Asymptomatic Transmission and the Infection Fatality Risk for COVID-19: Implications for School Reopening

Child and adolescent COVID-19 vaccination coverage by educational setting, United States

OBJECTIVES

The COVID-19 pandemic changed the setting of education for many children in the U.S. Understanding COVID-19 vaccination coverage by educational setting is important for developing targeted messages, increasing parents' confidence in COVID-19 vaccines, and protecting all children from severe effects of COVID-19 infection.

STUDY DESIGN/METHODS

Using data from the Household Pulse Survey (n = 25,173) collected from December 9-19, 2022, January 4-16, 2023, and February 1-13, 2023, this study assessed factors associated with COVID-19 vaccination and reasons for non-vaccination among school-aged children 5-11 and adolescents 12-17 by educational setting.

RESULTS

Among children 5-11 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (53.7%) compared to those who were homeschooled (32.5%). Furthermore, among adolescents 12-17 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (73.5%) or virtual/online instruction (70.1%) compared to those who were homeschooled (51.0%). Children and adolescents were more likely to be vaccinated if the parental respondent had been vaccinated compared to those who had not. Among children and adolescents who were homeschooled, main reasons for non-vaccination were concern about side effects (45.4-51.6%), lack of trust in COVID-19 vaccines (45.0-50.9%), and lack of trust in the government (32.7-39.2%).

CONCLUSIONS

Children and adolescents who were home-schooled during the pandemic had lower vaccination coverage than those who attended school in person, and adolescents who were home-schooled had lower vaccination coverage than those who received virtual instruction. Based on the reasons for non-vaccination identified in this study, increasing parental confidence in vaccines, and reducing barriers to access are important for supporting COVID-19 vaccination for school-age children.

Seroprevalence of antibodies against SARS-CoV-2 in the school community in Campo Grande, state of Mato Grosso do Sul, Brazil, October 2021-November 2022

Introduction

With the reopening of schools during the coronavirus disease 2019 (COVID-19) pandemic, it was imperative to understand the role of students and education professionals in the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this paper, we determined the seroprevalence of the SARS-CoV-2 anti-nucleocapsid antibodies in the school community in Campo Grande, the capital and most populous city of the state of Mato Grosso do Sul (Brazil) and evaluated its association with sex, school level, and school type.

Materials and methods

The survey was carried out in 20 public and private schools in the urban region of Campo Grande using the TR DPP® COVID-19 immunoglobulin M/immunoglobulin G (IgM/IgG) kit from the Immunobiological Technology Institute (Bio-Manguinhos, Rio de Janeiro, Brazil). Testing was carried out in three periods: from October to December 2021; from March to July 2022; and from August to November 2022. The participants were students aged 6-17 years enrolled in primary or secondary schools and professionals of different ages and roles.

Results

During the first testing period, 162 participants were seropositive for the IgM and/or IgG anti-nucleocapsid SARS-CoV-2 antibodies, with an estimated seroprevalence of 19.6% using Bayesian multilevel regression. In the second period, 251 participants were seropositive (estimated seroprevalence, 34.6%), while in the third period, 393 participants were seroconverted (estimated seroprevalence, 56.7%). In 2022, there was an increase in the seroconversion rate compared to that in 2021. The most frequently described acute manifestations in the three periods were fever, headache, sore throat, and runny nose. In terms of the demographic profile, there was no predominance of seropositivity between the sexes, although women represented approximately 70% of the study population. There were also no differences between students and school staff.

Discussion

The results made it possible to evaluate the extent of SARS-CoV-2 transmission in the school community through immunity developed against the virus, in addition to providing information about COVID-19 symptoms in children, adolescents, and adults.

Knowledge, psychological impacts, and protective behaviours during the first wave of the COVID-19 pandemic among Chinese residents in Canada with dependent school-age children: a cross-sectional online study

BACKGROUND

The purpose of this study was to describe the knowledge, protective behaviours, and psychological impact of COVID-19 on Chinese residents in Canada, as the emotional and behavioural impacts of the pandemic have not been intensively studied amongst these populations. It was important to determine whether having dependent school-age children (DSAC) aged 16 or under was associated with adverse psychological impacts amongst the Chinese residents living in the country.

METHODS

In April 2020, 757 eligible participants were recruited through a snowball sampling to complete an online survey related to the COVID-19 pandemic. Psychological, behavioural, and sociodemographic variables were collected and first analyzed using descriptive and univariate statistics. Multiple logistic regression analyses were performed to further confirm the observed significant associations in bivariate analyses for selected psychological outcome variables.

RESULTS

Seven hundred forty-two participants who responded to the "dependent school-age children" question were included in the analysis. Most of them identified as females (65.8%) and 77.2% included receiving a university degree or higher. There were no significant differences in COVID-19 knowledge between those living with or without DSAC. However, participants with DSAC were more likely to perceive themselves as being at greater risk of contracting COVID-19 (p = .023); therefore, having a higher chance of adopting protective behaviours (e.g., hand washing, sanitizing frequently or disinfecting work and living spaces (p < .05), elevated risks of depression (p = .007), and stress (p = .010), compared to those without DSAC.

CONCLUSIONS

Predominantly, the Chinese residents in Canada with dependent school-age children were more likely to report the negative psychological impacts of the pandemic. These findings warrant further investigations that may contribute to informing key stakeholders about the identification and implementation of policies and interventions to support the needs of parents with young children, during and after the pandemic.

Thematic analysis of national online narratives on regular asymptomatic testing for Covid-19 in schools in England

OBJECTIVE

To understand the public perceptions of the schools Covid-19 testing programme in England.

DESIGN

Qualitative social media analysis.

SETTING

Online users of parenting forums (Mumsnet and Netmums), Facebook newspaper pages and Daily Mail online readers, who responded to posts or articles about the schools testing programme in England, between 1 and 31 March, 2021.

RESULTS

Overall, seven main themes were identified, these were divided into barriers and facilitators to engaging in testing for Covid-19. Barriers were: uncertainty around testing in the absence of symptoms; concerns about testing; implications about testing positive; mistrust in the Government. Facilitators were: desire to protect others; desire to return to normality; and hearing others' positive experiences.

CONCLUSIONS

Our analysis highlighted that alongside well-established barriers to engaging in asymptomatic testing, parents were having to negotiate additional complex decisions around balancing their child's anxiety over testing alongside acknowledgement of the implications of regular testing, such as return to normality and protecting others. Parents and children would benefit from additional practical and social support to facilitate engagement with the schools testing programme.

Implementation of a Hardware-Assisted Bluetooth-Based COVID-19 Tracking Device in a High School: Mixed Methods Study

BACKGROUND

Contact tracing is a vital public health tool used to prevent the spread of infectious diseases. However, traditional interview-format contact tracing (TCT) is labor-intensive and time-consuming and may be unsustainable for large-scale pandemics such as COVID-19.

OBJECTIVE

In this study, we aimed to address the limitations of TCT. The Yale School of Engineering developed a Hardware-Assisted Bluetooth-based Infection Tracking (HABIT) device. Following the successful implementation of HABIT in a university setting, this study sought to evaluate the performance and implementation of HABIT in a high school setting using an embedded mixed methods design.

METHODS

In this pilot implementation study, we first assessed the performance of HABIT using mock case simulations in which we compared contact tracing data collected from mock case interviews (TCT) versus Bluetooth devices (HABIT). For each method, we compared the number of close contacts identified and identification of unique contacts. We then conducted an embedded mixed methods evaluation of the implementation outcomes of HABIT devices using pre- and postimplementation quantitative surveys and qualitative focus group discussions with users and implementers according to the Reach, Effectiveness, Adoption, Implementation, and Maintenance framework.

RESULTS

In total, 17 students and staff completed mock case simulations in which 161 close contact interactions were detected by interview or Bluetooth devices. We detected significant differences in the number of close contacts detected by interview versus Bluetooth devices (P<.001), with most (127/161, 78.9%) contacts being reported by interview only. However, a significant number (26/161, 16.1%; P<.001) of contacts were uniquely identified by Bluetooth devices. The interface, ease of use, coherence, and appropriateness were highly rated by both faculty and students. HABIT provided emotional security to users. However, the prototype design and technical difficulties presented barriers to the uptake and sustained use of HABIT.

CONCLUSIONS

Implementation of HABIT in a high school was impeded by technical difficulties leading to decreased engagement and adherence. Nonetheless, HABIT identified a significant number of unique contacts not reported by interview, indicating that electronic technologies may augment traditional contact tracing once user preferences are accommodated and technical glitches are overcome. Participants indicated a high degree of acceptance, citing emotional reassurance and a sense of security with the device.

