate, regardless of CA or cDHP. Strategies are needed to ensure disinfection occurs on high touch surfaces near patients. cDHP may have value in supplementing room disinfection. Contributing failure factors include surfaces missed for disinfection, delays in timely testing and known limitations with ATPase methods.

A Quality Improvement Project to Increase Infection Control Compliance Among Endoscopy Staff at a Large Urban Medical Center

Although nurses and other healthcare professionals play a key role in preventing hospital-associated infections, studies show that infection control compliance rates have remained low. The purpose of this quality improvement project was to increase infection control compliance of hand hygiene and procedure room disinfection among endoscopy staff at a large urban medical center in Cincinnati, Ohio. This quality improvement project provided an education session on current evidence-based infection control guidelines to 20 participants, including registered nurses and technicians within the endoscopy department. Direct observational audits were conducted 4 weeks before and 4 weeks after the education session, measuring compliance with hand sanitizer, soap and water, and procedure room disinfection, over a period of 150 days. The project goals were met, as hand sanitizer compliance improved by 12%–83%; overall soap and water compliance improved by 20%–75%; and endoscopy procedure room disinfection compliance improved by 14%–92%.

Rapid Environmental Contamination With Candida auris and Multidrug-Resistant Bacterial Pathogens Near Colonized Patients.

Environmental contamination is suspected to play an important role in Candida auris transmission. Understanding speed and risks of contamination after room disinfection could inform environmental cleaning recommendations. We conducted a prospective multicenter study of environmental contamination associated with C. auris colonization at 6 ventilator-capable skilled nursing facilities and 1 acute care hospital in Illinois and California. Known C. auris carriers were sampled at 5 body sites followed by sampling of nearby room surfaces before disinfection and at 0, 4, 8, and 12 hours after disinfection. Samples were cultured for C. auris and bacterial multidrug-resistant organisms (MDROs). Odds of surface contamination after disinfection were analyzed using multilevel generalized estimating equations. Among 41 known C. auris carriers, colonization was detected most frequently on palms/fingertips (76%) and nares (71%). C. auris contamination was detected on 32.2% (66/205) of room surfaces before disinfection and 20.5% (39/190) of room surfaces by 4 hours after disinfection. A higher number of C. auris-colonized body sites was associated with higher odds of environmental contamination at every time point following disinfection, adjusting for facility of residence. In the rooms of 38 (93%) C. auris carriers co-colonized with a bacterial MDRO, 2%-24% of surfaces were additionally contaminated with the same MDRO by 4 hours after disinfection. C. auris can contaminate the healthcare environment rapidly after disinfection, highlighting the challenges associated with environmental disinfection. Future research should investigate long-acting disinfectants, antimicrobial surfaces, and more effective patient skin antisepsis to reduce the environmental reservoir of C. auris and bacterial MDROs in healthcare settings.

Inactivation of human coronaviruses using an automated room disinfection device

The emergence of more virulent and epidemic strains of viruses, especially in the context of COVID-19, makes it more important than ever to improve methods of decontamination. The objective of this study was to evaluate the potential of on-demand production of chlorine species to inactivate human coronaviruses. The commercial prototype disinfection unit was provided by Unipolar Water Technologies. The Unipolar device generates active chlorine species using an electrochemical reaction and dispenses the disinfectant vapour onto surfaces with an aspirator. The minimum effective concentration and exposure time of disinfectant were evaluated on human hepatoma (Huh7) cells using 50% tissue culture infectious dose (TCID50) assay and human coronavirus 229E (HCoV-229E), a surrogate for pathogenic human coronaviruses. We showed that chlorine species generated in the Unipolar device inactivate HCoV-229E on glass surfaces at ≥ 400 parts per million active chlorine concentration with a 5 min exposure time. Here, inactivation refers to the inability of the virus to infect the Huh7 cells. Importantly, no toxic effect was observed on Huh7 cells for any of the active chlorine concentrations and contact times tested.

