Risk of SARS-CoV-2 transmission by aerosols, the rational use of masks, and protection of healthcare workers from COVID-19

Mitigation strategies for airborne disease transmission in orchestras using computational fluid dynamics

The COVID-19 pandemic forced performing arts groups to cancel shows and entire seasons due to safety concerns for the audience and performers. It is unclear to what extent aerosols generated by wind instruments contribute to exposure because their fate is dependent on the airflow onstage. We use transient, second-order accurate computational fluid dynamics (CFD) simulations and quantitative microbial risk assessment to estimate aerosol concentrations and the associated risk and assess strategies to mitigate exposure in two distinct concert venues. Mitigation strategies involved rearranging musicians and altering the airflow by changing HVAC settings, opening doors, and introducing flow-directing geometries. Our results indicate that the proposed mitigation strategies can reduce aerosol concentrations in the breathing zone by a factor of 100, corresponding to a similar decrease in the probability of infection.

Perception Toward Exposure Risk of COVID-19 Among Health Workers in Vietnam: Status and Correlated Factors

Background: Hospital staff are at the frontline for the prevention and control of COVID-19. Understanding their perception of exposure risk is, therefore, important during the early phase of this pandemic. In this study, we evaluated the perception regarding risk of exposure to COVID-19 among Vietnamese hospital staff in Vietnam.

Method: A cross-sectional online study was carried out to collect demographic data and risk exposure perception during the second week of the national lockdown in April 2020 in Vietnam. Seven hundred and forty two hospital staff were recruited using the snowball sampling to answer 5-point Likert scale questions regarding their risk exposure perception. Exploratory factor analysis (EFA) was used to examine the construct validity of the questionnaire. Pearson coefficient analysis and multivariable regression models were applied to identify factors associated with the perceived COVID-19 exposure risk.

Results: Participants perceived a high risk of being infected with SARS-CoV-2 (score = 3.4, SD = 0.8). They also perceived the workplace response to COVID-19 as inadequate (score = 2.0, SD = 0.5). In particular, participants who worked in the emergency or intensive care departments were more likely to perceive an exposure risk, compared to those in infectious disease control departments (Coef. = −0.38, 95%CI: −0.74; −0.02). Participants from central regions perceived a lower risk of exposure to COVID-19 than those from northern regions (OR = 0.52, 95%CI: 0.28–0.96). Nurses were less likely than doctors to report being at risk of exposure to COVID-19 (OR = 0.56, 95%CI: 0.33–0.95).

Conclusions: We identified a high level of perceived risk regarding COVID-19 exposure among hospital staff during the unprecedented lockdown period in Vietnam. A comprehensive approach, incorporating improved risk communications, safety training and psychological support programs, for all hospital staff, including nurses and those residing in high population density areas, might further strengthen the national effort to control the pandemic.

How to address SARS-CoV-2 airborne transmission to ensure effective protection of healthcare workers? A review of the literature

SARS-CoV-2 mainly infects the respiratory tract, and presents significantly higher active replication in the upper airways. To remain viable and infectious, the SARS-CoV-2 virion must be complete and integral, which is not easily demonstrated in the environment by positive reverse transcriptase PCR results. Real-life conditions in healthcare settings may be conducive to SARS-CoV-2 RNA dissemination in the environment but without evidence of its viability and infectiveness in air. Theoretically, SARS-CoV-2 shedding and dissemination nonetheless appears to be air-mediated, and a distinction between “air” and “droplet” transmission is too schematic to reflect the reality of the respiratory particles emitted by patients, between which a continuum exists. Airborne transmission is influenced by numerous environmental conditions that are not transposable between different viral agents and situations in healthcare settings or in the community. Even though international guidelines on “droplet” versus “air” precautions and personal protective equipment (surgical versus respirator masks) are under discussion, the existing literature underscores the effectiveness of “droplet” precautions as a means of protecting healthcare workers. Differentiation in guidelines between healthcare venues, community settings and, more generally, confined environments is of paramount importance, especially insofar as it underlines the abiding pandemic-related need for systematic mask wearing by the general population.

Aerosolised fluorescein can quantify FFP mask faceseal leakage: a cost-effective adaptation to the existing point of care fit test

BACKGROUND

A qualitative fit test using bitter-tasting aerosols is the commonest way to determine filtering face-piece (FFP) mask leakage. This taste test is subjective and biased by placebo. We propose a cheap, quantitative modification of the taste test by measuring the amount of fluorescein stained filter paper behind the mask using image analysis.

METHODS

A bitter-tasting fluorescein solution was aerosolised during mask fit tests, with filter paper placed on masks' inner surfaces. Participants reported whether they could taste bitterness to determine taste test 'pass' or 'fail' results. Filter paper photographs were digitally analysed to quantify total fluorescence (TF).

RESULTS

Fifty-six healthcare professionals were fit tested; 32 (57%) 'passed' the taste test. TF between the taste test 'pass' and 'fail' groups was significantly different (p<0.001). A cut-off (TF = 5.0 × 10⁶ units) was determined at precision (78%) and recall (84%), resulting in 5/56 participants (9%) reclassified from 'pass' to 'fail' by the fluorescein test. Seven out of 56 (12%) reclassified from 'fail' to 'pass'.

CONCLUSION

Fluorescein is detectable and sensitive at identifying FFP mask leaks. These low-cost adaptations can enhance exiting fit testing to determine 'pass' and 'fail' groups, protecting those who 'passed' the taste test but have high fluorescein leak, and reassuring those who 'failed' the taste test despite having little fluorescein leak.