Predictors of COVID-19 Vaccine Uptake in Teachers: An On-line Survey in Greece

COVID-19 vaccines are safe at a very high rate and protect against severe disease, hospitalization, and mortality. Schools are workplaces with high transmissibility of coronavirus and teachers are at risk of infection. The study aimed to find out the predictors of COVID-19 vaccine uptake in teachers. An on-line cross-sectional survey with a convenience sample was conducted, in Greece, during December 2021. We collected demographic data of teachers and we measured their attitudes towards COVID-19 vaccination and the pandemic. The sample included 513 teachers. The majority of them was vaccinated against COVID-19 (85.8%). The most important reasons for teachers' decline in COVID-19 vaccination were their concerns about safety, effectiveness and the side effects of COVID-19 vaccine. Also, furthermore they were characterized by strong self-assessment that they will not be infected by the COVID-19, and self-assessment that the COVID-19 vaccination will be useless for those who have already been diagnosed with COVID-19. After multivariable analysis, we found that increased age (OR 1.08, 95% CI 1.02-1.14, p = 0.011), and trust in COVID-19 vaccination (OR 2.57, 95% CI 2.07-3.18, p < 0.001) were related with an increased probability of a COVID-19 vaccine uptake. Also, teachers who lived with elderly people or vulnerable groups (OR 4.81, 95% CI 1.55-14.89, p = 0.006) during the COVID-19 pandemic, demonstrated greater probability to take COVID-19 vaccine. The study highlighted the need for reliable and accurate public information on both the risks of coronavirus infection and the vaccines' safety and efficacy.

Factors Influencing Parent and Guardian Decisions on Vaccinating Their Children Against SARS-CoV-2: A Qualitative Study

This qualitative analysis sought to explore factors that influenced parent/guardian intentions to vaccinate their children against SARS-CoV-2 in San Francisco, California, USA in order to inform San Francisco Department of Public Health's (SFDPH) youth vaccine rollout program. 30-minute, semi-structured telephone interviews were conducted with parents and guardians in either Spanish or English. Respondents shared their perspectives on vaccinating their children against SARS-CoV-2. Interviews were conducted over the telephone and recorded on Zoom. Participants (n = 40) were parents/guardians responding on behalf of their adolescent children (age 13+) and parents/guardians identified from the SFDPH COVID-19 testing database who tested for SARS-CoV-2 within the last 2 weeks. Interviews were conducted, audio recorded, transcribed, translated into English as appropriate, and rapidly analyzed in REDCap according to matrix analysis methodology to develop parent study themes. Perspectives on child vaccination were then explored through thematic analysis. Three themes were identified from the thematic analysis: (1) parental desires for children to return to school safely, (2) unclear messaging and information on COVID-19 prevention and vaccination, and (3) consideration of child's desires or opinions on receiving the vaccine. This study highlights specific factors influencing parent/guardian decisions on whether to vaccinate their children against SARS-CoV-2. The analysis also illustrates a potential role for children to play in influencing household vaccine decision-making.

Narrative Review of the COVID-19 Pandemic's First Two Years in Italy

Italy was the first country in the western world to be affected by the COVID-19 pandemic, arguably among the worst-affected ones, counting 12 million cases and 150 thousand deaths two years since the first case. Facing new challenges, Italy has enacted different strategies and policies to limit the spread of the SARS-CoV-2 virus and treat those affected by COVID-19. This narrative review provided an overview of factors, measures, and actions that shaped Italy's first two years of the COVID-19 pandemic by investigating epidemiological data and using a mixed-method approach. This narrative review aimed to summarize the most relevant aspects and measures and analyze available data to provide policymakers and healthcare providers with the instruments to learn from this pandemic and improve their preparedness for future pandemic events. The first two years of the pandemic differ in that, during the first year, significant necessary changes to the way health systems were organized were implemented, increasing healthcare spending and adopting social and physical distancing measures that were stricter than the ones adopted in the second year. However, as the pandemic progressed, increased knowledge of the virus and related variants, as well as the introduction of highly effective vaccines, which were not equally available to the whole population, resulted in a stratification of COVID-19 infections and deaths based on factors such as age, vaccination status, and individual susceptibility to the virus.

Data-driven contact network models of COVID-19 reveal trade-offs between costs and infections for optimal local containment policies

While several non-pharmacological measures have been implemented for a few months in an effort to slow the coronavirus disease (COVID-19) pandemic in the United States, the disease remains a danger in a number of counties as restrictions are lifted to revive the economy. Making a trade-off between economic recovery and infection control is a major challenge confronting many hard-hit counties. Understanding the transmission process and quantifying the costs of local policies are essential to the task of tackling this challenge. Here, we investigate the dynamic contact patterns of the populations from anonymized, geo-localized mobility data and census and demographic data to create data-driven, agent-based contact networks. We then simulate the epidemic spread with a time-varying contagion model in ten large metropolitan counties in the United States and evaluate a combination of mobility reduction, mask use, and reopening policies. We find that our model captures the spatial-temporal and heterogeneous case trajectory within various counties based on dynamic population behaviors. Our results show that a decision-making tool that considers both economic cost and infection outcomes of policies can be informative in making decisions of local containment strategies for optimal balancing of economic slowdown and virus spread.

Mixed-methods process evaluation of a residence-based SARS-CoV-2 testing participation pilot on a UK university campus during the COVID-19 pandemic

BACKGROUND

Regular testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is an important strategy for controlling virus outbreaks on university campuses during the COVID-19 pandemic but testing participation rates can be low. The Residence-Based Testing Participation Pilot (RB-TPP) was a novel intervention implemented at two student residences on a large UK university campus over 4 weeks. The aim of the pilot was to increase the frequency of asymptomatic SARS-CoV-2 saliva testing onsite. This process evaluation aimed to determine whether RB-TPP was implemented as planned and identify implementation barriers and facilitators.

METHODS

A mixed-methods process evaluation was conducted alongside the RB-TPP. Evaluation participants were students (opting in, or out of RB-TPP) and staff with a role in service provision or student support. Monitoring data were collected from the intervention delivery team and meeting records. Data were collected from students via online survey (n = 152) and seven focus groups (n = 30), and from staff via individual interviews (n = 13). Quantitative data were analysed descriptively and qualitative data thematically. Barriers and facilitators to implementation were mapped to the 'Capability, Opportunity, Motivation-Behaviour' (COM-B) behaviour change framework.

RESULTS

Four hundred sixty-four students opted to participate in RB-TPP (98% of students living onsite). RB-TPP was implemented broadly as planned but relaxed social distancing was terminated early due to concerns relating to national escalation of the COVID-19 Delta variant, albeit testing continued. Most students (97.9%) perceived the period of relaxed social distancing within residences positively. The majority engaged in asymptomatic testing (88%); 46% (52% of testers) were fully compliant with pre-determined testing frequency. Implementation was facilitated by convenience and efficiency of testing, and reduction in the negative impacts of isolation through opportunities for students to socialise. Main barriers to implementation were perceived mixed-messages about the rules, ambivalent attitudes, and lack of adherence to COVID-19 protective measures in the minority.

CONCLUSIONS

This process evaluation identifies factors that help or hinder the success of university residence-based outbreak prevention and management strategies. RB-TPP led to increased rates of SARS-CoV-2 testing participation among students in university residences. Perceived normalisation of university life significantly enhanced student mental wellbeing. The complexity and challenge generated by multiple lines of communication and rapid adaptions to a changing pandemic context was evident.

TRIAL REGISTRATION NUMBER

UKAS 307727-02-01; Pre-results.

CLINICALTRIALS

gov Identifier: NCT05045989 ; post-results (first posted, 16/09/21).

ETHICAL APPROVAL

Faculty of Medicine & Health Sciences Research Ethics Committee, University of Nottingham (Ref: FMHS 96-0920).

The impact of school closure intervention during the third wave of the COVID-19 pandemic in Italy: Evidence from the Milan area

Background

In February 2021, the spread of a new variant of SARS-CoV-2 in the Lombardy Region, Italy caused concerns about school-aged children as a source of contagion, leading local authorities to adopt an extraordinary school closure measure. This generated a debate about the usefulness of such an intervention in light of the trade-off between its related benefits and costs (e.g. delays in educational attainment, impact on children and families’ psycho-physical well-being). This article analyses the epidemiological impact of the school closure intervention in the Milan metropolitan area.

Methods

Data from the Agency for Health Protection of the Metropolitan City of Milan allowed analysing the trend of contagion in different age classes before and after the intervention, adopting an interrupted times series design, providing a quasi-experimental counterfactual scenario. Segmented Poisson regression models of daily incident cases were performed separately for the 3–11-year-old, the 12–19-year-old, and the 20+-year-old age groups, examining the change in the contagion curves after the intervention, adjusting for time-varying confounders. Kaplan-Meier survival curves and Cox regression were used to assess the equality of survival curves in the three age groups before and after the intervention.

Results

Net of time-varying confounders, the intervention produced a daily reduction of the risk of contagion by 4% in those aged 3–11 and 12–19 (IRR = 0·96) and by 3% in those aged 20 or more (IRR = 0·97). More importantly, there were differences in the temporal order of contagion decrease between the age groups, with the epidemic curve lowering first in the school-aged children directly affected by the intervention, and only subsequently in the adult population, which presumably indirectly benefitted from the reduction of contagion among children.