Countermeasures of Hotel Industry for Tourism Crisis Management Under the Influence of Epidemic Situation

On a global scale, the epidemic has had a great impact on tourism, and the hotel industry, as a key component of tourism, has also been seriously affected. The purpose of this paper is to study the impact of the epidemic on the hotel industry and put forward coping strategies to help the hotel industry effectively cope with the tourism crisis. First of all, the epidemic has led to a sharp decline in tourism, a sharp drop in the occupancy rate of the hotel industry and a sharp drop in income. In order to meet this challenge, the hotel industry needs to adopt the strategy of diversified income sources and reduce its dependence on the traditional tourism market. Secondly, the hotel industry should formulate more flexible cancellation policies to meet customer needs. Third, the hotel industry should strengthen cleaning and hygiene measures to ensure the health and safety of customers when they check in. This includes regular disinfection of guest rooms and public areas, provision of hand sanitizer, masks and other sanitary products. A transparent cleaning policy can improve the trust of customers. In addition, digital technology plays a key role in crisis management. Finally, staff training is the key link to deal with the crisis. This paper studies the coping strategies of crisis management in the hotel industry under the influence of epidemic situation, which is helpful for the hotel industry to tide over the crisis, maintain business sustainability and prepare for future uncertainty.

Description and results of a new method for assessing real-life performance of a UV-C disinfection robot

Due to the disadvantages of manual disinfection of patient rooms, mobile disinfection robots using ultraviolet C (UV-C) radiation are increasingly being used. Assessing their in situ effectiveness remains challenging. This study describes a new method to prove adequate in situ disinfection (≥5-log reduction in bacterial load), and uses this method to assess the efficacy of a mobile disinfection robot using UV-C radiation. Agar plates serving as proxies for smooth surfaces in patient rooms were inoculated with bacterial suspension and placed on various surfaces in a patient room. After irradiation by an automated mobile UV-C robot, reduction in colony growth was determined by comparing the irradiated plates to a reference series of non-irradiated plates, enabling the evaluation of whether an adequate reduction in colony-forming units (CFU's) of ≥5-log was reached on these irradiated surfaces. The new technique described here proved a successful method for demonstrating an in situ ≥5-log reduction in CFU's for five different bacterial pathogens. Of the 32 plates placed on UV-accessible surfaces, 31 showed an adequate reduction in CFU's of ≥5-log. One plate could not be assessed. Inoculated agar plates placed in patient rooms before irradiation and subsequently compared to a reference series can be used to assess in situ efficacy of mobile disinfection robots using UV-C radiation. Our findings support the idea that UV-C robots, used adjunctively to conventional manual washing and disinfection, may achieve adequate bacterial load reduction on UV-accessible smooth surfaces in patient rooms for a selected subset of pathogens.

..úNo touch..Ñ methods for health care room disinfection: Focus on clinical trials

Hospital patient room surfaces are frequently contaminated with multidrug-resistant organisms. Since studies have demonstrated that inadequate terminal room disinfection commonly occurs, ..úno touch..Ñ methods of terminal room disinfection have been developed such as ultraviolet light (UV) devices and hydrogen peroxide (HP) systems. This paper reviews published clinical trials of ..úno touch..Ñ methods and ..úself-disinfecting..Ñ surfaces. Multiple papers were identified including clinical trials of UV room disinfection devices (N.ß=.ß20), HP room disinfection systems (N.ß=.ß8), handheld UV devices (N.ß=.ß1), and copper-impregnated or coated surfaces (N.ß=.ß5). Most but not all clinical trials of UV devices and HP systems for terminal disinfection demonstrated a reduction of colonization/infection in patients subsequently housed in the room. Copper-coated surfaces were the only ..úself-disinfecting..Ñ technology evaluated by clinical trials. Results of these clinical trials were mixed. Almost all clinical trials reviewed used a ..úweak..Ñ design (eg, before-after) and failed to assess potential confounders (eg, compliance with hand hygiene and environmental cleaning). The evidence is strong enough to recommend the use of a ..úno-touch..Ñ method as an adjunct for outbreak control, mitigation strategy for high-consequence pathogens (eg, Candida auris or Ebola), or when there are an excessive endemic rates of multidrug-resistant organisms.