SARS-CoV-2 Infection in Healthcare Professionals and General Population During "First Wave" of COVID-19 Pandemic: A Cross-Sectional Study Conducted in Sicily, Italy

On December 31, 2019, an outbreak of lower respiratory infections was documented in Wuhan caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the beginning, SARS-CoV-2 has caused many infections among healthcare workers (HCWs) worldwide. Aims of this study were: a. to compare the distribution among the HCWs and the general population of SARS-CoV-2 infections in Western Sicily and Italy; b. to describe the characteristics of HCWs infected with SARS-CoV-2 in the western Sicilian healthcare context during the first wave of the epidemic diffusion in Italy. Incidence and mean age of HCWs infected with SARS-CoV-2 were comparable in Western Sicily and in the whole Italian country. The 97.6% of infections occurred in HCWs operating in non-coronavirus disease 2019 (COVID-19) working environments, while an equal distribution of cases between hospital and primary care services context was documented. Nurses and healthcare assistants, followed by physicians, were the categories more frequently infected by SARS-CoV-2. The present study suggests that healthcare workers are easily infected compared to the general population but that often infection could equally occur in hospital and non-hospital settings. Safety of HCWs in counteracting the COVID-19 pandemic must be strengthened in hospital [adequate provision of personal protective equipment (PPE), optimization of human resources, implementation of closed and independent groups of HCWs, creation of traffic control building and dedicated areas in every healthcare context] and non-hospital settings (influenza vaccination, adequate psychophysical support, including refreshments during working shifts, adequate rest, and family support).

Determinants of Face Mask Utilization to Prevent Covid-19 Pandemic among Quarantined Adults in Tigrai Region, Northern Ethiopia, 2020

A face mask is a vital component of personal protective equipment to prevent potentially contagious respiratory infections. There was a lack of evidence showing the proportion and determinants of face mask use in Ethiopia. Therefore, this study aimed to identify face mask utilization determinants to prevent spread of the Covid-19 pandemic among quarantined adults in Tigrai region, northern Ethiopia. A total of 331 participants selected using a systematic random sampling method were included in the study. An interviewer-administered questionnaire was employed. After describing the variables using frequencies, means, and standard deviations, multivariable logistic regression determined factors associated with face mask utilization to prevent COVID-19 spread. The study participants were primarily males (70%) and mean age was 30.5 (SD = 11) years. Nearly half of the participants reported they did not wear a face mask when leaving home. Face mask utilization was significantly associated with knowledge score, employment status, gender, age, and educational status of the study participants.

Cardiopulmonary Exercise Testing in the Coronavirus Disease - 2019 Era: Safety and Protocol Considerations

ABSTRACT

Cardiopulmonary exercise testing (CPX) is a valuable tool in both clinical practice and research settings. Therefore, it is advantageous for human performance laboratories to continue operating during the coronavirus disease 2019 (COVID-19) pandemic. All institutions should adhere to general COVID-19 guidelines provided by the Centers for Disease Control. Because of the testing environment, CPX laboratories must consider additional precautionary safety measures. This article provides recommendations for modifying the CPX protocol to ensure safety for all stakeholders during the pandemic. These modifications are universal across all populations, types of institutions and testing modalities. Preliminary measures include careful review of federal, local, and institutional mandates. The description outlines how to evaluate a testing environment and alter workflow. Guidelines are provided on what specific personal protective equipment should be acquired; as well as necessary actions before, during, and after the CPX test. These precautions will limit the possibility of both clients and staff from contracting or spreading the disease while maintaining testing volume in the laboratory.

Impacto de la introducción del cubrebocas contra el COVID-19: una revisión narrativa

El objetivo de este trabajo fue identificar el impacto de la introducción del cubrebocas contra el COVID-19: qué características tiene y cómo se ha introducido alrededor del mundo. Para ello, se realizó una revisión de la literatura disponible en una base de datos especializada, PUBMED, la cual se ajustó a las directrices enmarcadas en la metodología PRISMA . Se definieron ecuaciones de búsqueda bajo los términos MeSH: humans, COVID-19, severe acute respiratory síndrome coronavirus 2, masks y equipment design, utilizando el carácter booleano AND. Con estas ecuaciones se buscaron artículos publicados en 2020, recuperando 676 registros en total, eligiendo 82 que abordan el tema de interés e incluyendo en la revisión final 49 artículos que cumplían con todos los criterios de inclusión y exclusión definidos. Los resultados sugieren que la introducción de mascarillas tuvo un impacto positivo para reducir el riesgo de COVID-19 y el uso inadecuado del cubrebocas es un factor de riesgo.

Evaluation of masks' internal and external surfaces used by health care workers and patients in coronavirus-2 (SARS-CoV-2) wards

One of the simplest and most effective individual measures is to wear a mask to prevent the spread of respiratory droplets from carriers to healthy people and patients admitted to corona wards and their staff. This research aimed to investigate the contamination of internal and external surfaces of various masks used by patients and staff with SARS coronavirus, as well as the possibility of airborne transmission in Imam Khomeini Hospital, Ardabil. For this purpose, twenty-five staff members and ten patients participated voluntarily in this cross-sectional study. Sampling was performed using swaps on both sides (inside and outside) of various surgical masks, N-95, and filtering face piece FFP2 through standard methods in compliance with the relevant conditions and from a surface of at least 5 cm². Next, the collected samples were immediately transferred to a laboratory and analyzed by real-time PCR method to detect the presence of SARS-CoV-2 virus after viral genome extraction. Based on the obtained results, from a total of 30 collected samples (25 of personnel masks plus 5 samples of hospitalized patients' masks). A total of 60 masks were sampled. For every collected sample, the researchers studied both inside and outside of the mask. Upon analyzing the data, it was showed that 6 mask samples were positive for the presence of coronavirus. Nonetheless, all samples taken from both inside and outside of the personnel masks (N-95 and FFP2 types of masks) were negative. Among the 6 positive samples, four cases were related to the internal part, one case to the outer part of the three-layer surgical masks, and one to the outer part of the N-95 masks in hospitalized patients. As masks reduce the concentration of virus particles, they can play an important role in creating immunity.

A cost-effective plan for global testing - an infection rate stratified, algorithm guided, multiple-level, continuously pooled testing strategy

The most effective measure to prevent or stop the spread of infectious diseases is the early identification and isolation of infected individuals through comprehensive screening. At present, in the COVID-19 pandemic, such screening is often limited to isolated regions as determined by local governments. Screening of potentially infectious individuals should be conducted through coordinated national or global unified actions. Our current research focuses on using resources to conduct comprehensive national and regional regular testing with a risk rate based, algorithmic guided, multiple-level, pooled testing strategy. Here, combining methodologies with mathematical logistic models, we present an analytic procedure of an overall plan for coordinating state, national, or global testing. The proposed plan includes three parts 1) organization, resource allocation, and distribution; 2) screening based on different risk levels and business types; and 3) algorithm guided, multiple level, continuously screening the entire population in a region. This strategy will overcome the false positive and negative results in the polymerase chain reaction (PCR) test and missing samples during initial tests. Based on our proposed protocol, the population screening of 300,000,000 in the US can be done weekly with between 15,000,000 and 6,000,000 test kits. The strategy can be used for population screening for current COVID-19 and any future severe infectious disease when drugs or vaccines are not available.