Conclusion

Though it was not possible to completely discern the effect of school closures from concurrent policy measures, a substantial decrease in the contagion curves was clearly detected after the intervention. The extent to which the slowdown of infections counterbalanced the social costs of the policy remains unclear.

Percentage of Asymptomatic Infections among SARS-CoV-2 Omicron Variant-Positive Individuals: A Systematic Review and Meta-Analysis

Background: Asymptomatic infections are potential sources of transmission for coronavirus disease 2019, especially during the epidemic of the SARS-CoV-2 Omicron variant. We aimed to assess the percentage of asymptomatic infections among SARS-CoV-2 Omicron variant-positive individuals detected by gene sequencing or specific polymerase chain reaction (PCR). Methods: We searched PubMed, EMBASE, and Web of Science from 26 November 2021 to 13 April 2022. This meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered with PROSPERO (CRD42022327894). Three researchers independently extracted data and two researchers assessed quality using pre-specified criteria. The pooled percentage with 95% confidence interval (CI) of asymptomatic infections of SARS-CoV-2 Omicron was estimated using random-effects models. Results: Our meta-analysis included eight eligible studies, covering 7640 Omicron variant-positive individuals with 2190 asymptomatic infections. The pooled percentage of asymptomatic infections was 32.40% (95% CI: 25.30−39.51%) among SARS-CoV-2 Omicron variant-positive individuals, which was higher in the population in developing countries (38.93%; 95% CI: 19.75−58.11%), with vaccine coverage ≥ 80% (35.93%; 95% CI: 25.36−46.51%), with a travel history (40.05%; 95% CI: 7.59−72.51%), community infection (37.97%; 95% CI: 10.07−65.87%), and with a median age < 20 years (43.75%; 95% CI: 38.45−49.05%). Conclusion: In this systematic review and meta-analysis, the pooled percentage of asymptomatic infections was 32.40% among SARS-CoV-2 Omicron variant-positive individuals. The people who were vaccinated, young (median age < 20 years), had a travel history, and were infected outside of a clinical setting (community infection) had higher percentages of asymptomatic infections. Screening is required to prevent clustered epidemics or sustained community transmission caused by asymptomatic infections of Omicron variants, especially for countries and regions that have successfully controlled SARS-CoV-2.

Serology as a Tool to Assess Infectious Disease Landscapes and Guide Public Health Policy

Understanding the local burden and epidemiology of infectious diseases is crucial to guide public health policy and prioritize interventions. Typically, infectious disease surveillance relies on capturing clinical cases within a healthcare system, classifying cases by etiology and enumerating cases over a period of time. Disease burden is often then extrapolated to the general population. Serology (i.e., examining serum for the presence of pathogen-specific antibodies) has long been used to inform about individuals past exposure and immunity to specific pathogens. However, it has been underutilized as a tool to evaluate the infectious disease burden landscape at the population level and guide public health decisions. In this review, we outline how serology provides a powerful tool to complement case-based surveillance for determining disease burden and epidemiology of infectious diseases, highlighting its benefits and limitations. We describe the current serology-based technologies and illustrate their use with examples from both the pre- and post- COVID-19-pandemic context. In particular, we review the challenges to and opportunities in implementing serological surveillance in low- and middle-income countries (LMICs), which bear the brunt of the global infectious disease burden. Finally, we discuss the relevance of serology data for public health decision-making and describe scenarios in which this data could be used, either independently or in conjunction with case-based surveillance. We conclude that public health systems would greatly benefit from the inclusion of serology to supplement and strengthen existing case-based infectious disease surveillance strategies.

Perspectives and Factors Affecting the Preventive Behavior Pertinent to COVID-19 among School Employees in Chiang Mai, Thailand: A Cross-Sectional Study

The school is one of the most challenging environments for management to prevent the spread of COVID-19 infection. School employees play important roles as the main practitioners of recommended preventive measures. Consistent application of preventive measures by school employees strengthens the school’s readiness to reopen for on-site education. The study objectives are (1) to assess school employee agreement and actions in accordance with the preventive measures and recommendations for COVID-19 prevention and control, (2) to assess the readiness of the school and employees for on-site education, and (3) to determine factors associated with consistent performance of these measures. A cross-sectional study was conducted via an online survey from 5 November 2021 to 25 January 2022. Self-reported online questionnaires were used to collect school employees’ data. The readiness of schools for on-site education was assessed using 44 indicators from the practical guidelines by the Thai Department of Health. Of the 402 study participants, the majority of participants had agreed to all measures and recommendations for COVID-19 prevention and control in school. High levels of concern and disagreement in school re-opening (aOR 3.78, 95%CI 1.04 to 13.70; p = 0.043) were associated with higher consistent performance of the measures and recommendations for COVID-19 prevention and control in schools. Male teachers (aOR 0.43, 95%CI 0.23 to 0.80; p = 0.008) and any disagreement with these measures and recommendations (aOR 0.03, 95%CI 0.01 to 0.23; p < 0.001) were associated with lower consistent performance. Our study findings can inform the stakeholders to decide on the re-opening and supportive strategies. School employees, especially in male employees, must be supported from the relevant sectors to decrease disagreement to the measures and enhance awareness of the pandemic situation before the school re-opening.

The impact of impulsivity and school attendance on COVID-19 spread: A web-based cross-sectional questionnaire

Some personal and social decisions can be influential in the spread of COVID-19. There are no studies examining school attendance, impulsivity, COVID-19 phobia, and psychological resilience together while the effect of some individual and social measures on COVID-19 has been frequently investigated. In this study 360 participants were evaluated through an online questionnaire method during the peak of the COVID-19 pandemic. Sociodemographic data form prepared by the researchers, COVID-19 Phobia Scale, Barratt Impulsivity Scale, and Brief Resilience Scale were used in the study. In all, 20.6% (n = 74) of participants had previously experienced COVID-19. The rate of individuals who experienced the death of any of their relatives due to COVID-19 was 17.8%. Only 65.8% of respondents fully complied with government-implemented measures for the outbreak. School attendance (OR = 1.983, p = .033) and impulsivity (OR = 1.115, p < .001) were found to be positively correlated with COVID-19. The presence of a significantly higher psychiatric disease admission history in patients with COVID-19 in binary comparisons did not reach the level of significance in regression analysis. Our results suggest that high school attendance and impulsivity scores are positively correlated with COVID-19 in young people. Government strategies related to schools need to be carefully reviewed for this reason.

COVID-19 Vaccine Hesitancy among Adolescents: Cross-Sectional School Survey in Four Chinese Cities Prior to Vaccine Availability

To address the novel coronavirus disease (COVID-19) pandemic, development and regulatory evaluations have been accelerated for vaccines, authorizing emergency use. To anticipate vaccine preparedness in adolescents, we studied COVID-19 vaccination awareness and willingness to vaccinate before the vaccine became available. We conducted a cross-sectional survey among 9153 (4575 boys, 50%) students with a mean age of 14.2 years old in four cities in China to collect information on demographic characteristics and their COVID-19 vaccination concerns. Multinomial logistic regression was used to analyze the influencing factors of vaccine hesitancy (“not sure”) and resistance (“do not want it”). The results showed that 2891 (31.6%) were hesitant and 765 (8.4%) were resistant to being vaccinated. Additionally, multivariable analyses showed that vaccine hesitancy and vaccine resistance were associated with living in the Beijing area (OR = 1.62; 95% CI: 1.40–1.88; OR = 1.81; 95% CI: 1.44–2.28), lack of influenza vaccination experience (OR = 1.33; 95% CI: 1.14–1.55; OR = 1.57; 95% CI: 1.25–1.98), no perceived susceptibility (OR = 1.72; 95% CI: 1.50–1.97; OR = 3.57; 95% CI: 2.86–4.46), and perceiving no cues to action (OR = 3.24; 95% CI: 2.56–4.11; OR = 27.68; 95% CI: 21.81–35.13). Postulating a highly effective vaccine (OR = 0.84; 95% CI: 0.72–0.98; OR = 0.66; 95% CI: 0.52–0.83) decreased both vaccine hesitancy and resistance. Vaccine hesitancy alone was associated with girls (OR = 1.21; 95% CI: 1.09–1.36) and was less common among students boarding at school (OR = 0.79; 95% CI: 0.68–0.92), postulating convenient vaccine access (OR = 0.84; 95% CI: 0.73–0.96), and having doctors’ recommendation (OR = 0.86; 95% CI: 0.76–0.98). In conclusion, the results of the study showed that vaccine hesitancy among students in China was associated with limited health literacy and lower risk awareness. Our findings in China suggest that educating youth regarding COVID-19 and the safety and effectiveness of immunization help reduce concerns and increase vaccine confidence and acceptance.

