Lifting Universal Masking in Schools - Covid-19 Incidence among Students and Staff

Wearing masks is easy but taking them off is difficult - A situation in Japan during COVID-19 pandemic and after

Background

Masks are well accepted in Japan, where they were already part of daily life even before the COVID-19 pandemic. Unlike many other countries where mask mandates were lifted as soon as the pandemic was under control, Japan was one of the last countries to ease mask-wearing guidelines. Even after the formal announcement to allow masks-off in mid-March 2023, many Japanese still voluntarily wear masks. In this work, possible reasons for this extreme "mask-affinity" of Japanese people were studied by exploring various information sources including tweets (now known as X posts) and subsequent text-analysis, online news, and medical literature.

Methods

An observational study was conducted based on tweets prospectively collected during 5 months from June 26th, 2022 to November 26th, 2022. Tweets with the hashtag "mask (in Japanese)" were collected weekly via the Twitter application programming interface by using R version 4.0.3 to gauge public opinions. The word clouds to allow intuitive understanding of the key words were drawn from the tokenized text.

Results

The data collection period included the 7th flareups of the newly infected cases i.e. "the 7th surge". In total, 161,592 tweets were collected. Word clouds for 1) before the 7th surge based on 18,000 tweets on June 26th and 2) during/after the 7th surge based on 143,592 tweets between July-November were created with the R package "wordcloud2". The results indicated that the people wanted to take off masks due to the heat in summer, then shifted again toward mask-wearing along with the 7th surge but with a certainly growing "no-mask" sentiment.

Conclusions

Subsequent review of domestic information sources suggested that various factors, not only well-known peer pressure, may have contributed the public's mask affinity in Japan. This work revealed an aspect of Japanese struggle toward adaptation to life in an unexpected pandemic by focusing on masks as our closest daily adjunct over the past 3 years of isolation.Trial registration: not applicable.

State variation in neighborhood COVID-19 burden across the United States

BACKGROUND

A lack of fine, spatially-resolute case data for the U.S. has prevented the examination of how COVID-19 infection burden has been distributed across neighborhoods, a key determinant of both risk and resilience. Without more spatially resolute data, efforts to identify and mitigate the long-term fallout from COVID-19 in vulnerable communities will remain difficult to quantify and intervene on.

METHODS

We leveraged spatially-referenced data from 21 states collated through the COVID Neighborhood Project to examine the distribution of COVID-19 cases across neighborhoods and states in the U.S. We also linked the COVID-19 case data with data on the neighborhood social environment from the National Neighborhood Data Archive. We then estimated correlations between neighborhood COVID-19 burden and features of the neighborhood social environment.

RESULTS

We find that the distribution of COVID-19 at the neighborhood-level varies within and between states. The median case count per neighborhood (coefficient of variation (CV)) in Wisconsin is 3078.52 (0.17) per 10,000 population, indicating a more homogenous distribution of COVID-19 burden, whereas in Vermont the median case count per neighborhood (CV) is 810.98 (0.84) per 10,000 population. We also find that correlations between features of the neighborhood social environment and burden vary in magnitude and direction by state.

CONCLUSIONS

Our findings underscore the importance that local contexts may play when addressing the long-term social and economic fallout communities will face from COVID-19.

Nasopharyngeal angiotensin converting enzyme 2 (ACE2) expression as a risk-factor for SARS-CoV-2 transmission in concurrent hospital associated outbreaks

BACKGROUND

Widespread human-to-human transmission of the severe acute respiratory syndrome coronavirus two (SARS-CoV-2) stems from a strong affinity for the cellular receptor angiotensin converting enzyme two (ACE2). We investigate the relationship between a patient's nasopharyngeal ACE2 transcription and secondary transmission within a series of concurrent hospital associated SARS-CoV-2 outbreaks in British Columbia, Canada.

METHODS

Epidemiological case data from the outbreak investigations was merged with public health laboratory records and viral lineage calls, from whole genome sequencing, to reconstruct the concurrent outbreaks using infection tracing transmission network analysis. ACE2 transcription and RNA viral load were measured by quantitative real-time polymerase chain reaction. The transmission network was resolved to calculate the number of potential secondary cases. Bivariate and multivariable analyses using Poisson and Negative Binomial regression models was performed to estimate the association between ACE2 transcription the number of SARS-CoV-2 secondary cases.

RESULTS

The infection tracing transmission network provided n = 76 potential transmission events across n = 103 cases. Bivariate comparisons found that on average ACE2 transcription did not differ between patients and healthcare workers (P = 0.86). High ACE2 transcription was observed in 98.6% of transmission events, either the primary or secondary case had above average ACE2. Multivariable analysis found that the association between ACE2 transcription (log2 fold-change) and the number of secondary transmission events differs between patients and healthcare workers. In health care workers Negative Binomial regression estimated that a one-unit change in ACE2 transcription decreases the number of secondary cases (β = -0.132 (95%CI: -0.255 to -0.0181) adjusting for RNA viral load. Conversely, in patients a one-unit change in ACE2 transcription increases the number of secondary cases (β = 0.187 (95% CI: 0.0101 to 0.370) adjusting for RNA viral load. Sensitivity analysis found no significant relationship between ACE2 and secondary transmission in health care workers and confirmed the positive association among patients.

CONCLUSION

Our study suggests that ACE2 transcription has a positive association with SARS-CoV-2 secondary transmission in admitted inpatients, but not health care workers in concurrent hospital associated outbreaks, and it should be further investigated as a risk-factor for viral transmission.

