COVID-19 control in the United States: the case for masking.

As of May 2021, the United States remains the world leader with 33 million of 165 million cases worldwide (20%) and 590,000 of 3.4 million deaths worldwide (17%) from COVID-19. Achieving herd immunity by disease spread and vaccination may result in 2 million to 4 million total US deaths. The future perfect of the vaccine should not be the enemy of the present good, which is masking. Masking, especially when combined with social distancing, crowd avoidance, frequent hand and face washing, increased testing capabilities, and contact tracing, is likely to prevent at least as many premature deaths as the widespread utilization of an effective and safe vaccine. Worldwide, masking is the oldest and simplest engineered control to prevent transmission of respiratory pathogens. Masking has been a cornerstone of infection control in hospitals, operating rooms, and clinics for more than a century. Unfortunately, since the epidemic began in the United States, masking has become politicized. All countries, but especially the United States, must adopt masking as an urgent necessity and a component of coordinated public health strategies to combat the COVID-19 pandemic. Any economic advantages of pandemic politics are short-lived and shortsighted in comparison with public health strategies of proven benefit that can prevent needless and mostly avoidable premature deaths from COVID-19. During the worst epidemic in more than 100 years, most Americans (75%) trust their health care providers. As competent and compassionate health care professionals, we recommend that effective strategies, especially masking, and not pandemic politics, should inform all rational clinical and public health decision-making.

Awareness and knowledge of COVID-19 infection control precautions and waste management among healthcare workers: Saudi cross-sectional study.

ABSTRACT: Healthcare workers (HWs) perform a critical role not only in the clinical management of patients but also in providing adequate infection control and prevention measures and waste management procedures to be implemented in healthcare facilities. The aim of this study was to evaluate the awareness and knowledge of COVID-19 infection control precautions and waste management procedures among HWs in Saudi Arabian hospitals.This was a descriptive, cross-sectional study. Information on knowledge, awareness, and practice of infection control and waste management procedures were obtained from the HWs using a structured questionnaire. A thematic analysis was used to analyze the data.Our findings indicated that most of the study participants were knowledgeable, with a mean score of 78.3%. In total, 92.5%, 90.3%, and 91.7% of the participants were aware of the infection control precautions, COVID-19 waste management procedures, the availability of infection control supplies, respectively. HWs' Knowledge regarding waste management and infection control procedures correlated significantly with sex (P ≤ .001 and <.001), education (P = .024 and .043), and working experience (P = .029 and .009), respectively.Most participants appreciated the importance of their role in infection control, surveillance, and monitoring of the ongoing safety practices in their patients as well as their facilities and communities.

Survey and enlightenment on the wearing of protective equipment of nurses working on the front line against COVID-19.

ABSTRACT: At present, coronavirus disease 2019 (COVID-19) remains a significant challenge for health workers around the world. This survey aims to highlight the status of the implementation of occupational protection measures for nurses working on the front line against COVID-19, and to analyze the problems in the process of wearing protective equipment.This cross-sectional study was conducted among 165 nurses who worked in COVID-19-stricken areas in China in March 2020. The questionnaire covered 3 aspects, namely: general information, the current condition of protective equipment wearing, and the wearing experience of protective equipment.A total of 160 (96.97%) valid questionnaires were collected. The average time of wearing protective equipment for the nurses surveyed was 6.38 ±â€Š3.30 hours per working day. For first-line nurses with low risk of infection, repeated wear of protective equipment was as follows: medical protective mask 30.77%, double latex gloves 8.46%, goggles/protective mask 15.38%, protective suit 15.38%; less wear of protective equipment were as follows: work cap 7.69%, surgical mask 7.69%, single layer latex gloves 30.77%, goggles/protective mask 30.77%, and isolation gown 46.15%. For nurses who were at moderate risk of infection, repeated wear of protective equipment was as follows: surgical mask 62.22%, goggles/protective mask 68.89%, and isolation gown 65.56%; less wear: work cap 3.33%, medical protective mask 15.56%, latex gloves 15.56%, goggles/protective mask 5.56%, and protective suit 16.67%. For front-line nurses with high risk of infection, repeated wear of protective equipment was as follows: surgical mask 64.91%, more than double latex gloves 8.77%, goggles/protective mask 75.44%, isolation gown 75.44%; less wear: work cap 1.75%, medical protective mask 1.75%, latex gloves 26.32%, goggles/ protective mask 1.75%, protective suit 1.75%. The main discomforts of wearing protective equipment were poor vision due to fogging (81.88%), stuffiness (79.38%), poor mobility (74.38%), sweating (72.5%), and skin damage (61.25%).More detailed personal protection standards should be developed, and the work load of nurses should be reduced. Actions should be taken to ensure the scientific implementation of personal protective measures. To solve practical clinical problems, future protective equipment may focus on the research and development of protective equipment applicable for different risk levels, as well as the research on integrated design, fabric innovation, and reusability.