SARS-CoV-2 Ig G among Healthcare Workers and the General Population

It is assumed that healthcare workers are at the highest risk to be infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, few data from healthcare workers who do not primarily take care of patients with SARS-CoV-2 infection support this assumption. We investigated the prevalence of immunoglobulin G (Ig G) against SARS-CoV-2 among healthcare workers who do not primarily take care of patients with SARS-CoV-2 infection and the general population in a well-defined geographical area. The first part of the study was conducted in May 2020 in Val Mesolcina (Southern Switzerland), a valley with ~8000 inhabitants. All healthcare workers were invited. All participants (n = 488) of the Swiss Longitudinal Cohort Study (SWICOS), a cohort representative of the general population, were also invited. Circulating Ig G against spike protein subunit 1 of SARS-CoV-2 were tested in each subject. Subjects with positive Ig G were tested again after 6 months. The condition of being a healthcare worker, rather than a part of the general population, was tested as a predictor of seroprevalence positivity by both simple and multiple (adjusted for age and sex) logistic regression. Eleven (2.6%) of the 423 SWICOS participants and 46 (16%) out of 289 healthcare workers were positive for antibodies against SARS-CoV-2. The seroprevalence OR was 7.01 (95% CI: 3.53–15.47) for healthcare workers as compared to SWICOS participants. After adjusting for age and gender, the seroprevalence OR was 5.13 (95% CI: 2.54–10.40). About three quarters of the subjects in the SWICOS (73%) and in healthcare (79%) group with a previous positive serology still presented positive Ig G against the SARS-CoV-2 after 6 months. The present seroprevalence data point out that the SARS-CoV-2 infection is seven times higher among healthcare workers than in the general population of Val Mesolcina. Efforts to effectively protect all the healthcare personnel are needed.

Perceived stress and affecting factors related to COVID-19 pandemic of emergency nurses in Turkey

Aim

To examine the perceived stress and affecting factors related to the COVID‐19 pandemic of emergency nurses at the first stage of the pandemic.

Background

During pandemic process, nurses reported to experience stress due to a very high risk of being infected and hard work.

Method

A descriptive study. The sample of the study consisted of 169 emergency nurses. To collect data, a personal information form was used together with the Perceived Stress Scale.

Results

The factors that significantly affect the perceived stress score of emergency nurses during the COVID‐19 pandemic included applying respiratory isolation, changing the way of life, not being able to access protective equipment, insufficient nurses in the unit and thinking that COVID‐19 will be transmitted to oneself.

Conclusion

Nearly half of the emergency nurses perceived stress above average during pandemic, and their working conditions affected this situation.

Implications for Nursing Management

Meeting physiological needs and applying psychological guidance and counselling interventions in the stress management of emergency nurses may contribute to the reduction of their stress levels. Effective infection control, reducing workload, increasing the number of nurses and strengthening the coping mechanisms can minimize the perceived stress level of emergency nurses.

Protection From COVID-19

BACKGROUND

Since the beginning of 2020 the SARS-CoV-2 virus has spread to nearly every country in the world. The mainly airborne pathogen has led to large numbers of deaths, principally in elderly and vulnerable segments of the population. Protective vaccines have recently become available, but it is not yet clear whether and when population-wide immunity will be achieved. The existence of evidence for the protective effect of masks covering the mouth and nose is a topic of public debate.

METHODS

A selective literature search was carried out in PubMed. Data from the German Robert Koch Institute and the Centers for Disease Control and Prevention were also taken into account.

RESULTS

When talking, as many as 20 000 droplets ranging in size from 20 to 500 μM are released every second. According to PCR tests, the amount of virus exhaled is highest immediately before the onset of symptoms. No randomized trials have been conducted on the effect of masks covering the mouth and nose. A metaanalysis of 29 studies on infection with SARS-CoV-2, SARS, or MERS revealed that type N-95 masks (corresponding approximately to FFP-2), surgical masks, or similar multilayer cotton masks can greatly reduce the infection risk for the wearers (RR 0.34 [0.26; 0.45], with moderate heterogeneity [I2 = 48%]). Model experiments and case reports suggest that masks covering the mouth and nose afford considerable protection against transmission of SARS-CoV-2 and other airborne diseases by reducing release of and exposure to potentially infectious droplets; in addition, infections that do occur take a milder course. A limitation of the studies analyzed is that in most cases, this effect cannot be viewed in isolation from the protective impact of other measures (distancing, hygiene precautions).

CONCLUSION

It can plausibly be assumed that consistent use of masks covering the mouth and nose can play an important role in containing the spread of SARSCoV- 2.

Knowledge and Perception of COVID-19 Pandemic during the First Wave (Feb-May 2020): A Cross-Sectional Study among Italian Healthcare Workers

Italy was the first country in Europe to face the coronavirus pandemic. The aim of the study was to analyze healthcare workers’ (HCWs) level of information, practice, and risk perception towards COVID-19. We set up a cross-sectional study through SurveyMonkey^® and distributed the link through Facebook and Whatsapp closed groups. The research instrument was a 31 items questionnaire distributed using Facebook and Whatsapp. It was conducted in Italy from February to May 2020. The study participants were general practitioners, pediatricians and other health professionals. A total of 958 participants were included: 320 (33.4%) general practitioners, 248 (25.9%) pediatricians and 390 (40.7%) other health professionals. The highest response rate was from Northern Italy (48.1%), followed by Central Italy (29.9%) and Southern Italy (22.0%). Less than a half (46%) of respondents felt they had a good level of information of COVID-19 case definition and of national prevention guidelines. Respondents reported to have changed their clinical practice; particularly, they increased the use of masks (87.1%, p < 0.001), disinfection and sanitization of doctors’ offices (75.8%, p < 0.001), the use of protective glasses (71.2%, p < 0.001), alcoholic hand solution (71.2%, p < 0.001), and hand washing (31.8%, p = 0.028). HCWs are at high risk of infection; less than a half of them felt adequately prepared to face COVID-19 pandemic, so they need extensive information and awareness of the disease to take adequate precautionary measures, and they are crucial to disseminate good practices.