Looking under the lamp-post: quantifying the performance of contact tracing in the United States during the SARS-CoV-2 pandemic

Contact tracing forms a crucial part of the public-health toolbox in mitigating and understanding emergent pathogens and nascent disease outbreaks. Contact tracing in the United States was conducted during the pre-Omicron phase of the ongoing COVID-19 pandemic. This tracing relied on voluntary reporting and responses, often using rapid antigen tests due to lack of accessibility to PCR tests. These limitations, combined with SARS-CoV-2's propensity for asymptomatic transmission, raise the question "how reliable was contact tracing for COVID-19 in the United States"? We answered this question using a Markov model to examine the efficiency with which transmission could be detected based on the design and response rates of contact tracing studies in the United States. Our results suggest that contact tracing protocols in the U.S. are unlikely to have identified more than 1.65% (95% uncertainty interval: 1.62-1.68%) of transmission events with PCR testing and 1.00% (95% uncertainty interval 0.98-1.02%) with rapid antigen testing. When considering a more robust contact tracing scenario, based on compliance rates in East Asia with PCR testing, this increases to 62.7% (95% uncertainty interval: 62.6-62.8%). We did not assume presence of asymptomatic transmission or superspreading, making our estimates upper bounds on the actual percentages traced. These findings highlight the limitations in interpretability for studies of SARS-CoV-2 disease spread based on U.S. contact tracing and underscore the vulnerability of the population to future disease outbreaks, for SARS-CoV-2 and other pathogens.

Child mask mandates for COVID-19: a systematic review

BACKGROUND

Mask mandates for children during the COVID-19 pandemic varied in different locations. A risk-benefit analysis of this intervention has not yet been performed. In this study, we performed a systematic review to assess research on the effectiveness of mask wearing in children.

METHODS

We performed database searches up to February 2023. The studies were screened by title and abstract, and included studies were further screened as full-text references. A risk-of-bias analysis was performed by two independent reviewers and adjudicated by a third reviewer.

RESULTS

We screened 597 studies and included 22 in the final analysis. There were no randomised controlled trials in children assessing the benefits of mask wearing to reduce SARS-CoV-2 infection or transmission. The six observational studies reporting an association between child masking and lower infection rate or antibody seropositivity had critical (n=5) or serious (n=1) risk of bias; all six were potentially confounded by important differences between masked and unmasked groups and two were shown to have non-significant results when reanalysed. Sixteen other observational studies found no association between mask wearing and infection or transmission.

CONCLUSIONS

Real-world effectiveness of child mask mandates against SARS-CoV-2 transmission or infection has not been demonstrated with high-quality evidence. The current body of scientific data does not support masking children for protection against COVID-19.

In Support of Universal Admission Testing for SARS-CoV-2 During Significant Community Transmission

Many hospitals have stopped or are considering stopping universal admission testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We discuss reasons why admission testing should still be part of a layered system to prevent hospital-acquired SARS-CoV-2 infections during times of significant community transmission. These include the morbidity of SARS-CoV-2 in vulnerable patients, the predominant contribution of presymptomatic and asymptomatic people to transmission, the high rate of transmission between patients in shared rooms, and data suggesting surveillance testing is associated with fewer nosocomial infections. Preferences of diverse patient populations, particularly the hardest-hit communities, should be surveyed and used to inform prevention measures. Hospitals' ethical responsibility to protect patients from serious infections should predominate over concerns about costs, labor, and inconvenience. We call for more rigorous data on the incidence and morbidity of nosocomial SARS-CoV-2 infections and more research to help determine when to start, stop, and restart universal admission testing and other prevention measures.

Changes in surgical mortality during COVID-19 pandemic by patients' race, ethnicity and socioeconomic status among US older adults: a quasi-experimental event study model

OBJECTIVES

To examine changes in the 30-day surgical mortality rate after common surgical procedures during the COVID-19 pandemic and investigate whether its impact varies by urgency of surgery or patient race, ethnicity and socioeconomic status.

DESIGN

We used a quasi-experimental event study design to examine the effect of the COVID-19 pandemic on surgical mortality rate, using patients who received the same procedure in the prepandemic years (2016-2019) as the control, adjusting for patient characteristics and hospital fixed effects (effectively comparing patients treated at the same hospital). We conducted stratified analyses by procedure urgency, patient race, ethnicity and socioeconomic status (dual-Medicaid status and median household income).

SETTING

Acute care hospitals in the USA.

PARTICIPANTS

Medicare fee-for-service beneficiaries aged 65-99 years who underwent one of 14 common surgical procedures from 1 January 2016 to 31 December 2020.

MAIN OUTCOME MEASURES

30-day postoperative mortality rate.

RESULTS

Our sample included 3 620 689 patients. Surgical mortality was higher during the pandemic, with peak mortality observed in April 2020 (adjusted risk difference (aRD) +0.95 percentage points (pp); 95% CI +0.76 to +1.26 pp; p<0.001) and mortality remained elevated through 2020. The effect of the pandemic on mortality was larger for non-elective (vs elective) procedures (April 2020: aRD +0.44 pp (+0.16 to +0.72 pp); p=0.002 for elective; aRD +1.65 pp (+1.00, +2.30 pp); p<0.001 for non-elective). We found no evidence that the pandemic mortality varied by patients' race and ethnicity (p for interaction=0.29), or socioeconomic status (p for interaction=0.49).

CONCLUSIONS

30-day surgical mortality during the COVID-19 pandemic peaked in April 2020 and remained elevated until the end of the year. The influence of the pandemic on surgical mortality did not vary by patient race and ethnicity or socioeconomic status, indicating that once patients were able to access care and undergo surgery, surgical mortality was similar across groups.

Effect of wearing masks on odor detection and recognition

BACKGROUND

The effect of wearing masks on olfaction remains unclear.

OBJECTIVES

This study aimed to clarify the differences between the effects of no masks, surgical masks, and N95 respirator masks by conducting both identification and threshold olfaction tests.