A Survey of COVID-19 Preparedness Among Hospitals in Idaho.

BACKGROUND: SARS-CoV-2 has been implicated in the largest recorded coronavirus outbreak to date. Initially, most COVID-19 cases were in China, but the virus has spread to more than 184 countries worldwide, and the United States currently has more cases than any other country. OBJECTIVE: With person-to-person spread expanding in the United States, we describe hospital preparedness for managing suspected and confirmed COVID-19 patients. DESIGN: Cross-sectional survey focused on various elements of respiratory disease preparedness. SETTING: Critical access hospitals (CAHs) and acute-care hospitals (ACHs) in Idaho. METHODS: The electronic survey was sent to infection preventionists (IPs) and nurse administrators in 44 hospitals in Idaho. RESULTS: Overall, 32 (73%) hospitals responded to the survey. Participating facilities reported their preparedness with respect to existing, formalized structures for managing infectious disease incidents-specifically COVID-19-as well as availability of resources, such as isolation rooms and personal protective equipment, for safely managing suspected and confirmed COVID-19 cases. CONCLUSIONS: Hospitals covered by the survey had varying levels of preparedness for managing COVID-19 cases, with differences across the various categories of interest in this study. Although the study reveals strengths, including in application of emergency management and infection control frameworks, it also suggests that other areas, such as consistent implementation of federal guidelines and requirements for infection prevention, are potential areas for strengthening preparedness for SARS-CoV-2 and other respiratory pathogens with pandemic potential.

A qualitative study on safety perception among healthcare workers of a tertiary academic care center during the SARS-CoV-2 pandemic.

BACKGROUND: Protecting healthcare workers (HCWs) from exposure to SARS-CoV-2 during patient care is central to managing the current pandemic. Higher levels of trust in personal protective equipment (PPE) and infection prevention and control (IPC) strategies have been previously related to lower levels of emotional exhaustion, yet little is known on how to achieve such a perception of safety. We thus sought to identify institutional actions, strategies and policies related to HCWs' safety perception during the early phase of the pandemic at a tertiary care center in Switzerland by interviewing HCWs from different clinics, professions, and positions. METHODS: For this qualitative study, 36 face-to-face semi-structured interviews were performed. Interviews were based on a guide that addressed the perception of institutional strategies and policies during the first phase of the pandemic in March 2020. The participants included doctors (n = 19) and nurses (n = 17) in senior and non-senior positions from eight clinics in the University Hospital Basel, Switzerland, all involved in patient care. All interviews were audio-recorded and transcribed verbatim. Data were analyzed using qualitative content analysis and organized using MAXQDA (VERBI Software GmbH, Berlin). FINDINGS: Five recurring themes were identified to affect HCWs' perception of their safety during the SARS-CoV-2 pandemic: (1) transparency and clarity of information, (2) communication on the availability of PPE (with the provision of information alone increasing the feeling of safety even if supplies of PPE were reported as low), (3) uniformity and consistency of guidelines, (4) digital resources to support face-to-face teaching (although personal information transfer is still being considered superior in terms of strengthening safety perception) and (5) support and appreciation for the work performed. CONCLUSIONS: This study identifies institutional policies and actions influencing HCWs' safety perception during the first wave of the COVID-19 pandemic, the most important of which is the factor of transparent communication. This knowledge reveals potential areas of action critical to improving preparedness and management in hospitals faced with an infectious disease threat.