An exploration of the political, social, economic and cultural factors affecting how different global regions initially reacted to the COVID-19 pandemic

Responses to the early (February–July 2020) COVID-19 pandemic varied widely, globally. Reasons for this are multiple but likely relate to the healthcare and financial resources then available, and the degree of trust in, and economic support provided by, national governments. Cultural factors also affected how different populations reacted to the various pandemic restrictions, like masking, social distancing and self-isolation or self-quarantine. The degree of compliance with these measures depended on how much individuals valued their needs and liberties over those of their society. Thus, several themes may be relevant when comparing pandemic responses across different regions. East and Southeast Asian populations tended to be more collectivist and self-sacrificing, responding quickly to early signs of the pandemic and readily complied with most restrictions to control its spread. Australasian, Eastern European, Scandinavian, some Middle Eastern, African and South American countries also responded promptly by imposing restrictions of varying severity, due to concerns for their wider society, including for some, the fragility of their healthcare systems. Western European and North American countries, with well-resourced healthcare systems, initially reacted more slowly, partly in an effort to maintain their economies but also to delay imposing pandemic restrictions that limited the personal freedoms of their citizens.

School closures and reopenings during the COVID-19 pandemic: a scoping review protocol

OBJECTIVE

The objective of this scoping review is to provide an overview of existing studies and evidence on the impact of school closures and reopenings during the pandemic.

INTRODUCTION

The COVID-19 pandemic has necessitated widespread school closures, and reopening schools safely has a pivotal role in the well-being of children and teachers, SARS-CoV-2 transmission control and optimal societal functioning. Widespread school closures in response to the COVID-19 pandemic have caused adverse effects on the education, physical health and mental well-being of children. An understanding of the impact of school closures and reopenings as well as factors influencing school safety is critical to bringing schools' operational status back to normal. Despite the implication of individual concerns and knowledge on disease prevention practices, there is a paucity of research on individual knowledge, needs and behaviours in the context of school reopenings. In the proposed study, we will conduct a scoping review to identify and provide inventory of the current research and evidence on the impact of COVID-19 on K-12 schools (primary and secondary schools) and vice versa.

METHODS AND ANALYSIS

Eligible studies/literature include members of K-12 (primary and secondary) schools (students, parents, staff, faculty, COVID-19 coordinator, school nurses) in countries affected by the COVID-19 pandemic. We will exclude university or college students. There will be no exclusion based on methods, timing or school operational status.All concepts regarding school closures and reopenings will be considered, and all types of research will be considered.This scoping review will follow the Joanna Briggs Institute methodology for scoping reviews. Sources of evidence published from 2020 to 31 October 2021 will be included. The search will include PubMed, preprints in EuropePMC, ERIC, Scopus, Web of Science Core Collection, PsycINFO, Embase, CINAHL and VHL. We will cover grey literature in Harvard Think Tank Database, COVID-19 Evidence Hub like COVID-END and Google Scholar. The abstract and title screening, full-text screening and data extraction will be done by two independent reviewers.Disagreements will be resolved by an independent third reviewer. Data extract will be done on Qualtrics form to ensure accurate extraction. Citation chaining will be performed on key articles identified. A critical appraisal will be performed.The scoping review will take place from 1 August 2021 to 15 November 2021. We will perform a final round of updated search and citation chaining.

ETHICS AND DISSEMINATION

The review will be based on published works and grey literature, thus it is exempt from formal ethical approval. This protocol cannot be registered in the Prospective Register of Systematic Reviews because this registry is not for scoping reviews. We will register it in OSF Registration. The paper will appear in a peer-reviewed, open-access journal to ensure a broad dissemination.

Private High School Reopened-COVID Mitigation and Clinical Surveillance Using an Internet Application

CONTEXT

Recommendations for COVID-safe, in-person, high school education have included masks and distancing between students but do not describe a scalable surveillance solution to rapidly identify and mitigate disease prevalence or exposure.

METHODS

Through an Internet application, all school participants reported symptoms, illness, or exposure daily. Physician-supervised follow-up interviews were reviewed and recorded in daily rounds. Students and faculty were allowed or prohibited to enter school based on the results.

RESULTS

From August 30, 2020, until April 13, 2021, a high school in Bergen County, New Jersey (an epicenter of high COVID prevalence), with 889 students and 214 faculty members, staff, and volunteers, generated 1497 assessments. Reasons for initial evaluation included 48 (3%) participants with positive COVID tests, 520 (34%) COVID-exposed, 178 (12%) exposed to someone with symptoms and unknown COVID status, 208 (14%) subjects with symptoms themselves, 525 (35%) exposed to a high-risk geography or air travel, and 12 (1%) contacts of a contact. Of the 61 subjects ultimately diagnosed with COVID, the sources of infection were 36 (57%) home exposure, 16 (27%) confirmed nonschool sources, 8 (13%) unknown, 1 (2%) travel to a high-risk area, and only one potential case of in-school transmission.

CONCLUSIONS

Masks, distance, and aggressive contact tracing supported by an Internet application with consistent application of quarantine protocols successfully permitted in-school education without COVID spread in a high prevalence environment. This finding remains important to guide safety measures should vaccine-resistant strains-or new pandemics-challenge us in the future.

COVID-19 Vaccine-Related Thrombosis: A Systematic Review and Exploratory Analysis

Introduction

The World Health Organization declared the coronavirus disease 2019 (COVID-19) pandemic on March 11, 2020. Two vaccine types were developed using two different technologies: viral vectors and mRNA. Thrombosis is one of the most severe and atypical adverse effects of vaccines. This study aimed to analyze published cases of thrombosis after COVID-19 vaccinations to identify patients' features, potential pathophysiological mechanisms, timing of appearance of the adverse events, and other critical issues.

Materials and Methods

We performed a systematic electronic search of scientific articles regarding COVID-19 vaccine-related thrombosis and its complications on the PubMed (MEDLINE) database and through manual searches. We selected 10 out of 50 articles from February 1 to May 5, 2021 and performed a descriptive analysis of the adverse events caused by the mRNA-based Pfizer and Moderna vaccines and the adenovirus-based AstraZeneca vaccine.

Results

In the articles on the Pfizer and Moderna vaccines, the sample consisted of three male patients with age heterogeneity. The time from vaccination to admission was ≤3 days in all cases; all patients presented signs of petechiae/purpura at admission, with a low platelet count. In the studies on the AstraZeneca vaccine, the sample consisted of 58 individuals with a high age heterogeneity and a high female prevalence. Symptoms appeared around the ninth day, and headache was the most common symptom. The platelet count was below the lower limit of the normal range. All patients except one were positive for PF4 antibodies. The cerebral venous sinus was the most affected site. Death was the most prevalent outcome in all studies, except for one study in which most of the patients remained alive.

Discussion

Vaccine-induced thrombotic thrombocytopenia (VITT) is an unknown nosological phenomenon secondary to inoculation with the COVID-19 vaccine. Several hypotheses have been formulated regarding its physiopathological mechanism. Recent studies have assumed a mechanism that is assimilable to heparin-induced thrombocytopenia, with protagonist antibodies against the PF4-polyanion complex. Viral DNA has a negative charge and can bind to PF4, causing VITT. New experimental studies have assumed that thrombosis is related to a soluble adenoviral protein spike variant, originating from splicing events, which cause important endothelial inflammatory events, and binding to endothelial cells expressing ACE2.

Conclusion

Further studies are needed to better identify VITT's pathophysiological mechanisms and genetic, demographic, or clinical predisposition of high-risk patients, to investigate the correlation of VITT with the different vaccine types, and to test the significance of the findings.

Model-based assessment of SARS-CoV-2 Delta variant transmission dynamics within partially vaccinated K-12 school populations

BACKGROUND

We examined school reopening policies amidst ongoing transmission of the highly transmissible Delta variant, accounting for vaccination among individuals ≥12 years.

METHODS

We collected data on social contacts among school-aged children in the California Bay Area and developed an individual-based transmission model to simulate transmission of the Delta variant of SARS-CoV-2 in schools. We evaluated the additional infections in students and teachers/staff resulting over a 128-day semester from in-school instruction compared to remote instruction when various NPIs (mask use, cohorts, and weekly testing of students/teachers) were implemented, across various community-wide vaccination coverages (50%, 60%, 70%), and student (≥12 years) and teacher/staff vaccination coverages (50% - 95%).

FINDINGS

At 70% vaccination coverage, universal masking reduced infections by >57% among students. Masking plus 70% vaccination coverage enabled achievement of <50 excess cases per 1,000 students/teachers, but stricter risk tolerances, such as <25 excess infections per 1,000 students/teachers, required a cohort approach in elementary and middle school populations. In the absence of NPIs, increasing the vaccination coverage of community members from 50% to 70% or elementary teachers from 70% to 95% reduced the excess rate of infection among elementary school students attributable to school transmission by 24% and 37%, respectively.

INTERPRETATIONS

Amidst Delta variant circulation, we found that schools are not inherently low risk, yet can be made so with high community vaccination coverages and masking. Vaccination of adults protects unvaccinated children.