METHODS

Young, healthy volunteers aged ≥ 18 years and < 30 years without awareness of apparent olfactory disorder were included. All participants filled out a questionnaire on olfaction and completed an acuity smell identification test (Open Essence test) and an olfactory threshold test (T&T olfactometry) while wearing no masks, surgical masks, or N95 respirator masks.

RESULTS

In the Open Essence tests, the no-mask group score was significantly higher than those of the surgical- and N95-mask groups. Using T&T olfactometry, the median-detection threshold of the no-mask group was significantly lower than that of the surgical-mask group, and the surgical-mask group threshold was significantly lower than that of the N95-mask group. Similar patterns were observed for the median-recognition threshold.

CONCLUSIONS

Wearing masks, especially an N95 mask, reduces the ability to detect and identify odors. This disadvantage should be considered by professionals such as healthcare workers, who require proper olfaction to perform appropriate tasks.

Does equipoise exist for masking children for COVID-19?

Clinical equipoise is characterized by genuine uncertainty within the medical community about the effectiveness of a medical intervention. Its existence is often deemed necessary for clinical trials and signals a need for higher quality evidence, most often with randomized controlled trials, before the intervention can be considered effective. A leading official of the United States' Centers for Disease Control and Prevention Director, when testifying before Congress in February of 2023, indicated there was no need for randomized controlled trials of masking because, owing to overwhelming evidence of benefit, there was no longer equipoise about masking children for COVID-19. We disagree with this statement and outline the reasons why in this piece. We review the concept of clinical equipoise specifically using the example of child masking. We list reasons equipoise still exists for masking children, including a lack of consensus among experts, contradictory medical evidence and recent and ongoing randomized efforts. Finally, we differentiate between clinical equipoise and ethical appropriateness. Despite ongoing equipoise about masking children, we outline why, owing to lack of evidence of net benefit, recommending this intervention does not currently appear to be medically ethical.

Association between face mask use and risk of SARS-CoV-2 infection: Cross-sectional study

We examined the association between face masks and risk of infection with SARS-CoV-2 using cross-sectional data from 3,209 participants in a randomized trial exploring the effectiveness of glasses in reducing the risk of SARS-CoV-2 infection. Face mask use was based on participants' response to the end-of-follow-up survey. We found that the incidence of self-reported COVID-19 was 33% (aRR 1.33; 95% CI 1.03-1.72) higher in those wearing face masks often or sometimes, and 40% (aRR 1.40; 95% CI 1.08-1.82) higher in those wearing face masks almost always or always, compared to participants who reported wearing face masks never or almost never. We believe the observed increase in the incidence of infection associated with wearing a face mask is likely due to unobservable and hence nonadjustable differences between those wearing and not wearing a mask. Observational studies reporting on the relationship between face mask use and risk of respiratory infections should be interpreted cautiously, and more randomized trials are needed.

Measuring Indoor Air Quality Does Not Prevent COVID-19

Boston Public Schools (BPS) closed for in-person learning in March 2020 due to COVID-19 and didn't fully reopen until the 2021-2022 school year. Due to the age of schools and absent ventilation systems, coupled with decades of disinvestment in the infrastructure, BPS entered the pandemic with serious challenges impacting the health of students and staff. These challenges were magnified by an infectious airborne virus. Instead of using this opportunity to improve ventilation systems, BPS opted to invest in an air quality monitoring system. This system only confirmed what was already known-there is poor ventilation in most school buildings. It did not lead to correction of new or long-standing problems. This failure has harmed the BPS community, which includes primarily low-income Black and Brown families. This article describes Boston's school system, its track record of inadequate attention to infrastructure, and explores pitfalls of focusing on evaluation instead of correction.

Development of a community-informed communication toolkit to prevent spread of viral illness in schools, including SARS-COV-2

Introduction

Schools were uniquely impacted during the COVID-19 (SARS-COV-2) pandemic. We sought to elucidate how parents/guardians of elementary and middle school students in Maryland navigated the return to in-person school following remote instruction. We also sought to understand how they perceived communication about school-based COVID-19 mitigation strategies and their preferences for the content and format of public health communication about COVID-19 mitigation in schools.

Methods

We engaged a community advisory board comprised of key partners and implemented a survey and focus groups.

Results

Results indicated that parents/guardians wanted clearer communication about COVID-19 mitigation policies in schools and were experiencing fatigue and confusion. These insights informed the development of a tailorable communication toolkit. The toolkit was designed to (1) inform parents/guardians about the importance and effectiveness of mitigation strategies for preventing viral spread to keep children in school, (2) promote a sense of community and support, and (3) help school communication teams effectively communicate information about mitigation strategies being implemented.

Discussion

We describe a process for leveraging schools as a trusted messenger, engaging school communities in the development of communication messages, and utilizing a tailorable communication toolkit in the context of shifting public health guidance and local needs. The toolkit development and dissemination process offers a model for targeting public health messaging to parents/guardians in school settings.

Evaluation of "Test to Return" after COVID-19 Diagnosis in a Massachusetts Public School District

BACKGROUND

Per Centers for Disease Control and Prevention guidance, students with COVID-19 may end isolation after 5 days if symptoms are improving; some individuals may still be contagious. Rapid antigen testing identifies possibly infectious virus. We report on a test-to-return (TTR) program in a Massachusetts school district to inform policy decisions about return to school after COVID-19.

METHODS

During the 2021-2022 Omicron BA.1 surge, students with COVID-19 could return on day 6-10 if they met symptom criteria and had a negative rapid test; students with positive rapid tests and those who declined TTR remained isolated until day 11. TTR positivity rates were compared by grade level, vaccination status, symptom status, and day of infection.