Attitudes and beliefs of Spanish healthcare professionals during the COVID-19 pandemic

During the COVID-19 pandemic, healthcare professionals are taking the risk of becoming infected or infecting their families. Spain is the country with the highest number of infected healthcare professionals worldwide. Our aim was to study the attitudes and beliefs of these professionals during the current pandemic. Descriptive study conducted by using an online questionnaire-based on an earlier one-which was sent to healthcare professionals at the national level, during the week March 20-27, 2020. Healthcare professionals returned 971 completed questionnaires. A total of 803 (82.7%) participants thought that they did not have suitable PPEs (Personal Protective Equipment) to protect them from infection with COVID-19. In addition, even 229 (23.58%) agreed to go on working even if they were not. In spite of this, 606 (62.4%) of them were ready to work, even with a higher-than-usual risk of becoming infected at work and getting ill. Remarkably high professional commitment has been observed among Spanish healthcare workers in the current pandemic. They were ready to work even when many of them considered that they did not have suitable PPEs, and were thus taking a higher than usual infection risk. However, they put the health of their relatives before their duties at work.

Prevalence of SARS-CoV-2 antibodies in pediatric healthcare workers

Objectives

To determine SARS-CoV-2-antibody prevalence in pediatric healthcare workers (pHCWs).

Design

Baseline prevalence of anti-SARS-CoV-2-IgG was assessed in a prospective cohort study from a large pediatric healthcare facility. Prior SARS-CoV-2 testing history, potential risk factors and anxiety level about COVID-19 were determined. Prevalence difference between emergency department (ED)-based and non-ED-pHCWs was modeled controlling for those covariates. Chi-square test-for-trend was used to examine prevalence by month of enrollment.

Results

Most of 642 pHCWs enrolled were 31-40years, female and had no comorbidities. Half had children in their home, 49% had traveled, 42% reported an illness since January, 31% had a known COVID-19 exposure, and 8% had SARS-CoV-2 PCR testing. High COVID-19 pandemic anxiety was reported by 71%. Anti-SARS-CoV-2-IgG prevalence was 4.1%; 8.4% among ED versus 2.0% among non-ED pHCWs (p < 0.001). ED-work location and known COVID-19 exposure were independent risk factors. 31% of antibody-positive pHCWs reported no symptoms. Prevalence significantly (p < 0.001) increased from 3.0% in April–June to 12.7% in July–August.

Conclusions

Anti-SARS-CoV-2-IgG prevalence was low in pHCWs but increased rapidly over time. Both working in the ED and exposure to a COVID-19-positive contact were associated with antibody-seropositivity. Ongoing universal PPE utilization is essential. These data may guide vaccination policies to protect front-line workers.

Mask Wearing Hesitancy During the COVID-19 Pandemic in South Iran

Purpose:

The aim of the current study was to investigate the prevalence of face mask wearing among different groups of people in south Iran. We also investigated the associations between mask wearing hesitancy and various factors.

Methods:

We surveyed a sample (convenience sampling) of 5 groups of people: general population, people with epilepsy, people with diabetes mellitus (DM), people with cardiac problems, and people with psychiatric problems. The survey included 4 general questions (age, sex, education, and medical/psychiatric problem) and 4 coronavirus disease 2019 (COVID-19)-specific questions (contracting COVID-19, relatives with COVID-19, wearing a face mask while in crowded places, and the frequency of daily hand washings).

Results:

A total of 582 people (153 people with epilepsy, 127 patients with DM, 98 people with cardiac problems, 96 patients with psychiatric disorders, and 108 healthy individuals) participated. Twenty-eight (4.8%) people expressed that they do not wear a face mask when at crowded places. A lower education and less frequent daily hand washings had associations with mask wearing hesitancy.

Conclusions:

Mask wearing hesitancy is a concern during a respiratory viral disease pandemic. Paying attention to personal variables, especially if they are modifiable (eg, education and hygiene), is probably productive and practical in promoting mask wearing culture.

Face Mask-Related Ocular Surface Modifications During COVID-19 Pandemic: A Clinical, In Vivo Confocal Microscopy, and Immune-Cytology Study

Purpose

The purpose of this study was to describe the face mask (FM)-related ocular surface changes using clinical tests, in vivo confocal microscopy (IVCM) and impression cytology (IC), and to investigate the Dry Eye-related Quality of life Score (DEQS).

Methods

Sixty-six patients with dry eye disease (DED) and 62 healthy subjects (group 2) using FM were enrolled. Groups were divided into: groups 1A and 2A: < 3 hours of FM wear; groups 1B and 2B: 3 to 6 hours; and groups 1C and 2C: > 6 hours. Patients underwent DEQS questionnaire, break-up time (BUT), Schirmer test I (STI), fluorescein and lissamine staining (FS and LS), IVCM to determine corneal dendritic cell density (DCD) and goblet cell density (GCD), and IC to measure HLA-DR, at baseline and after 3 months.

Results

FM use duration before enrollment was 27 ± 2.3 and 30 ± 4.1 (days ± SD) for groups 1 and 2 (P > 0.05). After 3 months, DEQS worsened in groups 1B and 1C, STI in groups 1A to 1C, FS and LS in group 1C (P < 0.05); in controls, BUT and FS worsened only in group 2C (P < 0.05). DCD significantly increased in groups 1A to 1C and HLA-DR in groups 1B and 1C (P < 0.05), whereas GCD did not significantly change. DCD and HLA-DR increased only in group 2C (P < 0.05). DEQS significantly correlated with DCD (P = 0.05, r = 0.698; P < 0.001, r = 0.832) and HLA-DR (P = 0.043, r = -0.687; P < 0.001, r = 0.861) at baseline and 3 months.

Conclusions

Use of FM increases ocular surface inflammation and negatively impacts the quality of life in patients with DED.