The experience of European hospital-based health care workers on following infection prevention and control procedures and their wellbeing during the first wave of the COVID-19 pandemic.

BACKGROUND: Working under pandemic conditions exposes health care workers (HCWs) to infection risk and psychological strain. A better understanding of HCWs' experiences of following local infection prevention and control (IPC) procedures during COVID-19 is urgently needed to inform strategies for protecting the psychical and psychological health of HCWs. The objective of this study was therefore to capture the perceptions of hospital HCWs on local IPC procedures and the impact on their emotional wellbeing during the first wave of the COVID-19 pandemic in Europe. METHODS: Participants were recruited in two sampling rounds of an international cross-sectional survey. Sampling took place between 31 March and 17 April 2020 via existing research networks and between 14 May and 31 August 2020 via online convenience sampling. Main outcome measures were behavioural determinants of HCWs' adherence to IPC guidelines and the WHO-5 Well-Being Index, a validated scale of 0-100 reflecting emotional wellbeing. The WHO-5 was interpreted as a score below or above 50 points, a cut-off score used in previous literature to screen for depression. RESULTS: 2289 HCWs from 40 countries in Europe participated. Mean age was 42 (±11) years, 66% were female, 47% and 39% were medical doctors and nurses, respectively. 74% (n = 1699) of HCWs were directly treating patients with COVID-19, of which 32% (n = 527) reported they were fearful of caring for these patients. HCWs reported high levels of concern about COVID-19 infection risk to themselves (71%) and their family (82%) as a result of their job. 40% of HCWs considered that getting infected with COVID-19 was not within their control. This feeling was more common among junior than senior HCWs (46% versus 38%, P value < .01). Sufficient COVID-19-specific IPC training, confidence in PPE use and institutional trust were positively associated with the feeling that becoming infected with COVID-19 was within their control. Female HCWs were more likely than males to report a WHO-5 score below 50 points (aOR 1.5 (95% confidence interval (CI) 1.2-1.8). CONCLUSIONS: In Europe, the COVID-19 pandemic has had a differential impact on those providing direct COVID-19 patient care, junior staff and women. Health facilities must be aware of these differential impacts, build trust and provide tailored support for this vital workforce during the current COVID-19 pandemic.

Infection control measures to prevent outbreaks of COVID-19 in Quebec hemodialysis units: a cross-sectional survey.

BACKGROUND: Limited space and resources are potential obstacles to infection prevention and control (IPAC) measures in in-centre hemodialysis units. We aimed to assess IPAC measures implemented in Quebec's hemodialysis units during the spring of 2020, describe the characteristics of these units and document the cumulative infection rates during the first year of the COVID-19 pandemic. METHODS: For this cross-sectional survey, we invited leaders from 54 hemodialysis units in Quebec to report information on the physical characteristics of the unit and their perceptions of crowdedness, which IPAC measures were implemented from Mar. 1 to June 30, 2020, and adherence to and feasibility of appropriate IPAC measures. Participating units were contacted again in March 2021 to collect information on the number of COVID-19 cases in order to derive the cumulative infection rate of each unit. RESULTS: Data were obtained from 38 of the 54 units contacted (70% response rate), which provided care to 4485 patients at the time of survey completion. Fourteen units (37%) had implemented appropriate IPAC measures by 3 weeks after Mar. 1, and all 38 units had implemented them by 6 weeks after. One-third of units were perceived as crowded. General measures, masks and screening questionnaires were used in more than 80% of units, and various distancing measures in 55%-71%; reduction in dialysis frequency was rare. Data on cumulative infection rates were obtained from 27 units providing care to 4227 patients. The cumulative infection rate varied from 0% to 50% (median 11.3%, interquartile range 5.2%-20.2%) and was higher than the reported cumulative infection rate in the corresponding region in 23 (85%) of the 27 units. INTERPRETATION: Rates of COVID-19 infection among hemodialysis recipients in Quebec were elevated compared to the general population during the first year of the pandemic, and although hemodialysis units throughout the province implemented appropriate IPAC measures rapidly in the spring of 2020, many units were crowded and could not maintain physical distancing. Future hemodialysis units should be designed to minimize airborne and droplet transmission of infection.