Biofilms on medical instruments and surfaces: Do they interfere with instrument reprocessing and surface disinfection

Biofilms are surface-attached communities of bacteria embedded in an extracellular matrix. This matrix shields the resident cells from desiccation, chemical perturbation, invasion by other bacteria, and confers reduced susceptibility to antibiotics and disinfectants. There is growing evidence that biofilms on medical instruments (especially endoscopes) and environmental surfaces interfere with cleaning and disinfection. The English literature on the impact of biofilms in medicine was reviewed with a focus on the impact of biofilms on reusable semicritical medical instruments and hospital environmental surfaces. Biofilms are frequently present on hospital environmental surfaces and reusable medical equipment. Important health care...associated pathogens that readily form biofilms on environmental surfaces include Staphylococcus aureus, Pseudomonas aeruginosa, and Candida auris. Evidence has demonstrated that biofilms interfere with cleaning and disinfection. New technologies such as ..úself-disinfecting..Ñ surfaces or continuous room disinfection systems may reduce or disrupt biofilm formation and are under study to reduce the impact of the contaminated surface environment on health care...associated infections. Future research is urgently needed to develop methods to reduce or eliminate biofilms from forming on implantable medical devices, reusable medical equipment, and hospital surfaces.

Limited reduction in Clostridioides difficile and Methicillin-Resistant Staphylococcus aureus with the use of an aerosolized hydrogen peroxide disinfection system in tertiary health care facilities in Alberta, Canada

Nonmanual room disinfection systems may reduce the transmission of infections. A variety of systems have emerged; however, a paucity of evidence exists to make an evidence-informed decision for the implementation of a specific system. Alberta Health Services assessed one of these systems. A quasi-experimental prepost design assessed an aerosolized hydrogen peroxide disinfection system on 6 units at 3 acute care facilities in Alberta. To assess clinical effectiveness an interrupted time-series analysis with Poisson distribution compared changes in hospital-acquired Clostridioides difficile infection (HA-CDI) and hospital-acquired Methicillin-resistant Staphylococcus aureus (HA-MRSA) between preintervention, intervention, and postintervention periods. To assess operational feasibility cleaning turnaround time, time to operate, and utilization were considered. A participatory research framework was used to understand the benefits and challenges of operationalization. Incidence rate ratio (IRR) of HA-CDI decreased by 25.7% on FMC-A and 6.9% on RAH-B. Following withdrawal, the IRR of HA-CDI continued to decrease. IRR of HA-MRSA decreased by 25.0% on RAH-B. Following withdrawal, the IRR of HA-MRSA continued to decrease. None of the results were statistically significant. The average time to operate was 3.2hours. Utilization was between 1.7% and 25.6%. Most staff reported benefits and challenges. None of the changes observed in HA-CDI and HA-MRSA after the introduction of the aerosolized hydrogen peroxide system were statistically significant. While most respondents reported multiple benefits and challenges in using the system, the core challenge was delays in inpatient admissions due to the time operate the system. Successful implementation of a nonmanual room disinfection system as an addition to standard cleaning and disinfection requires significant investment and must consider a variety of factors.

Clinical management and infection control protocols during the COVID-19 pandemic: An online survey.

SARS-CoV-2 (COVID-19) is considered a highly infectious and life threatening disease. The present paper aims to evaluate various aspects of preventive measures and clinical management of the scheduled visits for orthodontic patients to the dental clinics during the outbreak of COVID-19, and to assess how orthodontists dealt with this challenge. Orthodontists in private and public clinics were invited to fill a questionnaire that addressed infection control protocols and concerns about clinical management of patients in the clinics during the pandemic. Frequncies and percentages of the responses were obtained and compared using Chi-square tests. About 77% of those working in private clinics, and 63% of those working in private and governmental clinics performed room disinfection following each patient. In case of patients needing urgent management and have active infection, 56% of the participants provided care under high infection control measures; on the contrary, 64% provided symptomatic intervention including orthodontic wax, analgesics and sometimes mouthwash. The COVID-19 pandemic has had a negative impact on the orthodontic treatments. All pre-cautionary measures have to be made available in the clinic in order to minimize the spread of viral infection with continuous dental health care training.

Operating room disinfection: operator-driven ultraviolet ‘C’ vs. chemical treatment