FUNDING

National Science Foundation grant no. 2032210; National Institutes of Health grant nos. R01AI125842 and R01AI148336; MIDAS Coordination Center (MIDASSUP2020-4).

Progress in the Diagnosis and Treatment of COVID-19 in Children: A Review

Coronavirus disease 2019 (COVID-19) has been circulating in many countries around the world, characterized by long incubation period, strong infectivity, strong variability, high population susceptibility and diversified transmission methods. Its causative agent is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Compared with adult patients, the clinical manifestations of COVID-19 in children are often dominated by mild or asymptomatic infections, but children are also important virus carriers and play an important role in the transmission of the virus. In addition, some children will show excessive inflammatory response and experience serious complications such as multisystem inflammatory syndrome in children (MIS-C). At present, the research on COVID-19 in children is still imperfect. This article will review epidemiological characteristics, the mechanism of action, variant characteristics, clinical manifestations, auxiliary examinations and treatment of children with COVID-19, in order to provide help for the diagnosis, treatment and research of children with COVID-19.

Room HVAC Influences on the Removal of Airborne Particulate Matter: Implications for School Reopening during the COVID-19 Pandemic

(1) Background: Many schools and higher education settings have confronted the issue of reopening their facilities after the COVID-19 pandemic. In response, several airflow strategies spanning from adding portable air purifiers to major mechanical overhauls have been suggested to equip classrooms with what is necessary to provide a safe and reliable environment. Yet, there are many unknowns about specific contributions of the building system and its design and performance on indoor air quality (IAQ) improvements. (2) Methods: this study examined the combined effect of ventilation type, airflow rates, and filtration on IAQ in five different classrooms. Experiments were conducted by releasing inert surrogate particles into the classrooms and measuring the concentrations in various locations of the room. (3) Results: we showed that while the distribution of particles in the space is a complex function of space geometry and air distribution configurations, the average decay rate of contaminants is proportional to the number of air changes per hour in the room. (4) Conclusions: rooms with a central HVAC system responded quicker to an internal source of contamination than rooms with only fan coil units. Furthermore, increasing the ventilation rate without improved filtration is an inefficient use of energy.

"Everything is Connected": Health Lifestyles and Teenagers' Social Distancing Behaviors in the COVID-19 Pandemic

Social distancing during the COVID-19 pandemic requires people to engage in new health behaviors that are public, monitored, and often contested. Parents are typically considered responsible for controlling their children's behavior and instilling norms. We investigated how parents and teens managed teenagers' social distancing behaviors. Analyzing 100 longitudinal (2015-2020), dyadic qualitative interviews with teenagers and their parents in 20 families from two middle-class communities in which social distancing was normative, we found that preexisting health lifestyles were used to link social distancing behaviors to specific identities, norms, and understandings of health. The pandemic presented challenges resulting from contradictory threats to health, differing preferences, and conflicting social judgments. Parents responded to challenges by adhering to community norms and enforcing teens' social distancing behaviors. They drew on preexisting, individualized health lifestyles as cultural tools to justify social distancing messages, emphasizing group distinctions, morality, and worth in ways that perpetuated inequalities.

Surveillance of SARS-CoV-2 transmission in educational institutions, August to December 2020, Germany

This study aims at providing estimates on the transmission risk of SARS-CoV-2 in schools and day-care centres. We calculated secondary attack rates (SARs) using individual-level data from state-wide mandatory notification of index cases in educational institutions, followed by contact tracing and PCR-testing of high-risk contacts. From August to December 2020, every sixth of overall 784 independent index cases was associated with secondary cases in educational institutions. Monitoring of 14 594 institutional high-risk contacts (89% PCR-tested) of 441 index cases during quarantine revealed 196 secondary cases (SAR 1.34%, 0.99-1.78). SARS-CoV-2 infection among high-risk contacts was more likely around teacher-indexes compared to student-/child-indexes (incidence rate ratio (IRR) 3.17, 1.79-5.59), and in day-care centres compared to secondary schools (IRR 3.23, 1.76-5.91), mainly due to clusters around teacher-indexes in day-care containing a higher mean number of secondary cases per index case (142/113 = 1.26) than clusters around student-indexes in schools (82/474 = 0.17). In 2020, SARS-CoV-2 transmission risk in educational settings was low overall, but varied strongly between setting and role of the index case, indicating the chance for targeted intervention. Surveillance of SARS-CoV-2 transmission in educational institutions can powerfully inform public health policy and improve educational justice during the pandemic.

Spa therapy interventions for post respiratory rehabilitation in COVID-19 subjects: does the review of recent evidence suggest a role?

Pulmonary rehabilitation is essential in post-COVID subjects, reporting respiratory impairment after the discharge from the hospital. Because the number of patients with respiratory outcomes is high and there are few facilities available, we wonder if a spa setting could represent a valid out-of-hospital alternative. We aim to explore recent evidence related to respiratory rehabilitation in the spa environment to understand if it can represent an appropriate setting for respiratory rehabilitation interventions in post-COVID subjects. Studies were found by screening PubMed, MEDLINE, and Google Scholar databases from 2011 up to February 2021. Studies were eligible if they were reviews, randomized controlled trials (RCTs), or clinical trials, investigating respiratory interventions in the spa environment. Recent evidence has shown that inhalations and mineral-rich water immersions are effective in fighting and preventing multiple chronic respiratory tract diseases. Therefore, these treatments could also be applied to post-COVID patients with medium long-term respiratory outcomes.

Model-based assessment of SARS-CoV-2 Delta variant transmission dynamics within partially vaccinated K-12 school populations

BACKGROUND

We examined school reopening policies amidst rising transmission of the highly transmissible Delta variant, accounting for vaccination among individuals aged 12 years and older, with the goal of characterizing risk to students and teachers under various within-school non-pharmaceutical interventions (NPIs) combined with specific vaccination coverage levels.

METHODS

We developed an individual-based transmission model to simulate transmission of the Delta variant of SARS-CoV-2 among a synthetic population, representative of Bay Area cities. We parameterized the model using community contact rates from vaccinated households ascertained from a household survey of Bay Area families with children conducted between February - April, 2021.

INTERVENTIONS AND OUTCOMES

We evaluated the additional infections in students and teachers/staff resulting over a 128-day semester from in-school instruction compared to remote instruction when various NPIs (mask use, cohorts, and weekly testing of students/teachers) were implemented in schools, across various community-wide vaccination coverages (50%, 60%, 70%), and student (≥12 years) and teacher/staff vaccination coverages (50% - 95%). We quantified the added benefit of universal masking over masking among unvaccinated students and teachers, across varying levels of vaccine effectiveness (45%, 65%, 85%), and compared results between Delta and Alpha variant circulation.

RESULTS

The Delta variant sharply increases the risk of within-school COVID-transmission when compared to the Alpha variant. In our highest risk scenario (50% community and within-school vaccine coverage, no within-school NPIs, and predominant circulation of the Delta variant), we estimated that an elementary school could see 33-65 additional symptomatic cases of COVID-19 over a four-month semester (depending on the relative susceptibility of children <10 years). In contrast, under the Bay Area reopening plan (universal mask use, community and school vaccination coverage of 70%), we estimated excess symptomatic infection attributable to school reopening among 2.0-9.7% of elementary students (8-36 excess symptomatic cases per school over the semester), 3.0% of middle school students (13 cases per school) and 0.4% of high school students (3 cases per school). Excess rates among teachers attributable to reopening were similar. Achievement of lower risk tolerances, such as <5 excess infections per 1,000 students or teachers, required a cohort approach in elementary and middle school populations. In the absence of NPIs, increasing the vaccination coverage of community members from 50% to 70% or elementary teachers from 70% to 95% reduced the estimated excess rate of infection among elementary school students attributable to school transmission by 24% and 41%, respectively. We estimated that with 70% coverage of the eligible community and school population with a vaccine that is ≤65% effective, universal masking can avert more cases than masking of unvaccinated persons alone.

CONCLUSIONS

Amidst circulation of the Delta variant, our findings demonstrated that schools are not inherently low risk, yet can be made so with high community vaccination coverages and universal masking. Vaccination of adult community members and teachers protects unvaccinated elementary and middle school children. Elementary and middle schools that can support additional interventions, such as cohorts and testing, should consider doing so, particularly if additional studies find that younger children are equally as susceptible as adults to the Delta variant of SARS-CoV-2.

LIMITATIONS

We did not consider the effect of social distancing in classrooms, or variation in testing frequency, and considerable uncertainty remains in key transmission parameters.

covid19.Explorer: a web application and R package to explore United States COVID-19 data

Appearing at the end of 2019, a novel virus (later identified as SARS-CoV-2) was characterized in the city of Wuhan in Hubei Province, China. As of the time of writing, the disease caused by this virus (known as COVID-19) has already resulted in over three million deaths worldwide. SARS-CoV-2 infections and deaths, however, have been highly unevenly distributed among age groups, sexes, countries, and jurisdictions over the course of the pandemic. Herein, I present a tool (the covid19.Explorer R package and web application) that has been designed to explore and analyze publicly available United States COVID-19 infection and death data from the 2020/21 U.S. SARS-CoV-2 pandemic. The analyses and visualizations that this R package and web application facilitate can help users better comprehend the geographic progress of the pandemic, the effectiveness of non-pharmaceutical interventions (such as lockdowns and other measures, which have varied widely among U.S. states), and the relative risks posed by COVID-19 to different age groups within the U.S. population. The end result is an interactive tool that will help its users develop an improved understanding of the temporal and geographic dynamics of the SARS-CoV-2 pandemic, accessible to lay people and scientists alike.