Impact of COVID-19 on hospital hand hygiene performance: a multicentre observational study using group electronic monitoring.

BACKGROUND: Reliable reports on hand hygiene performance throughout the COVID-19 pandemic are lacking as most hospitals continue to rely on direct observation to measure this quality indicator. Using group electronic hand hygiene monitoring, we sought to assess the impact of COVID-19 on adherence to hand hygiene. METHODS: Across 12 Ontario hospitals (5 university and 7 community teaching hospitals), a group electronic hand hygiene monitoring system was installed before the pandemic to provide continuous measurement of hand hygiene adherence across 978 ward and 367 critical care beds. We performed an interrupted time-series study of institutional hand hygiene adherence in association with a COVID-19 inpatient census and the Ontario daily count of COVID-19 cases during a baseline period (Nov. 1, 2019, to Feb. 29, 2020), the pre-peak period of the first wave of the pandemic (Mar. 1 to Apr. 24, 2020), and the post-peak period of the first wave (Apr. 25 to July 5, 2020). We used a Poisson regression model to assess the association between the hospital COVID-19 census and institutional hand hygiene adherence while adjusting for the correlation within inpatient units. RESULTS: At baseline, the rate of hand hygiene adherence was 46.0% (6 325 401 of 13 750 968 opportunities) and this improved beginning in March 2020 to a daily peak of 79.3% (66 640 of 84 026 opportunities) on Mar. 30, 2020. Each patient admitted with COVID-19 was associated with improved hand hygiene adherence (incidence rate ratio [IRR] 1.0621, 95% confidence interval [CI] 1.0619-1.0623). Increasing Ontario daily case count was similarly associated with improved hand hygiene (IRR 1.0026, 95% CI 1.0021-1.0032). After peak COVID-19 community and inpatient numbers, hand hygiene adherence declined and returned to baseline. INTERPRETATION: The first wave of the COVID-19 pandemic was associated with significant improvement in hand hygiene adherence, measured using a group electronic monitoring system. Future research should seek to determine whether strategies that focus on health care worker perception of personal risk can achieve sustainable improvements in hand hygiene performance.

Correlates of protection against symptomatic and asymptomatic SARS-CoV-2 infection.

The global supply of COVID-19 vaccines remains limited. An understanding of the immune response that is predictive of protection could facilitate rapid licensure of new vaccines. Data from a randomized efficacy trial of the ChAdOx1 nCoV-19 (AZD1222) vaccine in the United Kingdom was analyzed to determine the antibody levels associated with protection against SARS-CoV-2. Binding and neutralizing antibodies at 28 days after the second dose were measured in infected and noninfected vaccine recipients. Higher levels of all immune markers were correlated with a reduced risk of symptomatic infection. A vaccine efficacy of 80% against symptomatic infection with majority Alpha (B.1.1.7) variant of SARS-CoV-2 was achieved with 264 (95% CI: 108, 806) binding antibody units (BAU)/ml: and 506 (95% CI: 135, not computed (beyond data range) (NC)) BAU/ml for anti-spike and anti-RBD antibodies, and 26 (95% CI: NC, NC) international unit (IU)/ml and 247 (95% CI: 101, NC) normalized neutralization titers (NF50) for pseudovirus and live-virus neutralization, respectively. Immune markers were not correlated with asymptomatic infections at the 5% significance level. These data can be used to bridge to new populations using validated assays, and allow extrapolation of efficacy estimates to new COVID-19 vaccines.

Effects of dynamic response to coronavirus disease outbreak in a regional emergency medical center: A retrospective study.