Translational Relevance

The study of the prolonged use of FM effects may be relevant to managing DED.

Airborne transmission of virus-laden aerosols inside a music classroom: Effects of portable purifiers and aerosol injection rates

The ongoing COVID-19 pandemic has shifted attention to the airborne transmission of exhaled droplet nuclei within indoor environments. The spread of aerosols through singing and musical instruments in music performances has necessitated precautionary methods such as masks and portable purifiers. This study investigates the effects of placing portable air purifiers at different locations inside a classroom and the effects of different aerosol injection rates (e.g., with and without masks, different musical instruments, and different injection modes). Aerosol deposition, airborne concentration, and removal are analyzed in this study. It was found that using purifiers could help in achieving ventilation rates close to the prescribed values by the World Health Organization, while also achieving aerosol removal times within the Center of Disease Control and Prevention recommended guidelines. This could help in deciding break periods between classroom sessions, which was around 25 min through this study. Moreover, proper placement of purifiers could offer significant advantages in reducing airborne aerosol numbers (offering several orders of magnitude higher aerosol removal when compared to nearly zero removal when having no purifiers), and improper placement of the purifiers could worsen the situation. This study suggests the purifier to be placed close to the injector to yield a benefit and away from the people to be protected. The injection rate was found to have an almost linear correlation with the average airborne aerosol suspension rate and deposition rate, which could be used to predict the trends for scenarios with other injection rates.

Systemic Management of Pandemic Risks in Dental Practice: A Consolidated Framework for COVID-19 Control in Dentistry

Dental teams and their workplaces are among the most exposed to airborne and bloodborne infectious agents, and therefore at the forefront of pandemic-related changes to how dental care is organized and provided to patients. The increasing complexity of guidelines makes is challenging for clinicians to navigate the multitude of COVID-19 guidelines issued by different agencies. A comparative analysis of guidance issued for managing COVID-19 in dental settings leading U.S. agencies was conducted, including documents of the Occupational Safety and Health Administration (OSHA), an agency of the U.S. Secretary of Labor, and of the U.S. Centers for Disease Prevention and Control (CDC), an agency of the U.S. Secretary of Health and Human Services. Details of infection control and other risk mitigation measures were reviewed for consistency, overlaps and similarities, then clustered according to thematic areas covering all domains of managing a dental healthcare setting. The analysis revealed five distinct areas of pandemic control, comprising (1) planning and protocols, (2) patient screening, (3) preparation of facilities, (4) PPE and infection control, and (5) procedures and aerosol control; thereby covering systematically all aspects requiring adaptation in a pandemic context. The "Pandemic-5 Framework for COVID-19 Control in Dentistry" provides an opportunity to simplify comprehensive decision-making from a clinical practitioner perspective. The framework supports a comprehensive systems-driven approach by using dental clinics as a setting to integrate pandemic clinical responses with the implementation of appropriate infection control protocols. Traditionally these two aspects are addressed independently from each other in separate concepts.

Droplet and bone dust contamination from high-speed drilling during mastoidectomy

OBJECTIVES

The aim of this study was to examine contamination from otolaryngologic procedures involving high-speed drilling, specifically mastoid surgery, and to assess the adequacy of PPE in such procedures.

DESIGN AND SETTING

Mastoid surgery was simulated in a dry laboratory using a plastic temporal bone, microscope and handheld drill with irrigation and suction. Comparisons of distance of droplet and bone dust contamination and surgeon contamination were made under differing conditions. Irrigation speed, use of microscope and drill burr size and type were compared.

MAIN OUTCOME MEASURES

Measurement of the distance of field contamination while performing simulated mastoidectomy and location of surgeon contamination.

RESULTS

There was a greater distance field contamination and surgeon contamination without the use of the microscope. Contamination was reduced by using a smaller drill burr and by using a diamond burr when compared to a cutting burr. The use of goggles and a face mask provided good protection for the surgeon. However, the microscope alone may provide sufficient protection to negate the need for goggles.

CONCLUSIONS

While the risks of performing mastoid surgery during the coronavirus pandemic cannot be completely removed, they can be mitigated. Such factors include using the microscope for all drilling, using smaller size drill burrs and creating a safe zone around the operating table.

Tracing surface and airborne SARS-CoV-2 RNA inside public buses and subway trains

Given the widespread concern but general lack of information over the possibility of SARS-CoV-2 infection in public transport, key issues such as passenger personal hygiene, efficient air circulation systems, and the effective disinfection of frequently touched surfaces need to be evaluated to educate the public and diminish the risk of viral transmission as we learn to live with the ongoing pandemic. In this context we report on a study involving the collection of 99 samples taken from inside Barcelona buses and subway trains in May to July 2020. From this sample group 82 (58 surface swabs, 9 air conditioning (a/c) filters, 3 a/c dust, 12 ambient air) were selected to be analysed by RT-PCR for traces of the SARS-CoV-2 virus. Thirty of these selected samples showed evidence for one or more of 3 target RNA gene regions specific for this virus (IP2, IP4, E). Most (24) of these 30 samples showed positivity for only 1 of the 3 RNA targets, 4 samples yielded 2 targets, and 2 samples provided evidence for all 3 targets. RNA remnants were more common in surface swabs from support bars (23 out of 58) than in ambient air inside the vehicles (3 out of 12), with relatively higher concentrations of viral RNA fragments in buses rather than in trains. Whereas subway train a/c filters examined were all virus-free, 4 of the 9 bus a/c filter/dust samples yielded evidence for viral RNA. After nocturnal maintenance and cleaning most buses initially yielding positive results subsequently showed elimination of the RT-PCR signal, although signs of viral RNA remained in 4 of 13 initially positive samples. The presence of such remnant viral traces however does not demonstrate infectivity, which in the present study is considered unlikely given the fragmentary nature of the gene targets detected. Nevertheless, best practice demands that close attention to ventilation systems and regular vehicle disinfection in public transport worldwide need to be rigorously applied to be effective at eliminating traces of the virus throughout the vehicle, especially at times when COVID-19 cases are peaking. Additionally, infectivity tests should be implemented to evaluate the efficiency of disinfection procedures to complement the information resulting from RT-PCR analysis. Modelling the probability of infection whilst travelling in buses under different scenarios indicates that forced ventilation greatly reduces the risk.