RESULTS

31.4% of students had a positive TTR rapid test; there were no differences by grade or vaccination status. Ever-symptomatic students were more likely to have a positive rapid test (75/174 [43.1%] vs 18/104 [17.3%]). For ever-symptomatic students, TTR positivity decreased by day of infection.

CONCLUSIONS

A substantial proportion of students may still be contagious 6 days after onset of COVID-19 infection. TTR programs may increase or reduce missed school days, depending on when return is otherwise allowed (day 6 or 11). The impact of TTR programs on school-associated transmission remains unknown.

Effect of SARS-CoV-2 prior infection and mRNA vaccination on contagiousness and susceptibility to infection

The immunity conferred by SARS-CoV-2 vaccines and infections reduces the transmission of the virus. To answer how the effect of immunity is shared between a reduction of infectiousness and an increased protection against infection, we examined >50,000 positive cases and >110,000 contacts from Geneva, Switzerland (June 2020 to March 2022). We assessed the association between secondary attack rate (i.e. proportion of new cases among contacts) and immunity from natural infection and/or vaccination, stratifying per four SARS-CoV-2 variants and adjusting for index cases and contacts' socio-demographic characteristics and the propensity of the contacts to be tested. Here we show that immunity protected contacts from infection, rather than reducing infectiousness of index cases. Natural infection conferred the strongest immunity. Hybrid immunity did not surpass recent infection. Although of smaller amplitude, the reduction in infectiousness due to vaccination was less affected by time and by the emergence of new SARS-CoV-2 variants than the susceptibility to infection. These findings support the role of vaccine in reducing infectiousness and underscore the complementary role of interventions reducing SARS-CoV-2 propagation, such as mask use or indoor ventilation.

SARS-CoV-2 transmission patterns in educational settings during the Alpha wave in Reggio-Emilia, Italy

Different monitoring and control policies have been implemented in schools to minimize the spread of SARS-CoV-2. Transmission in schools has been hard to quantify due to the large proportion of asymptomatic carriers in young individuals. We applied a Bayesian approach to reconstruct the transmission chains between 284 SARS-CoV-2 infections ascertained during 87 school outbreak investigations conducted between March and April 2021 in Italy. Under the policy of reactive quarantines, we found that 42.5% (95%CrI: 29.5-54.3%) of infections among school attendees were caused by school contacts. The mean number of secondary cases infected at school by a positive individual during in-person education was estimated to be 0.33 (95%CrI: 0.23-0.43), with marked heterogeneity across individuals. Specifically, we estimated that only 26.0% (95%CrI: 17.6-34.1%) of students and school personnel who tested positive during in-person education caused at least one secondary infection at school. Positive individuals who attended school for at least 6 days before being isolated or quarantined infected on average 0.49 (95%CrI: 0.14-0.83) secondary cases. Our findings provide quantitative insights on the contribution of school transmission to the spread of SARS-CoV-2 in young individuals. Identifying positive cases within 5 days after exposure to their infector could reduce onward transmission at school by at least 30%.

Effects of public-health measures for zeroing out different SARS-CoV-2 variants

Targeted public health interventions for an emerging epidemic are essential for preventing pandemics. During 2020-2022, China invested significant efforts in strict zero-COVID measures to contain outbreaks of varying scales caused by different SARS-CoV-2 variants. Based on a multi-year empirical dataset containing 131 outbreaks observed in China from April 2020 to May 2022 and simulated scenarios, we ranked the relative intervention effectiveness by their reduction in instantaneous reproduction number. We found that, overall, social distancing measures (38% reduction, 95% prediction interval 31-45%), face masks (30%, 17-42%) and close contact tracing (28%, 24-31%) were most effective. Contact tracing was crucial in containing outbreaks during the initial phases, while social distancing measures became increasingly prominent as the spread persisted. In addition, infections with higher transmissibility and a shorter latent period posed more challenges for these measures. Our findings provide quantitative evidence on the effects of public-health measures for zeroing out emerging contagions in different contexts.

Prevalence and Risk Factors for School-Associated Transmission of SARS-CoV-2

Importance

School-associated SARS-CoV-2 transmission is described as uncommon, although the true transmission rate is unknown.

Objective

To identify the SARS-CoV-2 secondary attack rate (SAR) in schools and factors associated with transmission.

Design, Setting, and Participants

This cohort study examined the risk of school-based transmission of SARS-CoV-2 among kindergarten through grade 12 students and staff in 10 Massachusetts school districts during 2 periods: fall 2020/spring 2021 (F20/S21) and fall 2021 (F21). School staff collected data on SARS-CoV-2 index cases and school-based contacts, and SAR was defined as the proportion of contacts acquiring SARS-CoV-2 infection.

Exposure

SARS-CoV-2.

Main Outcomes and Measures

Potential factors associated with transmission, including grade level, masking, exposure location, vaccination history, and Social Vulnerability Index (SVI), were analyzed using univariable and multivariable logistic regression models.

Results

For F20/S21, 8 school districts (70 schools, >33 000 students) were included and reported 435 index cases (151 staff, 216 students, and 68 missing role) with 1771 school-based contacts (278 staff, 1492 students, and 1 missing role). For F21, 5 districts (34 schools, >18 000 students) participated and reported 309 index cases (37 staff, 207 students, and 65 missing role) with 1673 school-based contacts (107 staff and 1566 students). The F20/S21 SAR was 2.2% (lower bound, 1.6%; upper bound, 26.7%), and the F21 SAR was 2.8% (lower bound, 2.6%; upper bound, 7.4%). In multivariable analysis, during F20/S21, masking was associated with a lower odds of transmission compared with not masking (odds radio [OR], 0.12; 95% CI, 0.04-0.40; P < .001). In F21, classroom exposure vs out-of-classroom exposure was associated with increased odds of transmission (OR, 2.47; 95% CI, 1.07-5.66; P = .02); a fully vaccinated vs unvaccinated contact was associated with a lower odds of transmission (OR, 0.04; 95% CI, 0.00-0.62; P < .001). In both periods, a higher SVI was associated with a greater odds of transmission.