ABSTRACT: Emergency departments (EDs) are on the frontline of the coronavirus disease (COVID-19) outbreak. To resolve the abrupt overloading of COVID-19-suspected patients in a community, each ED needs to respond in various ways. In our hospital, we increased the isolation beds through temporary remodeling and by performing in-hospital COVID-19 polymerase chain reaction testing rather than outsourcing them. The aim of this study was to verify the effects of our response to the newly developed viral outbreak.The medical records of patients who presented to an ED were analyzed retrospectively. We divided the study period into 3: pre-COVID-19, transition period of response (the period before fully implementing the response measures), and post-response (the period after complete response). We compared the parameters of the National Emergency Department Information System and information about isolation and COVID-19.The number of daily ED patients was 86.8 ±â€Š15.4 in the pre-COVID-19, 36.3 ±â€Š13.6 in the transition period, and 67.2 ±â€Š10.0 in the post-response period (P < .001). The lengths of stay in the ED were significantly higher in transition period than in the other periods [pre-COVID-19 period, 219.0 (121.0-378.0) min; transition period, 301 (150.0-766.5) min; post-response period, 281.0 (114.0-575.0) min; P < .001]. The ratios of use of an isolation room and fever (≥37.5°C) were highest in the post-response period [use of isolation room: pre-COVID-19 period, 0.6 (0.7%); transition period, 1.2 (3.3%); post-response period, 16.1 (24.0%); P < .001; fever: pre-COVID-19 period, 14.8(17.3%); transition period, 6.8 (19.1%); post-response period, 14.5 (21.9%), P < .001].During an outbreak of a novel infectious disease, increasing the number of isolation rooms in the ED and applying a rapid confirmation test would enable the accommodation of more suspected patients, which could help reduce the risk posed to the community and thus prevent strain on the local emergency medical system.

A pre-pandemic COVID-19 assessment of the costs of prevention and control interventions for healthcare associated infections in medical and surgical wards in Québec.

BACKGROUND: Healthcare-associated infections (HCAIs) present a major public health problem that significantly affects patients, health care providers and the entire healthcare system. Infection prevention and control programs limit HCAIs and are an indispensable component of patient and healthcare worker safety. The clinical best practices (CBPs) of handwashing, screening, hygiene and sanitation of surfaces and equipment, and basic and additional precautions (e.g., isolation, and donning and removing personal protective equipment) are keystones of infection prevention and control (IPC). There is a lack of rigorous IPC economic evaluations demonstrating the cost-benefit of IPC programs in general, and a lack of assessment of the value of investing in CBPs more specifically. OBJECTIVE: This study aims to assess overall costs associated with each of the four CBPs. METHODS: Across two Quebec hospitals, 48 healthcare workers were observed for two hours each shift, for two consecutive weeks. A modified time-driven activity-based costing framework method was used to capture all human resources (time) and materials (e.g. masks, cloths, disinfectants) required for each clinical best practice. Using a hospital perspective with a time horizon of one year, median costs per CBP per hour, as well as the cost per action, were calculated and reported in 2018 Canadian dollars ($). Sensitivity analyses were performed. RESULTS: A total of 1831 actions were recorded. The median cost of hand hygiene (N = 867) was 20 cents per action. For cleaning and disinfection of surfaces (N = 102), the cost was 21 cents per action, while cleaning of small equipment (N = 85) was 25 cents per action. Additional precautions median cost was $4.1 per action. The donning or removing or personal protective equipment (N = 720) cost was 76 cents per action. Finally, the total median costs for the five categories of clinical best practiced assessed were 27 cents per action. CONCLUSIONS: The costs of clinical best practices were low, from 20 cents to $4.1 per action. This study provides evidence based arguments with which to support the allocation of resources to infection prevention and control practices that directly affect the safety of patients, healthcare workers and the public. Further research of costing clinical best care practices is warranted.

Extended Epidemiological Models for Weak Economic Region: Case Studies of the Spreading of COVID-19 in the South Asian Subcontinental Countries.