In operating room (OR) surfaces, Nosocomial pathogens can persist on inanimate surfaces for long intervals and are highly resistant to traditional surface cleaning. This study compares traditional chemical operating room terminal disinfection to a unique operator-driven device that emits germicidal UV light at short distance onto vertical and horizontal surfaces. A randomized crossover analogous protocol assigned 40 end-of-day operating rooms into either group A (chemical then UVC treatments) or group B (UVC then chemical treatments). Initial Staphylococcal cultures were obtained prior to disinfection treatment, after the first treatment, and after the second treatment at 16 most commonly contaminated sites to represent overall room contamination. Success was defined as no growth and failure as 1 or more colony forming units. Thoroughness of chemical treatment vs UVC treatment was compared and used to determine if the second treatment was additive to the first treatment within each group. The operator driven UVC device outperformed chemical treatment in reducing the number of contaminated sites in the OR by more than half (P<0.001). Operator-driven UVC reduced contaminated sites after chemical treatment by nearly half (P<0.001). In contrast, chemical treatment after operator-driven UVC did not significantly reduce the number of contaminated sites. The mean employee time of disinfection for chemical treatment was 49 minutes and for the operator-driven UVC emitter 7.9 minutes (P<0.001). This study demonstrates that addition of an operator-driven UVC emitter to OR rooms between cases could be helpful in overall decreasing the number of contaminated sites.

Tolerance of clinical vancomycin-resistant Enterococcus faecium isolates against UV-C light from a mobile source

BackgroundAdmission to a room previously occupied by patients carrying environmentally robust pathogens implies an increased risk of acquiring those pathogens. Therefore, ‘No-touch’ automated room disinfection systems, including devices based on UV-C irradiation, are discussed to improve terminal cleaning. It is still unclear if clinical isolates of relevant pathogens behave differently under UV-C irradiation compared to laboratory strains used in the approval process of disinfection procedures. In this study we analysed the susceptibility of well characterized clonally divergent vancomycin-resistant enterococci (VRE) strains, including a linezolid-resistant isolate, against UV-C radiation.MethodsSusceptibility against UV-C of ten clonally divergent clinical isolates of VRE was determined in comparison to the commonly used test organism Enterococcus hirae ATCC 10541. Ceramic tiles contaminated with 105 to 106 colony forming units/25 cm² of the different enterococci were positioned at a distance of 1.0 and 1.5 m and irradiated for 20 s, resulting in a UV-C dose of 50 and 22 mJ/cm², respectively. Reduction factors were calculated after quantitative culture of the bacteria recovered from treated and untreated surfaces.ResultsSusceptibility to UV-C varied considerably among the strains studied, with the mean value of the most robust strain being up to a power of ten lower compared to the most sensitive strain at both UV-C doses. The two most tolerant strains belonged to MLST sequence types ST80 and ST1283. The susceptibility of the laboratory strain E. hirae ATCC 10541 ranged between the most sensitive and most tolerant isolates for both irradiation doses. However, for UV-C dose of 22 mJ/cm², the reduction of the most tolerant isolate of ST1283 was statistically significantly lower compared to E. hirae ATCC 10541. The most susceptible strains belonged to the MLST sequence types ST117 and ST203.ConclusionsThese results indicate that UV-C doses reported in the literature are sufficient for the reduction of commonly used reference strains of enterococci but could be insufficient for the reduction of tolerant patient VRE-isolates in a hospital setting. Therefore, for future studies, the most tolerant clinical isolates should be used to validate automated UV-C devices or longer exposure times should be expected to ensure efficacy in the real world.

