COVID-19 Testing to Sustain In-Person Instruction and Extracurricular Activities in High Schools - Utah, November 2020-March 2021

A longitudinal analysis of COVID-19 prevention strategies implemented among US K-12 public schools during the 2021-2022 school year

PURPOSE

Examine how school-based COVID-19 prevention strategy implementation varied over time, including by local characteristics.

METHODS

School administrators (n = 335) from a nationally representative sample of K-12 public schools completed four surveys assessing COVID-19 prevention strategies at two-month intervals between October 2021 and June 2022. We calculated weighted prevalence estimates by survey wave. Generalized estimating equations (GEE) were used to model longitudinal changes in strategy implementation, accounting for school and county covariates.

RESULTS

Opening doors/windows, daily cleaning, and diagnostic testing were reported by ≥ 50 % of schools at each survey wave. Several strategies were consistently implemented across the 2021-2022 school year (i.e., daily cleaning, opening doors and windows, diagnostic testing) while other strategies increased initially and then declined (i.e., contact tracing, screening testing, on-campus vaccination) or declined consistently throughout the school year (i.e., mask requirement, classroom distancing, quarantine). Although longitudinal changes in strategy implementation did not vary by school characteristics, strategy implementation varied by urban-rural classification and school level throughout the school year.

CONCLUSIONS

Strategies that were consistently implemented throughout the school year were also reported by a majority of schools, speaking toward their feasibility for school-based infection control and prevention and potential utility in future public health emergencies.

SARS-CoV-2 Test-to-Stay in Daycare

BACKGROUND AND OBJECTIVES

Test-to-stay concepts apply serial testing of children in daycare after exposure to SARS-CoV-2 without use of quarantine. This study aims to assess the safety of a test-to-stay screening in daycare facilities.

METHODS

714 daycare facilities and approximately 50 000 children ≤6 years in Cologne, Germany participated in a SARS-CoV-2 Pool-polymerase chain reaction (PCR) screening from March 2021 to April 2022. The screening initially comprised post-exposure quarantine and was adapted to a test-to-stay approach during its course. To assess safety of the test-to-stay approach, we explored potential changes in frequencies of infections among children after the adaptation to the test-to-stay approach by applying regression discontinuity in time (RDiT) analyses. To this end, PCR-test data were linked with routinely collected data on reported infections in children and analyzed using ordinary least squares regressions.

RESULTS

219 885 Pool-PCRs and 352 305 Single-PCRs were performed. 6440 (2.93%) Pool-PCRs tested positive, and 17 208 infections in children were reported. We estimated that during a period of 30 weeks, the test-to-stay concept avoided between 7 and 20 days of quarantine per eligible daycare child. RDiT revealed a 26% reduction (Exp. Coef: 0.74, confidence interval 0.52-1.06) in infection frequency among children and indicated no significant increase attributable to the test-to-stay approach. This result was not sensitive to adjustments for 7-day incidence, season, SARS-CoV-2 variant, and socioeconomic status.

CONCLUSIONS

Our analyses provide evidence that suggest safety of the test-to-stay approach compared with quarantine measures. This approach offers a promising option to avoid use of quarantine after exposure to respiratory pathogens in daycare settings.

Flexible Bayesian inference on partially observed epidemics

Individual-based models of contagious processes are useful for predicting epidemic trajectories and informing intervention strategies. In such models, the incorporation of contact network information can capture the non-randomness and heterogeneity of realistic contact dynamics. In this article, we consider Bayesian inference on the spreading parameters of an SIR contagion on a known, static network, where information regarding individual disease status is known only from a series of tests (positive or negative disease status). When the contagion model is complex or information such as infection and removal times is missing, the posterior distribution can be difficult to sample from. Previous work has considered the use of Approximate Bayesian Computation (ABC), which allows for simulation-based Bayesian inference on complex models. However, ABC methods usually require the user to select reasonable summary statistics. Here, we consider an inference scheme based on the Mixture Density Network compressed ABC, which minimizes the expected posterior entropy in order to learn informative summary statistics. This allows us to conduct Bayesian inference on the parameters of a partially observed contagious process while also circumventing the need for manual summary statistic selection. This methodology can be extended to incorporate additional simulation complexities, including behavioural change after positive tests or false test results.

COVID-19 Related Facilitators and Barriers to In-Person Learning for Children With Intellectual and Development Disabilities: A Follow-Up

BACKGROUND

Students with intellectual and developmental disabilities (IDD) and the staff who support them were largely in-person during the 2021-2022 school year, despite their continued vulnerability to infection with SARS-CoV-2. This qualitative study aimed to understand continued perceptions of weekly SARS-CoV-2 screening testing of students and staff amidst increased availability of vaccinations.

METHODS

Twenty-three focus groups were held with school staff and parents of children with IDD to examine the perceptions of COVID-19 during the 2021-2022 school year. Responses were analyzed using a directed thematic content analysis approach.