Presentation of a participatory approach to develop preventive measures to reduce COVID-19 transmission in child care

Background

It can be suspected that work in child care facilities is associated with an elevated exposure risk towards SARS-CoV-2 infections. It is still unclear under which conditions employees in those facilities can safely pursue their work. Preventive workplace-related measures to reduce transmission dynamics in this work environment need to be developed. These measures need to build on a solid scientific foundation and be ready for practical use at the same time. Therefore, the aim of the study is to present a participatory approach to identify, minimize, and eliminate workplace-specific COVID-19 transmission within child care. The approach presented combines quantitative as well as qualitative elements and includes a screening of critical workplace conditions and the development of preventive measures to foster a safe workplace design.

Methods

First, 428 employees of different child care facilities in a large German city reported their subjective risk of infection, fear of infection, and support received by the employer. Second, the participants commented in detail about high risk conditions during work. Third, employees provided suggestions for preventive measures. We conducted a qualitative analysis of free text answers to evaluate which aspects are perceived as critical from an employee perspective.

Results

Participants provided valuable and practicable ideas on how to design and improve preventive measures to reduce COVID-19 transmission in child care dealing with structural conditions, the interaction with the parents, the implementation of preventive measures and recommendations for policy makers.

Conclusions

These new insights help to organize pandemic risk management in order to align theoretical based measures with the practical realization. We encourage researchers to adapt the approach presented to other work areas in order to foster participation of employees in work design to reduce COVID-19 transmission.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12995-021-00316-0.

COVID-19: captures iron and generates reactive oxygen species to damage the human immune system

Currently, the novel coronavirus pneumonia has been widespread globally, and there is no specific medicine. In response to the emergency, we employed bioinformatics methods to investigate the virus's pathogenic mechanism, finding possible control methods. We speculated in previous studies that E protein was associated with viral infectivity. The present study adopted the domain search techniques to analyse the E protein. According to the results, the E protein could bind iron or haem. The iron and haem bound by the E protein came from the attacked haemoglobin and phagocytes. When E protein was attached to haem, it synthesised oxygen and water into superoxide anions, hydrogen peroxide and hydroxyl radicals. When the iron-bound E protein and the haem-bound E protein worked together, they converted superoxide anions and hydrogen peroxide into oxygen and water. These were the "ROS attack" and "ROS escape" of the virus. "ROS attack" damaged the tissues or cells exposed on the surface of the virus, and "ROS escape" decomposed the superoxide anion and hydrogen peroxide that attacked the virus. When NK cells were exposed to infected cells, viruses that had not shed from the infected cells' surface damaged them through "ROS attack". In addition, lymphocytes such as T cells and B cells, which could be close to the antigen of the virus surface, were also easily damaged or killed by the "ROS attack", generating a decrease in lymphocytes. When memory B cells were exposed to the virus's surface antigen, they were also damaged by "ROS attack", resulting in the patient's re-infection. The virus applied the "ROS escape" to decompose hydrogen peroxide released by phagocytes into oxygen and water. The surrounding cells were replenished with oxygen, and the patient was in a "happy hypoxia" state. When the phagocytes swallowed the virus, the E protein converted superoxide anions into oxygen and water. In this way, the virus parasitized in the vesicles of the phagocyte. While virus was in the lysosome, the E protein generated ROS to damage nearby hydrolases. In this way, the virus parasitized the lysosome. Excessive hydroxyl free radicals destroyed the membrane structure of the lysosome, causing the hydrolase release from lysosome, autophagy of phagocytic cells and subsequent cell death. As a result, the colonizing phagocytes of the virus was associated with asymptomatic infection or retest-positive. Briefly, the virus inhibited the immune system through "ROS escape", and damaged the immune system by "ROS attack". The destruction instigated a strong cytokine storm, leading to organ failure and complications.

High Infection Fatality Rate Among Elderly and Risk Factors Associated With Infection Fatality Rate and Asymptomatic Infections of COVID-19 Cases in Hong Kong

Background: Since the emergence in December 2019, the COVID-19 pandemic has become one of the greatest global public health threats in history. However, asymptomatic infections have increased the challenges of providing accurate estimates for the infection fatality rate (IFR) of COVID-19. Methods: We calculated the asymptomatic case ratios based on the reported COVID-19 cases in Hong Kong where intensive testing has been conducted in close contacts and high-risk populations. We estimated the IFR using both symptomatic and asymptomatic cases as denominator. The boosted regression tree (BRT) and multivariable logistic regression models were used to identify relative contribution and effect size of the risk factors associated with the asymptomatic cases and IFRs. Results: The ratio of the asymptomatic patients in Hong Kong was higher than many other regions over the world. Imported cases had a higher asymptomatic proportion than local cases. Older age and male were associated with a higher IFR than younger age and females. Conclusion: Policymakers should consider the potential risk factors for the asymptomatic infections and IFRs by the Hong Kong surveillance data to mitigate the diseases and reduce the case mortality of COVID-19.

Simulation-based evaluation of school reopening strategies during COVID-19: A case study of São Paulo, Brazil

During the coronavirus disease 2019 (COVID-19) pandemic, many countries opted for strict public health measures, including closing schools. After some time, they have started relaxing some of those restrictions. To avoid overwhelming health systems, predictions for the number of new COVID-19 cases need to be considered when choosing a school reopening strategy. Using a computer simulation based on a stochastic compartmental model that includes a heterogeneous and dynamic network, we analyse different strategies to reopen schools in the São Paulo Metropolitan Area, including one similar to the official reopening plan. Our model allows us to describe different types of relations between people, each type with a different infectiousness. Based on our simulations and model assumptions, our results indicate that reopening schools with all students at once has a big impact on the number of new COVID-19 cases, which could cause a collapse of the health system. On the other hand, our results also show that a controlled school reopening could possibly avoid the collapse of the health system, depending on how people follow sanitary measures. We estimate that postponing the schools' return date for after a vaccine becomes available may save tens of thousands of lives just in the São Paulo Metropolitan Area compared to a controlled reopening considering a worst-case scenario. We also discuss our model constraints and the uncertainty of its parameters.

Community and Campus COVID-19 Risk Uncertainty Under University Reopening Scenarios: Model-Based Analysis

BACKGROUND

Significant uncertainty has existed about the safety of reopening college and university campuses before the COVID-19 pandemic is better controlled. Moreover, little is known about the effects that on-campus students may have on local higher-risk communities.

OBJECTIVE

We aimed to estimate the range of potential community and campus COVID-19 exposures, infections, and mortality under various university reopening plans and uncertainties.

METHODS

We developed campus-only, community-only, and campus × community epidemic differential equations and agent-based models, with inputs estimated via published and grey literature, expert opinion, and parameter search algorithms. Campus opening plans (spanning fully open, hybrid, and fully virtual approaches) were identified from websites and publications. Additional student and community exposures, infections, and mortality over 16-week semesters were estimated under each scenario, with 10% trimmed medians, standard deviations, and probability intervals computed to omit extreme outliers. Sensitivity analyses were conducted to inform potential effective interventions.

RESULTS

Predicted 16-week campus and additional community exposures, infections, and mortality for the base case with no precautions (or negligible compliance) varied significantly from their medians (4- to 10-fold). Over 5% of on-campus students were infected after a mean of 76 (SD 17) days, with the greatest increase (first inflection point) occurring on average on day 84 (SD 10.2 days) of the semester and with total additional community exposures, infections, and mortality ranging from 1-187, 13-820, and 1-21 per 10,000 residents, respectively. Reopening precautions reduced infections by 24%-26% and mortality by 36%-50% in both populations. Beyond campus and community reproductive numbers, sensitivity analysis indicated no dominant factors that interventions could primarily target to reduce the magnitude and variability in outcomes, suggesting the importance of comprehensive public health measures and surveillance.

CONCLUSIONS

Community and campus COVID-19 exposures, infections, and mortality resulting from reopening campuses are highly unpredictable regardless of precautions. Public health implications include the need for effective surveillance and flexible campus operations.