#3351 TRIAL OF ISOLATED HAEMODIALYSIS WITH PATIENT-ENTRY TENT AND HYPOCHLORITE MIST

Abstract Background and Aims The global spread of COVID-19 has posed a serious threat to patients receiving renal replacement therapy and to the staff who treat them. Every time they treat a patient or operate a machine, they have to wear personal protective equipment (PPE). In order to reduce the burden on our staff, we have introduced two pieces of equipment. One is a hypochlorous acid mist for room and surface disinfection using CLFine®. The other is an AIR ZIPPER® patient isolation tent in the existing isolation room. Both products were manufactured by Nipro Corporation of Osaka, Japan. However, there was no evidence to support the use of hypochlorous acid in an ultrasonic humidifier. Therefore, Nipro Corporation conducted a “28-day repeated inhalation toxicity study” on rats with a third party organisation and confirmed the results as toxicologically safe. According to the Occupational Safety and Health Act, also in the school environmental health, the concentration of chlorine in the air is 0.5 ppm or less (8 hours/day, 5 days/week or less). CL Fine® has shown an antiviral effect within these regulations. The size of the AIR ZIPPER® is about a fifth of the standard 10m3 size, down to about 2m3. Powerful, high-efficiency particulate air filter pumps have been fitted to replace the air in the tent in less than 5 minutes at low flow rates (0.4 m3/min airflow), enabling it to operate below the negative pressure standard of 2.5 Pascal. In addition, the AIR ZIPPER® is equipped with air intake valves that open and close in a single direction towards the inside of the tent. Prior to the introduction of the AIR ZIPPER®, staff had to wear PPE with an N95 mask when operating the machine, puncturing and returning blood to the patient. Method Patients with a fever or who have been in contact with COVID-19 patients and infected patients were asked to enter the AIRZIPPER®. The haemodialysis machine is placed outside. The zipper of the AIRZIPPER® could not be closed until the puncture procedure had been completed. To reduce the spread of viruses outside the tent, the high air volume (air flow rate 0.9 m3/min) allows a one-way air flow from the outside to the inside. Following the puncture, the tent zipper was sealed and the air pressure was adjusted to reach the recommended negative pressure of 2.5 Pa and above within 1 minute. Furthermore, the hypochlorous acid mist with CLFine® has the ability to disinfect viruses from the outside of the AIR ZIPPER®. Therefore, after the 30 minutes with the zip closed in the isolation room, the outside of the AIR ZIPPER® was operated as a safe zone. Results On 13 January 2022, two pieces of equipment arrived at the Toshin Clinic and all patients carrying COVID-19 who subsequently developed the disease were isolated and haemodialysed. Quarantine dialysis was performed in 156 patients, including those who had close contact with a COVID-19 patient or who had fever. A total of 96 isolation haemodialysis sessions using AIR ZIPPER® and CL Fine® were performed on 22 COVID-19 patients (male/female: 19/3, age: 69.8 ± 14.2 years, HD duration: 5.38 ± 3.8 years) with SARS-CoV-2 infection in our clinic. Fortunately, there was no transmission to staff or other patients, and no patients died. Conclusion These infection control measures helped to reduce staff workload and prevent infections. In conclusion, the present method should be equipped by all haemodialysis providers to deal with Covid 19 infections as well as with new infections in the future.

COVID-19 outbreak in an acute psychiatric unit—Unique challenges and creative solutions

Background: We describe the management of a major COVID-19 outbreak in January 2022 during the SARS-CoV-2 omicron-variant winter surge involving the only inpatient psychiatric facility of Santa Clara County, California, which serves a population of 1.9 million. Methods: On January 14, 2022, infection prevention staff were notified of a symptomatic COVID-19 case in our locked inpatient psychiatric unit who had been admitted since October 2021. The index patient had no visitors or transfers outside the unit. The patients in this unit were noncompliant with masking and mingled with each other during meals. Initial testing identified 23 positive cases among 47 patients and 12 staff cases. Mitigating actions included closing the unit to new admissions, creating alternate care areas in the emergency psychiatric unit, and separating patients into “exposed but negative” and “infected” cohorts and housing them in “red,” and “yellow” zones, respectively. A “green” zone was created by clearance of positive cases. For the cohort exposed to COVID-19, masking was enforced by supervision, dining was scheduled in batches, and daily symptom screening and antigen testing were performed in addition to standard postexposure RT-PCR testing on day 4 and day 7. Mandatory N95 respirators and eye protection were implemented for staff on unit entry. Exposed staff followed employee health protocols for postexposure testing. Enhanced environmental control measures included terminal cleaning and UV-C disinfection of common areas and patient rooms and a thorough investigation of airflow. Discharged patients were contacted if they were residing in congregate facilities. Results: Of 47 patients, 39 (83%) tested positive for COVID-19. However, 8 patients remained negative; all 8 had received at least their primary vaccine series (Table 1). In total, 16 HCWs were SARS-CoV-2 positive in this outbreak. The outbreak officially ended 25 days after the first case. All SARS-CoV-2–positive patients had mild illness, not requiring treatment or hospitalization. We identified vaccine immune escape, staff presenteeism, patient noncompliance with masking, and comingling as major causes of transmission. We determined through contact tracing and temporality that the outbreak likely started from a positive staff member or visitor because most patients had been long-term residents. Conclusions: This outbreak was challenging due to the specialized behavioral needs of the involved patients. It was imperative to reopen this unit quickly and safely to provide psychiatric care to our county’s most vulnerable patients. Ongoing PPE education, repeated reinforcement, engagement in staff wellness to combat pandemic fatigue, and aggressive vaccination are all crucial to minimizing the impact of future outbreaks.Disclosures: None