Nosocomial transmission and outbreaks of coronavirus disease 2019: the need to protect both patients and healthcare workers

OBJECTIVES

To compile current published reports on nosocomial outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), evaluate the role of healthcare workers (HCWs) in transmission, and evaluate outbreak management practices.

METHODS

Narrative literature review.

SHORT CONCLUSION

The coronavirus disease 2019 (COVID-19) pandemic has placed a large burden on hospitals and healthcare providers worldwide, which increases the risk of nosocomial transmission and outbreaks to "non-COVID" patients or residents, who represent the highest-risk population in terms of mortality, as well as HCWs. To date, there are several reports on nosocomial outbreaks of SARS-CoV-2, and although the attack rate is variable, it can be as high as 60%, with high mortality. There is currently little evidence on transmission dynamics, particularly using genomic sequencing, and the role of HCWs in initiating or amplifying nosocomial outbreaks is not elucidated. There has been a paradigm shift in management practices of viral respiratory outbreaks, that includes widespread testing of patients (or residents) and HCWs, including asymptomatic individuals. These expanded testing criteria appear to be crucial in identifying and controlling outbreaks.

Aerosol generation from different wind instruments

The potential airborne transmission of COVID-19 has raised significant concerns regarding the safety of musical activities involving wind instruments. However, currently, there is a lack of systematic study and quantitative information of the aerosol generation during these instruments, which is crucial for offering risk assessment and the corresponding mitigation strategies for the reopening of these activities. Collaborating with 15 musicians from the Minnesota Orchestra, we conduct a systematic study of the aerosol generation from a large variety of wind instruments under different music dynamic levels and articulation patterns. We find that the aerosol concentration from different brass and woodwinds exhibits two orders of magnitude variation. Accordingly, we categorize the instruments into low (tuba), intermediate (bassoon, piccolo, flute, bass clarinet, French horn, and clarinet) and high risk (trumpet, bass trombone, and oboe) levels based on a comparison of their aerosol generation with those from normal breathing and speaking. In addition, we observe that the aerosol generation can be affected by the changing dynamic level, articulation pattern, the normal respiratory behaviors of individuals, and even the usage of some special techniques during the instrument play. However, such effects vary substantially for different types of instrument, depending on specific breathing techniques as well as the tube structure and inlet design of the instrument. Overall, our findings can bring insights into the risk assessment of airborne decrease transmission and the corresponding mitigation strategies for various musical activities involving wind instrument plays, including orchestras, community and worship bands, music classes, etc.

SARS-COV-2 INFECTION AND LONGITUDINAL FECAL SCREENING IN MALAYAN TIGERS (PANTHERA TIGRIS JACKSONI), AMUR TIGERS (PANTHERA TIGRIS ALTAICA ), AND AFRICAN LIONS (PANTHERA LEO KRUGERI) AT THE BRONX ZOO, NEW YORK, USA

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged as the cause of a global pandemic in 2019-2020. In March 2020, New York City became the epicenter in the United States for the pandemic. On 27 March 2020, a Malayan tiger (Panthera tigris jacksoni) at the Bronx Zoo in New York City developed a cough and wheezing with subsequent inappetence. Over the next week, an additional Malayan tiger and two Amur tigers (Panthera tigris altaica) in the same building and three lions (Panthera leo krugeri) in a separate building also became ill. The index case was anesthetized for diagnostic workup. Physical examination and bloodwork results were unremarkable. Thoracic radiography and ultrasonography revealed a bronchial pattern with peribronchial cuffing and mild lung consolidation with alveolar-interstitial syndrome, respectively. SARS-CoV-2 RNA was identified by real-time, reverse transcriptase PCR (rRT-PCR) on oropharyngeal and nasal swabs and tracheal wash fluid. Cytologic examination of tracheal wash fluid revealed necrosis, and viral RNA was detected in necrotic cells by in situ hybridization, confirming virus-associated tissue damage. SARS-CoV-2 was isolated from the tracheal wash fluid of the index case, as well as the feces from one Amur tiger and one lion. Fecal viral RNA shedding was confirmed in all seven clinical cases and an asymptomatic Amur tiger. Respiratory signs abated within 1-5 days for most animals, although they persisted intermittently for 16 days in the index case. Fecal RNA shedding persisted for as long as 35 days beyond cessation of respiratory signs. This case series describes the clinical presentation, diagnostic evaluation, and management of tigers and lions infected with SARS-CoV-2 and describes the duration of viral RNA fecal shedding in these cases. This report documents the first known natural transmission of SARS-CoV-2 from humans to nondomestic felids.

Transition metal complexes as potential tools against SARS-CoV-2: anin silicoapproach

Screening of selected transition metal-based antiviral agents,in silico, predicted the potential inhibition of RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 which emerged as the potential drug candidate for COVID-19.

SARS-CoV-2 and Health Care Worker Protection in Low-Risk Settings: a Review of Modes of Transmission and a Novel Airborne Model Involving Inhalable Particles

Since the beginning of the COVID-19 pandemic, there has been intense debate over SARS-CoV-2's mode of transmission and appropriate personal protective equipment for health care workers in low-risk settings. The objective of this review is to identify and appraise the available evidence (clinical trials and laboratory studies on masks and respirators, epidemiological studies, and air sampling studies), clarify key concepts and necessary conditions for airborne transmission, and shed light on knowledge gaps in the field. We find that, except for aerosol-generating procedures, the overall data in support of airborne transmission-taken in its traditional definition (long-distance and respirable aerosols)-are weak, based predominantly on indirect and experimental rather than clinical or epidemiological evidence. Consequently, we propose a revised and broader definition of "airborne," going beyond the current droplet and aerosol dichotomy and involving short-range inhalable particles, supported by data targeting the nose as the main viral receptor site. This new model better explains clinical observations, especially in the context of close and prolonged contacts between health care workers and patients, and reconciles seemingly contradictory data in the SARS-CoV-2 literature. The model also carries important implications for personal protective equipment and environmental controls, such as ventilation, in health care settings. However, further studies, especially clinical trials, are needed to complete the picture.