Conclusions and Relevance

In this study of Massachusetts schools, the SAR for SARS-CoV-2 among school-based contacts was low during 2 periods, and factors associated with transmission risk varied over time. These findings suggest that ongoing surveillance efforts may be essential to ensure that both targeted resources and mitigation practices remain optimal and relevant for disease prevention.

Predictors of student mask mandate policies in United States school districts during the COVID-19 pandemic

Introduction

Although factors such as urbanicity, population demographics, and political affiliation have been linked with COVID-19 masking behavior and policy in community settings, little work has investigated factors associated with school mask policies. We sought to characterize United States state and school district student COVID-19 masking policies during the 2021-22 school year and determine predictors of these mandates at four time points, including before and after federal guidance relaxed school mask recommendations in February 2022.

Methods

Student mask policies for US states and the District of Columbia, as well as a sample of 56 districts were categorized as prohibited, recommended, or required in September 2021, November 2021, January 2022, and March 2022 based on the Johns Hopkins eSchool+ Initiative School Reopening Tracker. Changes in policies over time were characterized. Generalized estimating equations and logistic regression were used to evaluate whether political affiliation of governor, urbanicity, economic disadvantage, and race/ethnic composition of district students, and county-level COVID-19 incidence predicted the presence of a district mask mandate at any time point and at all four time points.

Results

State and district policies changed over time. Districts that implemented student mandates at any point were more likely to be in states with Democratic governors (AOR: 5.52; 95% CI: 2.23, 13.64) or in non-rural areas (AOR: 8.20; 95% CI: 2.63, 25.51). Districts that retained mask mandates at all four time points were more likely to have Democratic governors (AOR: 5.39; 95% CI: 2.69, 10.82) and serve a smaller proportion of economically disadvantaged students (AOR: 0.97; 95% CI: 0.95, 0.99). Districts serving a larger proportion of students from minoritized racial/ethnic groups were more likely to have mask mandates at any or all timepoints. Notably, county-level COVID-19 prevalence was not related to the presence of a mask mandate at any or all time points. By March 2022, no factors were significantly associated with district mask policy.

Discussion

Political, geographic, and demographic characteristics predicted the likelihood of student mask mandates in the 2021-22 school year. Public health promotion messages and policy must account for variation in these factors, potentially through centralized and consistent messaging and unbiased, trustworthy communication.

Policies on children and schools during the SARS-CoV-2 pandemic in Western Europe

During the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mitigation policies for children have been a topic of considerable uncertainty and debate. Although some children have co-morbidities which increase their risk for severe coronavirus disease (COVID-19), and complications such as multisystem inflammatory syndrome and long COVID, most children only get mild COVID-19. On the other hand, consistent evidence shows that mass mitigation measures had enormous adverse impacts on children. A central question can thus be posed: What amount of mitigation should children bear, in response to a disease that is disproportionally affecting older people? In this review, we analyze the distinct child versus adult epidemiology, policies, mitigation trade-offs and outcomes in children in Western Europe. The highly heterogenous European policies applied to children compared to adults did not lead to significant measurable differences in outcomes. Remarkably, the relative epidemiological importance of transmission from school-age children to other age groups remains uncertain, with current evidence suggesting that schools often follow, rather than lead, community transmission. Important learning points for future pandemics are summarized.

School-Based Mandatory Masking Policies and Absenteeism in Ottawa, Canada, in 2022

This cohort study assesses the association between school-based mandatory masking policies and educational disruption in Ottawa, Canada, during the COVID-19 pandemic.

Looking under the lamp-post: quantifying the performance of contact tracing in the United States during the SARS-CoV-2 pandemic

Contact tracing forms a crucial part of the public-health toolbox in mitigating and understanding emergent pathogens and nascent disease outbreaks. Contact tracing in the United States was conducted during the pre-Omicron phase of the ongoing COVID-19 pandemic. This tracing relied on voluntary reporting and responses, often using rapid antigen tests (with a high false negative rate) due to lack of accessibility to PCR tests. These limitations, combined with SARS-CoV-2's propensity for asymptomatic transmission, raise the question "how reliable was contact tracing for COVID-19 in the United States"? We answered this question using a Markov model to examine the efficiency with which transmission could be detected based on the design and response rates of contact tracing studies in the United States. Our results suggest that contact tracing protocols in the U.S. are unlikely to have identified more than 1.65% (95% uncertainty interval: 1.62%-1.68%) of transmission events with PCR testing and 0.88% (95% uncertainty interval 0.86%-0.89%) with rapid antigen testing. When considering an optimal scenario, based on compliance rates in East Asia with PCR testing, this increases to 62.7% (95% uncertainty interval: 62.6%-62.8%). These findings highlight the limitations in interpretability for studies of SARS-CoV-2 disease spread based on U.S. contact tracing and underscore the vulnerability of the population to future disease outbreaks, for SARS-CoV-2 and other pathogens.

The effect of activity and face masks on exhaled particles in children

Importance

Despite the high burden of respiratory infections among children, the production of exhaled particles during common activities and the efficacy of face masks in children have not been sufficiently studied.

Objective

To determine the effect of type of activity and mask usage on exhaled particle production in children.

Methods

Healthy children were asked to perform activities that ranged in intensity (breathing quietly, speaking, singing, coughing, and sneezing) while wearing no mask, a cloth mask, or a surgical mask. The concentration and size of exhaled particles were assessed during each activity.