The ascendancy of coronavirus has become widespread all around the world. For the prevention of viral transmission, the pattern of disease is explored. Epidemiological modeling is a vital component of the research. These models assist in studying various aspects of infectious diseases, such as death, recovery, and infection rates. Coronavirus trends across several countries may analyze sufficiently using SIR, SEIR, and SIQR models. Across this study, we propose two modified versions of the SEIRD method for evaluating the transmission of this infectious disease in the South Asian countries, more precisely, in the south Asian subcontinent. The SEIRD model is updated further by fusing some new factors, namely, isolation for the suspected people and recovery and death of the people who are not under the coverage of healthcare schemes or reluctant to receive treatment for various catastrophes. We will investigate the influences of those ingredients on public health-related issues. Finally, we will predict and display the infection scenario and relevant elements with the concluding remarks through the statistical analysis.

Enlightenment on oscillatory properties of 23 class B notifiable infectious diseases in the mainland of China from 2004 to 2020.

A variety of infectious diseases occur in mainland China every year. Cyclic oscillation is a widespread attribute of most viral human infections. Understanding the outbreak cycle of infectious diseases can be conducive for public health management and disease surveillance. In this study, we collected time-series data for 23 class B notifiable infectious diseases from 2004 to 2020 using public datasets from the National Health Commission of China. Oscillatory properties were explored using power spectrum analysis. We found that the 23 class B diseases from the dataset have obvious oscillatory patterns (seasonal or sporadic), which could be divided into three categories according to their oscillatory power in different frequencies each year. These diseases were found to have different preferred outbreak months and infection selectivity. Diseases that break out in autumn and winter are more selective. Furthermore, we calculated the oscillation power and the average number of infected cases of all 23 diseases in the first eight years (2004 to 2012) and the next eight years (2012 to 2020) since the update of the surveillance system. A strong positive correlation was found between the change of oscillation power and the change in the number of infected cases, which was consistent with the simulation results using a conceptual hybrid model. The establishment of reliable and effective analytical methods contributes to a better understanding of infectious diseases' oscillation cycle characteristics. Our research has certain guiding significance for the effective prevention and control of class B infectious diseases.

Impact of essential workers in the context of social distancing for epidemic control.

New emerging infectious diseases are identified every year, a subset of which become global pandemics like COVID-19. In the case of COVID-19, many governments have responded to the ongoing pandemic by imposing social policies that restrict contacts outside of the home, resulting in a large fraction of the workforce either working from home or not working. To ensure essential services, however, a substantial number of workers are not subject to these limitations, and maintain many of their pre-intervention contacts. To explore how contacts among such "essential" workers, and between essential workers and the rest of the population, impact disease risk and the effectiveness of pandemic control, we evaluated several mathematical models of essential worker contacts within a standard epidemiology framework. The models were designed to correspond to key characteristics of cashiers, factory employees, and healthcare workers. We find in all three models that essential workers are at substantially elevated risk of infection compared to the rest of the population, as has been documented, and that increasing the numbers of essential workers necessitates the imposition of more stringent controls on contacts among the rest of the population to manage the pandemic. Importantly, however, different archetypes of essential workers differ in both their individual probability of infection and impact on the broader pandemic dynamics, highlighting the need to understand and target intervention for the specific risks faced by different groups of essential workers. These findings, especially in light of the massive human costs of the current COVID-19 pandemic, indicate that contingency plans for future epidemics should account for the impacts of essential workers on disease spread.

The protective effect of tight-fitting powered air-purifying respirators during chest compressions.

BACKGROUND: Airborne personal protective equipment is required for healthcare workers when performing aerosol-generating procedures on patients with infectious diseases. Chest compressions, one of the main components of cardiopulmonary resuscitation, require intense and dynamic movements of the upper body. We aimed to investigate the protective effect of tight-fitting powered air-purifying respirators (PAPRs) during chest compressions. METHODS: This single-center simulation study was performed from February 2021 to March 2021. The simulated workplace protection factor (SWPF) is the concentration ratio of ambient particles and particles inside the PAPR mask; this value indicates the level of protection provided by a respirator when subjected to a simulated work environment. Participants performed continuous chest compressions three times for 2 min each time, with a 4-min break between each session. We measured the SWPF of the tight-fitting PAPR during chest compression in real-time mode. The primary outcome was the ratio of any failure of protection (SWPF <500) during the chest compression sessions. RESULTS: Fifty-four participants completed the simulation. Overall, 78% (n = 42) of the participants failed (the measured SWPF value was less than 500) at least one of the three sessions of chest compressions. The median value and interquartile range of the SWPF was 4304 (685-16,191). There were no reports of slipping down of the respirator or mechanical failure during chest compressions. CONCLUSIONS: Although the median SWPF value was high during chest compressions, the tight-fitting PAPR did not provide adequate protection.