Modelling the health and economic impacts of different testing and tracing strategies for COVID-19 in the UK

Background: Coronavirus disease 2019 (COVID-19) is resurgent in the UK and health and economic costs of the epidemic continue to rise. There is a need to understand the health and economic costs of different courses of action. Methods: We combine modelling, economic analysis and a user-friendly interface to contrast the impact and costs of different testing strategies: two levels of testing within the current test-trace-isolate (TTI) strategy (testing symptomatic people, tracing and isolating everyone) and a strategy where TTI is combined with universal testing (UT; i.e. additional population testing to identify asymptomatic cases). We also model effective coverage of face masks. Results: Increased testing is necessary to suppress the virus after lockdown. Partial reopening accompanied by scaled-up TTI (at 50% test and trace levels), full isolation and moderately effective coverage of masks (30% reduction in overall transmission) can reduce the current resurgence of the virus and protect the economy in the UK. Additional UT from December 2020 reduces the epidemic dramatically by Jan 2021 when combined with enhanced TTI (70% test-trace levels) and full isolation. UT could then be stopped; continued TTI would prevent rapid recurrence. This TTI+UT combination can suppress the virus further to save ~20,000 more lives and avoid ~£90bn economic losses, though costs ~£8bn more to deliver. We assume that all traced and lab-confirmed cases are isolated. The flexible interface we have developed allows exploration of additional scenarios, including different levels of reopening of society after the second lockdown in England as well as different levels of effective mask coverage. Conclusions: Our findings suggest that increased TTI is necessary to suppress the virus and protect the economy after the second lockdown in England. Additional UT from December 2020 reduces the epidemic dramatically by Jan 2021 and could then be stopped, as continued TTI would prevent rapid recurrence.

Impact of enhanced personal protective equipment on the physical and mental well-being of healthcare workers during COVID-19

BACKGROUND

The COVID-19 pandemic has necessitated the use of enhanced personal protective equipment (PPE) in healthcare workers in patient-facing roles. We describe the impact on the physical and mental well-being of healthcare professionals who use enhanced PPE consistently.

METHODS

We conducted a single-centre, cross-sectional study among healthcare professionals who use enhanced PPE. A web-based questionnaire was disseminated to evaluate the effects on individuals' physical and mental well-being. Physical and mental impact was assessed through a visual analogue scale.

RESULTS

Prospective analysis of the views of 72 respondents is reported. 63.9% were women and 36.1% were men. Physical impact included exhaustion, headache, skin changes, breathlessness and a negative impact on vision. Communication difficulties, somnolence, negative impact on overall performance and difficulties in using surgical instrumentation were reported.

CONCLUSION

Our study demonstrates the undeniable negative impact on the front-line healthcare workers using enhanced PPE and lays the ground for larger multicentric assessments given for it to potentially be the norm for the foreseeable future.

A Serious Game Designed to Promote Safe Behaviors Among Health Care Workers During the COVID-19 Pandemic: Development of "Escape COVID-19"

BACKGROUND

As many countries fear and even experience the emergence of a second wave of COVID-19, reminding health care workers (HCWs) and other hospital employees of the critical role they play in preventing SARS-CoV-2 transmission is more important than ever. Building and strengthening the intrinsic motivation of HCWs to apply infection prevention and control (IPC) guidelines to avoid contaminating their colleagues, patients, friends, and relatives is a goal that must be energetically pursued. A high rate of nosocomial infections during the first COVID-19 wave was detected by IPC specialists and further cemented their belief in the need for an engaging intervention that could improve compliance with COVID-19 safe behaviors.

OBJECTIVE

Our aim was to develop a serious game that would promote IPC practices with a specific focus on COVID-19 among HCWs and other hospital employees.

METHODS

The first 3 stages of the SERES framework were used to develop this serious game. A brainswarming session between developers and IPC specialists was used to identify the target audience and acquisition objectives. Nicholson's RECIPE mnemonic (reflection, engagement, choice, information, play, exposition) for meaningful gamification was used to guide the general design. A common and simple terminology was used to suit the broad target audience. The game was tested on various platforms (smartphones, tablets, laptops, desktop computers) by different users during each development loop and before its final release.

RESULTS

The game was designed to target all hospital staff who could be in direct contact with patients within the Geneva University Hospitals. In total, 10 acquisition objectives were defined by IPC specialists and implemented into the game according to the principles of meaningful gamification. A simple storyboard was first created using Microsoft PowerPoint and was progressively refined through multiple iteration loops. Articulate Storyline was then used to create two successive versions of the actual game. In the final version, a unique graphic atmosphere was created with help from a professional graphic designer. Feedback mechanisms were used extensively throughout the game to strengthen key IPC messages.

CONCLUSIONS

The SERES framework was successfully used to create "Escape COVID-19," a serious game designed to promote safe IPC practices among HCWs and other hospital employees during the COVID-19 pandemic. This game can be obtained free of charge for research and educational purposes. A SCORM (shareable content object reference model) package is available to facilitate results and completion tracking on most current learning management systems.

Respiratory Protective Equipment for Healthcare Providers During Coronavirus Pandemic: "Nec Temere, Nec Timide"

In otorhinolaryngology-head and neck surgery, there are several routine and surgical procedures applied to the upper airway that generate droplets and/or aerosols. Therefore, otorhinolaryngology-head and neck surgeons are at higher risk of being exposed to viral content. The COVID-19 pandemic has shaken the world with approximately 30 million affected cases and more than 900.000 deaths officially reported in more than 200 countries/regions from March 11^th, 2020 to date (September 12^th, 2020). All healthcare providers working at the frontlines of the fight against the COVID-19 are at risk of contracting the virus. In this review, we discuss the efficacy of the different types of respiratory protective equipment and remind about the surgery-based respiratory protection strategies in otorhinolaryngology and head and neck surgeries in the light of the latest literature.