Results

Twenty-three children were enrolled in the study. Average exhaled particle concentration increased by intensity of activity, with the lowest particle concentration during tidal breathing (1.285 particles/cm3 [95% CI 0.943, 1.627]) and highest particle concentration during sneezing (5.183 particles/cm3 [95% CI 1.911, 8.455]). High-intensity activities were associated with an increase primarily in the respirable size (≤ 5 µm) particle fraction. Surgical and cloth masks were associated with lower average particle concentration compared to no mask (P = 0.026 for sneezing). Surgical masks outperformed cloth masks across all activities, especially within the respirable size fraction. In a multivariable linear regression model, we observed significant effect modification of activity by age and by mask type.

Interpretation

Similar to adults, children produce exhaled particles that vary in size and concentration across a range of activities. Production of respirable size fraction particles (≤ 5 µm), the dominant mode of transmission of many respiratory viruses, increases significantly with coughing and sneezing and is most effectively reduced by wearing surgical face masks.

State Variation in Neighborhood COVID-19 Burden: Findings from the COVID Neighborhood Project

A lack of fine, spatially-resolute case data for the U.S. has prevented the examination of how COVID-19 burden has been distributed across neighborhoods, a known geographic unit of both risk and resilience, and is hampering efforts to identify and mitigate the long-term fallout from COVID-19 in vulnerable communities. Using spatially-referenced data from 21 states at the ZIP code or census tract level, we documented how the distribution of COVID-19 at the neighborhood-level varies significantly within and between states. The median case count per neighborhood (IQR) in Oregon was 3,608 (2,487) per 100,000 population, indicating a more homogenous distribution of COVID-19 burden, whereas in Vermont the median case count per neighborhood (IQR) was 8,142 (11,031) per 100,000. We also found that the association between features of the neighborhood social environment and burden varied in magnitude and direction by state. Our findings underscore the importance of local contexts when addressing the long-term social and economic fallout communities will face from COVID-19.

Nonpharmaceutical interventions for managing SARS-CoV-2

PURPOSE OF REVIEW

Initial response strategies to the COVID-19 pandemic were heavily reliant on nonpharmaceutical interventions (NPIs), a set of measures implemented to slow or even stop the spread of infection. Here, we reviewed key measures used during the COVID-19 pandemic.

RECENT FINDINGS

Some NPIs were successful in reducing the transmission of SARS-CoV-2. Personal protective measures such as face masks were widely used, and likely had some effect on transmission. The development and production of rapid antigen tests allowed self-diagnosis in the community, informing isolation and quarantine measures. Community-wide measures such as school closures, workplace closures and complete stay-at-home orders were able to reduce contacts and prevent transmission. They were widely used in the pandemic and contributed to reduce transmission in the community; however, there were also negative unintended consequences in the society and economy.

SUMMARY

NPIs slowed the spread of SARS-CoV-2 and are essential for pandemic preparedness and response. Understanding which measures are more effective at reducing transmission with lower costs is imperative.

Face mask recommendations in schools did not impact COVID-19 incidence among 10-12-year-olds in Finland - joinpoint regression analysis

BACKGROUND

In autumn 2021 in Finland, a recommendation to use face masks was implemented nationwide in schools for pupils ages 12 years and above. While national guidelines were in form of recommendations, cities implemented mandatory masking in schools. Some cities extended this mandate for younger pupils as well. Our aim was to compare COVID-19 incidence among 10-12-year-olds between cities with different recommendations on the use of face masks in schools.

METHODS

COVID-19 case numbers, defined as positive laboratory verified SARS-CoV-2 test results, were obtained from the National Infectious Disease Registry (NIDR) of the Finnish Institute for Health and Welfare. Helsinki, Turku and Tampere were selected for comparison since the baseline COVID-19 incidence in the cities had been similar in August and September 2021. Helsinki and Tampere implemented the national recommendation on face mask use at schools, while Turku extended this to include those 10 years old and above, starting from the beginning of semester in early August. Age groups of 7-9-year-olds, 10-12-year-olds and 30-49-year-olds were included in the statistical analysis and moving averages of 14-day incidences per 100 000 inhabitants were used as a dependent variable. Joinpoint regression was used to estimate average percent changes (APC) and average daily percent changes (ADPC) in the 14-day incidences. Differences in the ADPC values between the cities were compared in one-month periods. We also calculated cumulative incidences from the beginning of August to the end of November in the cities by age group.

RESULTS

In August, the ADPC was highest in Turku (3.9) and lowest in Tampere (2.0), while in September, the ADPC was highest in Turku (-0.3) and lowest in Helsinki (-3.2) among 10-12-year-olds. In October, the ADPC was highest in Helsinki (2.1) and lowest in Turku (-0.2) and in November, the ADPC was highest in Turku (4.1) and lowest in Tampere (-0.5) among 10-12-year-olds. We also calculated cumulative incidences from the beginning of August to the end of November in the cities by age groups of 7-9 years, 10-12 years, and 30-49 years. The cumulative incidence was highest in Turku in all age groups and lowest in Tampere.

CONCLUSIONS

According to our analysis, no additional effect was gained from mandating face masks, based on comparisons between the cities and between the age groups of the unvaccinated children (10-12 years versus 7-9 years).

Update on Covid-19: vaccines, timing of transplant after COVID-19 infection and use of positive donors

PURPOSE OF REVIEW

SARS-CoV-2 resulted in a global pandemic that had a chilling effect on transplantation early in the pandemic and continues to result in significant morbidity and mortality of transplant recipients. Over the past 2.5 years, our understanding of the clinical utility of vaccination and mAbs to prevent COVID-19 in solid organ transplant (SOT) recipients has been studied. Likewise, approach to donors and candidates with SARS-CoV-2 has been better understood. This review will attempt to summarize our current understanding of these important COVID-19 topics.