School closures reduced social mixing of children during COVID-19 with implications for transmission risk and school reopening policies

School closures may reduce the size of social networks among children, potentially limiting infectious disease transmission. To estimate the impact of K-12 closures and reopening policies on children's social interactions and COVID-19 incidence in California's Bay Area, we collected data on children's social contacts and assessed implications for transmission using an individual-based model. Elementary and Hispanic children had more contacts during closures than high school and non-Hispanic children, respectively. We estimated that spring 2020 closures of elementary schools averted 2167 cases in the Bay Area (95% CI: -985, 5572), fewer than middle (5884; 95% CI: 1478, 11.550), high school (8650; 95% CI: 3054, 15 940) and workplace (15 813; 95% CI: 9963, 22 617) closures. Under assumptions of moderate community transmission, we estimated that reopening for a four-month semester without any precautions will increase symptomatic illness among high school teachers (an additional 40.7% expected to experience symptomatic infection, 95% CI: 1.9, 61.1), middle school teachers (37.2%, 95% CI: 4.6, 58.1) and elementary school teachers (4.1%, 95% CI: -1.7, 12.0). However, we found that reopening policies for elementary schools that combine universal masking with classroom cohorts could result in few within-school transmissions, while high schools may require masking plus a staggered hybrid schedule. Stronger community interventions (e.g. remote work, social distancing) decreased the risk of within-school transmission across all measures studied, with the influence of community transmission minimized as the effectiveness of the within-school measures increased.

Assessing asymptomatic, pre-symptomatic and symptomatic transmission risk of SARS-CoV-2

BACKGROUND

The relative contributions of asymptomatic, pre-symptomatic and symptomatic transmission of SARS-CoV-2 have not been clearly measured although control measures may differ in response to the risk of spread posed by different types of cases.

METHODS

We collected detailed information on transmission events and symptom status based on laboratory-confirmed patient data and contact tracing data from four provinces and one municipality in China. We estimated the variation in risk of transmission over time, and the severity of secondary infections, by symptomatic status of the infector.

RESULTS

There were 393 symptomatic index cases with 3136 close contacts and 185 asymptomatic index cases with 1078 close contacts included into the study. The secondary attack rate among close contacts of symptomatic and asymptomatic index cases were 4.1% (128/3136) and 1.1% (12/1078), respectively, corresponding to a higher transmission risk from symptomatic cases than from asymptomatic cases (OR: 3.79, 95% CI: 2.06, 6.95). Approximately 25% (32/128) and 50% (6/12) of the infected close contacts were asymptomatic from symptomatic and asymptomatic index cases, respectively, while more than one third (38%) of the infections in the close contacts of symptomatic cases were attributable to exposure to the index cases before symptom onset. Infected contacts of asymptomatic index cases were more likely to be asymptomatic and less likely to be severe.

CONCLUSIONS

Asymptomatic and pre-symptomatic transmission play an important role in spreading infection, although asymptomatic cases pose a lower risk of transmission than symptomatic cases. Early case detection and effective test-and-trace measures are important to reduce transmission.

Reducing COVID-19 risk in schools: a qualitative examination of secondary school staff and family views and concerns in the South West of England

OBJECTIVE

To investigate student, parent/carer and secondary school staff attitudes towards school COVID-19 mitigation measures.

METHODS

Recruitment used school communication, community organisations and snowball sampling in South West England. Audio recorded online or phone individual/group semi-structured interviews were conducted in July-Septtember 2020 and lasted 30-60 min. Interviews focused on views towards social distancing, hand hygiene and testing. Framework analysis was performed on interview notes/transcripts.

RESULTS

Participants were 15 staff, 20 parents and 17 students (11-16 years) from 14 diverse schools. Concerns about COVID-19 risk at school, especially to vulnerable individuals, were outweighed by perceived risks of missed learning. Some staff felt guilt around being a potential 'spreader' by teaching multiple classes. Findings highlighted a wide variety of school COVID-19 mitigation measures being deployed due to ambiguous government guidance. Participants generally saw mitigation measures as an acceptable and pragmatic solution to the perceived impossibility of social distancing in crowded schools, although anticipated challenges changing habitual behaviour. Participants supported school COVID-19 testing but identified the need to consider data security and stigma around COVID-19 diagnosis. Staff were concerned about unintended consequences of risk-reduction strategies on student behaviour, learning and pastoral care, particularly for those with Special Educational Needs or mental health issues who may find the measures especially challenging, and resultant widening inequalities.

CONCLUSION

Families and staff supported COVID-19 mitigation measures in schools and would welcome the roll out school COVID-19 testing. Clear messaging and engendering collective responsibility are important for compliance and success of COVID-19 mitigation measures. However, schools and policy-makers should consider unintended consequences of measures, providing extra support for vulnerable students and those with additional needs, and consider ways to avoid widening educational and health inequalities. Findings demonstrate the acceptability of school COVID-19 infection control measures is likely to be influenced by the balance of risks and benefits to students.

Youth Mask-Wearing and Social-Distancing Behavior at In-Person High School Graduations During the COVID-19 Pandemic

PURPOSE

Reopening schools during the COVID-19 pandemic is a challenging policy issue that requires mitigation strategies, such as mask-wearing and social distancing. Whether youth will conform to these strategies is unclear.

METHODS

We leverage data on 1,152 youth's mask-wearing and social-distancing behaviors from observations of five in-person live-streamed high school graduations from one U.S. public school district in July 2020. Multiple researchers took ethnographic field notes and systematically recorded public health behaviors for each graduation. We also use data from the local public health department, school district, newspapers, community observations, and the National Center for Education Statistics. We then conducted a descriptive quantitative analysis of mask-wearing status by gender, ethnicity, and school, along with a qualitative thematic analysis.

RESULTS

Nearly 70% of students wore their masks properly while receiving their diploma, although 9.6% wore no mask and 18.7% struggled with mask fit. Almost all students removed masks for graduation photos after adults suggested they should, although 80% of them were wearing their mask properly before the photo. We found significant school variation, but no gender or ethnic variation in student mask-wearing. School variation aligned with political themes of student speeches and in adult commitment to safety measures. Student speakers at all schools mentioned altruistic concern about COVID-19. All schools struggled with social distancing throughout the ceremony, except when students were seated in socially distanced chairs.

CONCLUSIONS

This study provides important insights into youth conformity to COVID-19 guidelines and strategies to protect public health during in-person schooling.

Reopening Schools and the Dynamics of SARS-CoV-2 Infections in Israel: A Nationwide Study

BACKGROUND

The benefits of school reopening must be weighed against the morbidity and mortality risks and the impact of enhancing spread of COVID-19. We investigated the effects of school reopening and easing of social distancing restrictions on the dynamics of SARS-CoV-2 infections in Israel, between March-July 2020.

METHODS

We examined the nationwide agewise weekly incidence, prevalence, SARS-CoV-2 PCR tests, their positivity, COVID-19 hospitalizations and associated mortality. Temporal differences in these parameters following school reopening, school ending, and following easing of restrictions such as permission of large scale gatherings, were examined.

RESULTS

The incidence of SARS-CoV-2 infections gradually increased following school reopening in all age groups, with a significantly higher increase in adults compared to children. Higher relative ratios (RRs) of sample positivity rates 21-27 days following school reopening relative to positivity rates prior to openings were found for the age groups 40-59 (RR: 4.72, 95% CI: 3.26 - 6.83) and 20-39 years (RR: 3.37 [2.51 - 4.53]), but not for children aged 0-9 (RR: 1.46 [0.85 - 2.51]) and 10-19 years (RR: 0.93 [0.65 - 1.34]).No increase was observed in COVID-19 associated hospitalizations and deaths following school reopening. In contrast, permission of large-scale gatherings was accompanied by increases in incidence and positivity rates of samples for all age groups, and increased hospitalizations and mortality.

CONCLUSIONS

This analysis does not support a major role of school reopening in the resurgence of the COVID-19 curve in Israel. Easing restrictions on large scale gatherings was the major influence on this resurgence.

Reopening Schools After a Novel Coronavirus Surge

The coronavirus disease 2019 (COVID-19) pandemic shook the world in ways not seen since the pandemic influenza of 1918-1919. As of late August 2020, over 25 million persons had been infected, and we will see the global death toll exceed one million by the end of 2020. Both are minimum estimates. All segments of society have been drastically affected. Schools worldwide have been forced to close due to illness and absenteeism, transmission and risk to vulnerable members of the school community, and community concerns. The decision to reopen school during a pandemic will have a tremendous impact on children's safety, growth, and well-being. Not opening invites social isolation and suboptimal educational experiences, especially for youth whose computing assets and online access are limited and those with special needs. The opening has hazards as well, and the mitigation of these risks is the topic of this chapter. Opening schools requires careful considerations of benefits, risks, and precautions. Guiding principles for safety and strategic application of the principles in each educational niche are critical issues to consider during school reopening. The fundamental principles of disease control involve school-directed initiatives (physical distancing and mask use, hand/face and surface cleansing, administrative controls, engineering controls) and individual-level risk reduction approaches to maximize adherence to new guidelines. The school-initiated "top-down" approaches and the individual-level "bottom-up" approaches must be synergized, as no single method will ensure safety. We discuss how to effectively layer strategies in each educational space to increase safety. Since the vulnerability of children has been heightened during this pandemic crisis, we highlight the special considerations for mental health support that should be considered by schools. The safety principles, disease control strategies, and other critical issues discussed here will serve as a starting point for developing a safe, comprehensive, and feasible reopening plan.