SARS-CoV-2: Structure, Biology, and Structure-Based Therapeutics Development

The pandemic of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been posing great threats to the world in many aspects. Effective therapeutic and preventive approaches including drugs and vaccines are still unavailable although they are in development. Comprehensive understandings on the life logic of SARS-CoV-2 and the interaction of the virus with hosts are fundamentally important in the fight against SARS-CoV-2. In this review, we briefly summarized the current advances in SARS-CoV-2 research, including the epidemic situation and epidemiological characteristics of the caused disease COVID-19. We further discussed the biology of SARS-CoV-2, including the origin, evolution, and receptor recognition mechanism of SARS-CoV-2. And particularly, we introduced the protein structures of SARS-CoV-2 and structure-based therapeutics development including antibodies, antiviral compounds, and vaccines, and indicated the limitations and perspectives of SARS-CoV-2 research. We wish the information provided by this review may be helpful to the global battle against SARS-CoV-2 infection.

Impact of an e-learning module on personal protective equipment knowledge in student paramedics: a randomized controlled trial

BACKGROUND

Prehospital professionals such as emergency physicians or paramedics must be able to choose and adequately don and doff personal protective equipment (PPE) in order to avoid COVID-19 infection. Our aim was to evaluate the impact of a gamified e-learning module on adequacy of PPE in student paramedics.

METHODS

This was a web-based, randomized 1:1, parallel-group, triple-blind controlled trial. Student paramedics from three Swiss schools were invited to participate. They were informed they would be presented with both an e-learning module and an abridged version of the current regional prehospital COVID-19 guidelines, albeit not in which order. After a set of 22 questions designed to assess baseline knowledge, the control group was shown the guidelines before answering a set of 14 post-intervention questions. The e-learning group was shown the gamified e-learning module right after the guidelines, and before answering post-intervention questions. The primary outcome was the difference in the percentage of adequate choices of PPE before and after the intervention.

RESULTS

The participation rate was of 71% (98/138). A total of 90 answer sets was analyzed. Adequate choice of PPE increased significantly both in the control (50% [33;83] vs 25% [25;50], P = .013) and in the e-learning group (67% [50;83] vs 25% [25;50], P = .001) following the intervention. Though the median of the difference was higher in the e-learning group, there was no statistically significant superiority over the control (33% [0;58] vs 17% [- 17;42], P = .087). The e-learning module was of greatest benefit in the subgroup of student paramedics who were actively working in an ambulance company (42% [8;58] vs 25% [- 17;42], P = 0.021). There was no significant effect in student paramedics who were not actively working in an ambulance service (0% [- 25;33] vs 17% [- 8;50], P = .584).

CONCLUSIONS

The use of a gamified e-learning module increases the rate of adequate choice of PPE only among student paramedics actively working in an ambulance service. In this subgroup, combining this teaching modality with other interventions might help spare PPE and efficiently protect against COVID-19 infection.

Epidemiological Investigation and Prevention Control Analysis of the Longitudinal Distribution of COVID-19 in Henan Province, China

Epidemic prevention and control in China have entered a new stage of normalization. This article analyzes the epidemiological characteristics of COVID-19 in Henan Province and summarizes the effective disease prevention and control means and measures at the prefecture level; the normalized private data provide a theoretical reference for the formulation and conduct of future prevention and control work. At the same time, these epidemic prevention and control findings can also be used for reference in other countries and regions.

The objective was to analyze the longitudinal distribution, epidemiological characteristics, and local prevention and control measures of coronavirus disease 2019 (COVID-19) in six cities in Henan Province, China, from 21 January 2020 to 17 June 2020: Xinyang City (including Gushi County), Nanyang City (including Dengzhou City), Zhumadian City (including Xincai County), Zhengzhou City (including Gongyi City), Puyang City, and Anyang City (including Hua County). Data were collected and analyzed through the COVID-19 information published on the official websites of the health commissions in the six selected cities of Henan Province. As of 17 June 2020, the cumulative incidence rate of COVID-19 in Henan Province was 1.33/100,000, the cumulative cure rate was 98.27%, the cumulative mortality rate was 1.73%, the age range of diagnosed cases was 5 days to 85 years old, and the male-to-female ratio was 1.09:1. The confirmed cases of COVID-19 in Henan Province were mainly imported cases from Hubei, accounting for 87.74% of all cases, of which the highest proportion was 70.50% in Zhumadian. The contact cases and local cases increased in a fluctuating manner over time. In this paper, epidemiological characteristics of COVID-19 in Henan Province were analyzed from the onset of the outbreak to the effective control within 60 days, and effective and distinctive prevention and control measures in various cities were summarized to provide a favorable useful reference for the further formulation and implementation of epidemic prevention and control and a valuable theoretical basis for effectively avoiding a second outbreak.

IMPORTANCE Epidemic prevention and control in China have entered a new stage of normalization. This article analyzes the epidemiological characteristics of COVID-19 in Henan Province and summarizes the effective disease prevention and control means and measures at the prefecture level; the normalized private data provide a theoretical reference for the formulation and conduct of future prevention and control work. At the same time, these epidemic prevention and control findings can also be used for reference in other countries and regions.

AAID White Paper: Management of the Dental Implant Patient During the COVID-19 Pandemic and Beyond

The scientific community's understanding of how the SARS-CoV-2 virus is transmitted and how to best mitigate its spread is improving daily. To help protect patients from acquiring COVID-19 from a dental office nosocomial infection, many state or local governments have classified dental treatments as "nonessential" and have paused routine dental care. Dentists have been instructed to perform only procedures designated as emergencies. Unfortunately, there is not a good understanding of what a dental emergency is among governmental leaders. What a government agency may perceive as an elective procedure may be seen as "essential" by the dental clinician responsible for maintaining the oral health of the patient. Each dental specialty understands the effects delayed care has on a patient's oral and systemic health. Dentistry has made extensive progress in improving oral health through prevention of the dental emergency. The dental profession must work together to prevent the reversal of the progress dentistry and patients have made. This American Academy of Implant Dentistry (AAID) White Paper discusses what COVID-19 is and how it impacts dental treatments, presents guidelines for dentistry in general and for dental implant related treatments, specifically. Recommendations for implant dentistry include the following: (1) what constitutes a dental implant related emergency, (2) how patients should be screened and triaged, (3) what personal protective equipment is necessary, (4) how operatories should be equipped, (5) what equipment should be used, and (6) what, when, and how procedures can be performed. This paper is intended to provide guidance for the dental implant practice so patients and dental health care providers can be safe, and offices can remain open and viable during the pandemic.