RECENT FINDINGS

Vaccination against SARS-CoV-2 is effective in reducing the risk of severe disease and death among transplant patients. Unfortunately, humoral and, to a lesser extent, cellular immune response to existing COVID-19 vaccines is reduced in SOT recipients compared with healthy controls. Additional doses of vaccine are required to optimize protection of this population and still may be insufficient in those who are highly immunosuppressed, those receiving belatacept, rituximab and other B-cell active mAbs. Until recently, mAbs were options for the prevention of SARS-CoV-2 but are markedly less effective with recent omicron variants. SARS-CoV-2-infected donors can generally be used for nonlung, nonsmall bowel transplants unless they have died of acute severe COVID-19 or COVID-19-associated clotting disorders.

SUMMARY

Our transplant recipients require a three-dose mRNA or adenovirus-vector and one dose of mRNA vaccine to be optimally protected initially; they then need to receive a bivalent booster 2+ months after completing their initial series. Most nonlung, nonsmall bowel donors with SARS-CoV-2 can be utilized as organ donors.

School closures during COVID-19: an overview of systematic reviews

OBJECTIVES

To assess the benefits and drawbacks of school closures and in-school mitigations during the COVID-19 pandemic.

DESIGN

Overview of systematic reviews (SRs).

SEARCH METHODS

We searched six databases and additional resources on 29 July 2022: MEDLINE, Embase, Google Scholar, Cochrane Library, COVID-END inventory of evidence synthesis, and Epistemonikos.

ELIGIBILITY CRITERIA

We selected SRs written in English that answered at least one of four specific questions concerning the efficacy and drawbacks of school closures. Their primary studies were conducted in primary and secondary schools, including pupils aged 5-18. Interventions included school closures or mitigations (such as mask usage) introduced in schools.

DATA COLLECTION AND ANALYSIS

We used AMSTAR 2 to assess confidence in the included SRs, and GRADE was used to assess certainty of evidence. We performed a narrative synthesis of the results, prioritising higher-quality SRs, those which performed GRADE assessments and those with more unique primary studies. We also assessed the overlap between primary studies included in the SRs.

MAIN OUTCOME MEASURES

Our framework for summarising outcome data was guided by the following questions: (1) What is the impact of school closures on COVID-19 transmission, morbidity or mortality in the community? (2) What is the impact of COVID-19 school closures on mental health (eg, anxiety), physical health (eg, obesity, domestic violence, sleep) and learning/achievement of primary and secondary pupils? (3) What is the impact of mitigations in schools on COVID-19 transmission, morbidity or mortality in the community? and (4) What is the impact of COVID-19 mitigations in schools on mental health, physical health and learning/achievement of primary and secondary pupils?

RESULTS

We identified 578 reports, 26 of which were included. One SR was of high confidence, 0 moderate, 10 low and 15 critically low confidence. We identified 132 unique primary studies on the effects of school closures on transmission/morbidity/mortality, 123 on learning, 164 on mental health, 22 on physical health, 16 on sleep, 7 on domestic violence and 69 on effects of in-school mitigations on transmission/morbidity/mortality.Both school closures and in-school mitigations were associated with reduced COVID-19 transmission, morbidity and mortality in the community. School closures were also associated with reduced learning, increased anxiety and increased obesity in pupils. We found no SRs that assessed potential drawbacks of in-school mitigations on pupils. The certainty of evidence according to GRADE was mostly very low.

CONCLUSIONS

School closures during COVID-19 had both positive and negative impacts. We found a large number of SRs and primary studies. However, confidence in the SRs was mostly low to very low, and the certainty of evidence was also mostly very low. We found no SRs assessing the potential drawbacks of in-school mitigations on children, which could be addressed moving forward. This overview provides evidence that could inform policy makers on school closures during future potential waves of COVID-19.

COVID-19 Policies, Pandemic Disruptions, and Changes in Child Mental Health and Sleep in the United States

IMPORTANCE

The adverse effects of COVID-19 containment policies disrupting child mental health and sleep have been debated. However, few current estimates correct biases of these potential effects.

OBJECTIVES

To determine whether financial and school disruptions related to COVID-19 containment policies and unemployment rates were separately associated with perceived stress, sadness, positive affect, COVID-19-related worry, and sleep.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was based on the Adolescent Brain Cognitive Development Study COVID-19 Rapid Response Release and used data collected 5 times between May and December 2020. Indexes of state-level COVID-19 policies (restrictive, supportive) and county-level unemployment rates were used to plausibly address confounding biases through 2-stage limited information maximum likelihood instrumental variables analyses. Data from 6030 US children aged 10 to 13 years were included. Data analysis was conducted from May 2021 to January 2023.

EXPOSURES

Policy-induced financial disruptions (lost wages or work due to COVID-19 economic impact); policy-induced school disruptions (switches to online or partial in-person schooling).

MAIN OUTCOMES AND MEASURES

Perceived stress scale, National Institutes of Health (NIH)-Toolbox sadness, NIH-Toolbox positive affect, COVID-19-related worry, and sleep (latency, inertia, duration).

RESULTS

In this study, 6030 children were included in the mental health sample (weighted median [IQR] age, 13 [12-13] years; 2947 [48.9%] females, 273 [4.5%] Asian children, 461 [7.6%] Black children, 1167 [19.4%] Hispanic children, 3783 [62.7%] White children, 347 [5.7%] children of other or multiracial ethnicity). After imputing missing data, experiencing financial disruption was associated with a 205.2% [95% CI, 52.9%-509.0%] increase in stress, a 112.1% [95% CI, 22.2%-268.1%] increase in sadness, 32.9% [95% CI, 3.5%-53.4%] decrease in positive affect, and a 73.9 [95% CI, 13.2-134.7] percentage-point increase in moderate-to-extreme COVID-19-related worry. There was no association between school disruption and mental health. Neither school disruption nor financial disruption were associated with sleep.