A perspective on hospital-acquired (nosocomial) infection control of COVID-19: usefulness of spatial separation between wards and airborne isolation unit.

The coronavirus disease 2019 (COVID-19) pandemic has imposed a considerable burden on hospitals and healthcare workers (HCWs) worldwide, increasing the risk of outbreaks and nosocomial transmission to 'non-COVID-19' patients, who represent the highest-risk population in terms of mortality, and HCWs. Since HCWs are at the interface between hospitals on the one hand and the community on the other, they are potential reservoirs, carriers, or victims of severe acute respiratory syndrome coronavirus 2 cross-transmission. In addition, there has been a paradigm shift in the management of viral respiratory outbreaks, such as the widespread testing of patients and HCWs, including asymptomatic individuals. In hospitals, there is a risk of aerosol transmission in poorly ventilated spaces, and when performing aerosol-producing procedures, it is imperative to take measures against aerosol transmission. In particular, spatial separation of the inpatient ward for non-COVID-19 patients from that designated for patients with suspected or confirmed COVID-19 as well as negative-pressure isolation on the floor of the ward, using an airborne infection isolation device could help prevent nosocomial infection.

Infection control, occupational and public health measures including mRNA-based vaccination against SARS-CoV-2 infections to protect healthcare workers from variants of concern: A 14-month observational study using surveillance data.

BACKGROUND: We evaluated measures to protect healthcare workers (HCWs) in Vancouver, Canada, where variants of concern (VOC) went from <1% VOC in February 2021 to >92% in mid-May. Canada has amongst the longest periods between vaccine doses worldwide, despite Vancouver having the highest P.1 variant rate outside Brazil. METHODS: With surveillance data since the pandemic began, we tracked laboratory-confirmed SARS-CoV-2 infections, positivity rates, and vaccine uptake in all 25,558 HCWs in Vancouver Coastal Health, by occupation and subsector, and compared to the general population. Cox regression modelling adjusted for age and calendar-time calculated vaccine effectiveness (VE) against SARS-CoV-2 in fully vaccinated (≥ 7 days post-second dose), partially vaccinated infection (after 14 days) and unvaccinated HCWs; we also compared with unvaccinated community members of the same age-range. FINDINGS: Only 3.3% of our HCWs became infected, mirroring community rates, with peak positivity of 9.1%, compared to 11.8% in the community. As vaccine coverage increased, SARS-CoV-2 infections declined significantly in HCWs, despite a surge with predominantly VOC; unvaccinated HCWs had an infection rate of 1.3/10,000 person-days compared to 0.89 for HCWs post first dose, and 0.30 for fully vaccinated HCWs. VE compared to unvaccinated HCWs was 37.2% (95% CI: 16.6-52.7%) 14 days post-first dose, 79.2% (CI: 64.6-87.8%) 7 days post-second dose; one dose provided significant protection against infection until at least day 42. Compared with community infection rates, VE after one dose was 54.7% (CI: 44.8-62.9%); and 84.8% (CI: 75.2-90.7%) when fully vaccinated. INTERPRETATION: Rigorous droplet-contact precautions with N95s for aerosol-generating procedures are effective in preventing occupational infection in HCWs, with one dose of mRNA vaccination further reducing infection risk despite VOC and transmissibility concerns. Delaying second doses to allow more widespread vaccination against severe disease, with strict public health, occupational health and infection control measures, has been effective in protecting the healthcare workforce.