Comparison of Clinical and Laboratory Features and Treatment Options of 237 Symptomatic and Asymptomatic Children Infected with SARS-CoV-2 in the Early Phase of the COVID-19 Pandemic in Turkey

Little is known about the therapeutic use of hydroxychloroquine in pediatric patients with coronavirus disease 2019 (COVID-19). Here, we retrospectively retrieved data of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR-positive pediatric patients from 20 hospitals in 8 Turkish cities. We obtained epidemiological, clinical, and laboratory features of the patients, as well as the drugs used for treating COVID-19. A total of 237 nasopharyngeal swab SARS-CoV-2 PCR-positive children were included in the study from March 26, 2020 to June 20, 2020. The mean age of asymptomatic children (118 ± 62 months) was higher than that of symptomatic children (89 ± 69 months). Symptomatic children had significantly lower mean lymphocyte counts and higher mean CRP, D-dimer, procalcitonin, and LDH levels than asymptomatic children in the univariate analysis. Among 156 children, 78 (50%), 15, 44, and 21 were treated with a hydroxychloroquine-containing regimen, hydroxychloroquine + azithromycin + oseltamivir, hydroxychloroquine + azithromycin, and hydroxychloroquine alone, respectively. Among 156 patients who received medical treatment, 90 (58%) underwent pre- and/or post-treatment electrocardiogram (ECG). However, none of them had ECG abnormalities or required hydroxychloroquine discontinuation due to adverse drug reactions.

Bioinformatic study to discover natural molecules with activity against COVID-19

Background: In 2020, the world has struggled to deal with coronavirus disease 2019 (COVID-19), which started in 2019 in China and has spread throughout the globe, affecting at least 31,175,835 humans globally and claiming 962,634 lives reported till 22nd September, 2020 by the World Health Organization. The main causative agent for this disease is known as severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). So far, there is no cure or proven therapeutics available till date. Therefore, we undertook this study to find the most probable drug candidate through a bioinformatics study.

Methods: Thus, we virtually screened the Zinc natural database using HTVS tool through molecular docking studies to analyze molecules recommended for the treatment of COVID-19.

Results: Ramipril benzyl ester, propafenone dimer and Lariciresinol are three important drugs found from the present study due to their medicinal application which could be helpful in treating the disease. Stylopine, quillaic acid, cinobufagin, vitisinol C, segetalin A, scopolamine, 3-oxo glycyrrhetinic acid, conchinone B, lactimidomycin and cardinalins 4 are the other lead molecules that could be used as therapeutics against COVID-19 disease.

Conclusions: The studied molecules could act as an effective inhibitory drug against COVID-19.

WITHDRAWN: Holidays over: a review of actual COVID-19 school outbreaks up to September 2020

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COVID-19 in the Pediatric Population-Review and Current Evidence

Purpose of Review

Coronavirus disease 2019 (COVID-19) pandemic has major health and economic impacts. We review disease characteristics in children.

Recent Findings

Children comprise 1–2% of the diagnosed cases, and typically suffer mild disease. The median age of infected children is 3.3–11 years, and male/female ratio is 1.15–1.55. Common symptoms in children include upper respiratory symptoms (26–54%), cough (44–54%), fever (32–65%), and gastrointestinal (15–30%) symptoms. Substantial proportion (4–23%) are asymptomatic. Death rates are up to 0.7%. Risk factors associated with severe disease are neonatal age group, male gender, lower respiratory tract disease, and pre-existing medical conditions. Vertical transmission was reported. Multisystem inflammatory syndrome (MIS), characterized by fever, multisystem organ involvement, and laboratory markers of inflammation, causes critical illness in > 50% of cases and is increasingly reported from endemic countries. Indirect effects of the coronavirus epidemic include higher rates of psychiatric morbidities, education loss, unhealthy lifestyle changes, and increased child neglect. Vaccines are in clinical trials and immunogenicity has not yet been shown in children.

Summary

Overall, COVID-19 has lower incidence and causes milder disease in children compared with adult patients. MIS is a rare severe complication more common in children. More data on the efficacy and safety of antivirals in children are needed.

Potential Community and Campus Covid-19 Outcomes Under University and College Reopening Scenarios

BACKGROUND

Significant uncertainty exists in many countries about the safety of, and best strategies for, reopening college and university campuses until the Covid-19 pandemic is better controlled. Little also is known about the effects on-campus students may have on local higher-risk communities. We aimed to estimate potential community and campus Covid-19 exposures, infections, and mortality due to various university reopening and precaution plans under current ranges of assumptions and uncertainties.

METHODS

We developed and calibrated campus-only, community-only, and campus-x-community epidemic differential equation and agent-based models. Input parameters for campus and surrounding communities were estimated via published and grey literature, scenario development, expert opinion, accuracy optimization algorithms, and Monte Carlo simulation; models were cross-validated against each other using February-June 2020 data from heterogeneous U.S. counties and states. Campus opening plans (spanning various fully open, hybrid, and fully virtual approaches) were identified from websites and publications. All scenarios were simulated assuming 16-week semesters and estimated ranges for Covid-19 prevalence among community residents and arriving students, precaution compliance, contact frequency, virus attack rates, and tracing and isolation effectiveness. Additional student and community exposures, infections, and mortality were estimated under each scenario, with 10% trimmed medians, standard deviations, and probability intervals computed to omit extreme outlier scenarios. Factorial analyses were conducted to identify intervention inputs with largest and smallest effects.

RESULTS

As a base case with no precautions (or no compliance), predicted 16-week student infections and mortality under normal operations ranged significantly from 471 to 9,495 (median: 2,286, SD: 2,627) and 0 to 123 (median: 9, SD: 14) per 10,000 students, respectively. The maximum active exposures across a semester was 15.76% of all students warranting tracing. Total additional community exposures, infections, and mortality ranged from 1 to 187, 13 to 820, and 1 to 21 per 10,000 residents, respectively. 1% and 5% of on-campus students were infected after a mean (SD) of 11 (3) and 76 (17) days, respectively; >10% students infected by the end of a semester in 34.8% of scenarios, with the greatest increase (first inflection point) occurring on aver-age on day 84 (SD: 10.2 days). Common reopening precautions reduced infections by 24% to 26% and mortality by 36% to 50% in both populations. Uncertainties in many factors, however, produced tremendous variability in all results, ranging from medians by -67% to +342%.

CONCLUSIONS

Consequences on community and student Covid-19 exposures, infections, and mortality of reopening physical campuses are very highly unpredictable, depending on a combination of random chance, controllable (e.g. physical layouts), and uncontrollable (e.g. human behavior) factors. Implications include needs for criteria to adapt campus operations mid-semester, methods to detect when necessary, and contingency plans for doing so.

The effect of school closures and reopening strategies on COVID-19 infection dynamics in the San Francisco Bay Area: a cross-sectional survey and modeling analysis

Background Large-scale school closures have been implemented worldwide to curb the spread of COVID-19. However, the impact of school closures and re-opening on epidemic dynamics remains unclear. Methods We simulated COVID-19 transmission dynamics using an individual-based stochastic model, incorporating social-contact data of school-aged children during shelter-in-place orders derived from Bay Area (California) household surveys. We simulated transmission under observed conditions and counterfactual intervention scenarios between March 17-June 1, and evaluated various fall 2020 K-12 reopening strategies. Findings Between March 17-June 1, assuming children <10 were half as susceptible to infection as older children and adults, we estimated school closures averted a similar number of infections (13,842 cases; 95% CI: 6,290, 23,040) as workplace closures (15,813; 95% CI: 9,963, 22,617) and social distancing measures (7,030; 95% CI: 3,118, 11,676). School closure effects were driven by high school and middle school closures. Under assumptions of moderate community transmission, we estimate that fall 2020 school reopenings will increase symptomatic illness among high school teachers (an additional 40.7% expected to experience symptomatic infection, 95% CI: 1.9, 61.1), middle school teachers (37.2%, 95% CI: 4.6, 58.1), and elementary school teachers (4.1%, 95% CI: -1.7, 12.0). Results are highly dependent on uncertain parameters, notably the relative susceptibility and infectiousness of children, and extent of community transmission amid re-opening. The school-based interventions needed to reduce the risk to fewer than an additional 1% of teachers infected varies by grade level. A hybrid-learning approach with halved class sizes of 10 students may be needed in high schools, while maintaining small cohorts of 20 students may be needed for elementary schools. Interpretation Multiple in-school intervention strategies and community transmission reductions, beyond the extent achieved to date, will be necessary to avoid undue excess risk associated with school reopening. Policymakers must urgently enact policies that curb community transmission and implement within-school control measures to simultaneously address the tandem health crises posed by COVID-19 and adverse child health and development consequences of long-term school closures.