CONCLUSIONS AND RELEVANCE

To our knowledge, this study presents the first bias-corrected estimates linking COVID-19 policy-related financial disruptions with child mental health outcomes. School disruptions did not affect indices of children's mental health. These findings suggest public policy should consider the economic impact on families due to pandemic containment measures, in part to protect child mental health until vaccines and antiviral drugs become available.

SARS-CoV-2 infection characteristics among students and staff in a large high school COVID-19 outbreak and secondary transmission in households

Background

SARS-CoV-2 clinical presentation is associated with the patients' age group. Overall, young individuals present higher proportions of asymptomatic or mild COVID-19 infection, compared to adults. Data on secondary COVID-19 transmission in households, according to the cases' age group, are accumulating.

Methods

We performed a follow-up cohort study including all COVID-19 real-time polymerase chain reaction (RT-PCR)-confirmed cases (adolescent students and school staff) diagnosed in an epidemiological investigation of a large high school outbreak. We compared the adolescent and adult groups regarding clinical symptoms, time to negative COVID-19 RT-PCR tests, and infection transmission in households.

Results

The study population included 817 persons. The confirmed COVID-19 RT-PCR outbreak cases (n = 178) were followed (students aged 12-19 years, median age 14 years, n = 153, school staff aged 24-67 years, median age 39 years, n = 25) and the cases' household close contacts (n = 639) were tested. The adolescents had lower symptomatic infection rates, shorter time to negative COVID-19 RT-PCR tests, and lower transmission rates to household members, compared to the adults. The general transmission rate among household contacts was 13.5%, (86/639) ranging from 8.6% in asymptomatic students' contacts to 27.3% in symptomatic staff contacts. COVID-19 transmission rates were significantly higher in contacts of symptomatic cases compared to asymptomatic cases (odds ratio: 2.06, 95% CI 1.26-3.4) and higher in adults compared to adolescents (odds ratio: 2.69, 95% CI 1.43-4.89).

Conclusions

Adolescents and adults diagnosed in an outbreak investigation differ as to COVID-19 clinical presentation and transmission. As adolescents may show mild or no symptoms, COVID-19 prevention in school settings is challenging. Implementing nonpharmaceutical measures and promoting vaccination programs in eligible staff and students should be considered.

Impact of COVID-19 on pediatric surgery cancellations: A retrospective study

BACKGROUND

Prevalence trends and reasons for pediatric surgery cancellation in Japan during the coronavirus disease 2019 (COVID-19) pandemic have not previously been reported. This study aimed to compare the prevalence and reasons for cancellation of pediatric surgeries in Japan before and during the COVID-19 pandemic.

METHODS

This single-center retrospective cohort study reviewed the reasons for surgery cancellations scheduled for patients aged <18 years between the prepandemic period (September 2017-December 2019) and the COVID-19 pandemic period (January 2020-April 2022). The cancellation reasons were classified into four major categories: medical, surgical, patient-related, and administrative.

RESULTS

Of the 3395 and 3455 surgeries scheduled before and during the COVID-19 pandemic, 305 (9.0%) and 319 (9.2%) surgeries were canceled (p = 0.737), respectively. The proportion of cancellations due to infections or fever in medical reasons decreased from 67.9% to 56.1% (p = 0.003) and that due to patient-related reasons increased from 6.6% to 15.1% (p = 0.001). Further, the proportion of cancellations due to staff shortages in staff administrative reasons increased from 0.3% to 3.1% (p = 0.011). There was no significant difference in the proportion of surgeries canceled due to surgical reasons between the two periods.

CONCLUSIONS

The proportion of cancellations due to infections or fever decreased during the COVID-19 pandemic, while that due to staff shortages increased. Infection prevention is an important measure to address the staff shortages. Implementation of national or regional policies and additional strategic interventions may be required to prepare for disasters like the COVID-19 pandemic.

The next 'pandemic playbook' needs to prioritize the needs of children-and a clear roadmap for opening schools

The national influenza pandemic response plan includes short-term school closures as an infection mitigation measure, based on modeling data regarding the role of pediatric populations and schools as drivers of disease spread. Modeled estimates regarding the role of children and their in-school contacts as drivers of community transmission of endemic respiratory viruses were used in part to justify prolonged school closures throughout the United States. However, disease transmission models extrapolated from endemic pathogens to novel ones may underestimate the degree to which spread is driven by population immunity and overestimate the impact of school closures as a means of reducing child contacts, particularly in the longer-term. These errors, in turn, may have caused incorrect estimations about the potential benefits of closing schools on a society level while simultaneously failing to account for the significant harms of long-term educational disruption. Pandemic response plans need to be updated to include nuances regarding drivers of transmission such as pathogen type, population immunity, and contact patterns, and disease severity in different groups. Expected duration of impact also needs to be considered, recognizing that effectiveness of different interventions, particularly those focused on limiting social interactions, are short-lived. Additionally, future iterations should include risk-benefit assessments. Interventions that are particularly harmful to certain groups, such as school closures are on children, should be de-emphasized and time limited. Finally, pandemic responses should include ongoing and continuous policy re-evaluation and should include a clear plan for de-implementation and de-escalation.

Principles to Guide the US Toward Better Health for All

This JAMA Forum discusses ways to work toward health equity in the US, suggests structural changes that could be implemented to remedy historical underinvestments in health, and provides ideas for how to gain public trust and buy-in for policies to achieve these goals.