RESULTS

Four principal themes were identified: strengths and opportunities of school- and district-level mitigation policies; experience at school with the return to in-person learning; facilitators and barriers to participation in SARS-CoV-2 screening testing; and perceptions of SARS-CoV-2 testing in light of vaccine availability.

IMPLICATIONS FOR SCHOOL HEALTH POLICY, PRACTICE, AND EQUITY

Despite the increased availability of vaccines, school staff and families agreed that saliva-based SARS-CoV-2 screening testing helped increase comfort with in-person learning as long as the virus was present in the community.

CONCLUSION

To keep children with IDD in school during the pandemic, families found SARS-CoV-2 screening testing important. Clearly communicating school policies and mitigation strategies facilitated peace of mind and confidence in the school district.

Previous Infection and Effectiveness of COVID-19 Vaccination in Middle- and High-School Students

BACKGROUND AND OBJECTIVES

Understanding the real-world impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mitigation measures, particularly vaccination, in children and adolescents in congregate settings remains important. We evaluated protection against SARS-CoV-2 infection using school-based testing data.

METHODS

Using data from Utah middle- and high-school students participating in school-wide antigen testing in January 2022 during omicron (BA.1) variant predominance, log binomial models were fit to estimate the protection of previous SARS-CoV-2 infection and coronavirus disease 2019 vaccination against SARS-CoV-2 infection.

RESULTS

Among 17 910 students, median age was 16 years (range: 12-19), 16.7% had documented previous SARS-CoV-2 infection; 55.6% received 2 vaccine doses with 211 median days since the second dose; and 8.6% of students aged 16 to 19 years received 3 vaccine doses with 21 median days since the third dose. Protection from previous infection alone was 35.9% (95% confidence interval [CI]: 12.9%-52.8%) and 23.8% (95% CI: 2.1%-40.7%) for students aged 12 to 15 and 16 to 19 years, respectively. Protection from 2-dose hybrid immunity (previous SARS-CoV-2 infection and vaccination) with <180 days since the second dose was 58.7% (95% CI: 33.2%-74.4%) for students aged 12 to 15 and 54.7% (95% CI: 31.0%-70.3%) for students aged 16 to 19 years. Protection was highest (70.0%, 95% CI: 42.3%-84.5%) among students with 3-dose hybrid immunity, although confidence intervals overlap with 2-dose vaccination.

CONCLUSIONS

The estimated protection against infection was strongest for those with hybrid immunity from previous infection and recent vaccination with a third dose.

Predictors of Willingness to Participate in COVID-19 Screening Testing from a Pilot School Survey in the United States

BACKGROUND

COVID-19 screening testing (ST) can detect asymptomatic or pre-symptomatic cases, allowing for prompt identification of cases and close contacts. This study examined parents' and school staffs' knowledge and attitudes toward to a pilot school-based ST program in a school district in southern Arizona.

METHODS

In May 2021, online surveys to parents and school staff were administered to examine attitudes toward ST and impacts of the COVID-19 pandemic. Unweighted percent estimates were calculated, and bivariate differences were examined by demographics. Associations were assessed using chi-square tests and logistic regression.

RESULTS

The survey had response rates of 10% (606/6085) and 22% (187/849) among parents and staff, respectively. Approximately one-third of responding parents (35%) would or already allow their child to participate in school-based ST, 37% would not participate; 28% were unsure. Among responding staff, 46% would or already participate in ST, 33% would not; 21% were unsure. The top concern (38%) among responding staff was taking job-related leave if testing positive.

CONCLUSION

Schools work to balance the needs of students, families, and staff by implementing supportive and flexible policies and practices founded on buy-in and acceptance from their communities.

At-Home Versus Onsite COVID-19 School-based Testing: A Randomized Noninferiority Trial

OBJECTIVES

Equitable access to coronavirus 2019 (COVID-19) screening is important to reduce transmission and maintain in-person learning for middle school communities, particularly in disadvantaged schools. Rapid antigen testing, and at-home testing in particular, could offer substantial advantages over onsite testing from a school district's perspective, but it is unknown if engagement in at-home testing can be initiated and sustained. We hypothesized that an at-home COVID-19 school testing program would be noninferior to an onsite school COVID-19 testing program with regard to school participation rates and adherence to a weekly screening testing schedule.

METHODS

We enrolled 3 middle schools within a large, predominantly Latinx-serving, independent school district into a noninferiority trial from October 2021 to March 2022. Two schools were randomized to onsite and 1 school to at-home COVID-19 testing programs. All students and staff were eligible to participate.

RESULTS

Over the 21-week trial, at-home weekly screening testing participation rates were not inferior to onsite testing. Similarly, adherence to the weekly testing schedule was not inferior in the at-home arm. Participants in the at-home testing arm were able to test more consistently during and before returning from school breaks than those in the onsite arm.

CONCLUSIONS

Results support the noninferiority of at-home testing versus onsite testing both in terms of participation in testing and adherence to weekly testing. Implementation of at-home COVID-19 screening testing should be part of schools' routine COVID-19 prevention efforts nationwide; however, adequate support is essential to ensure participation and persistence in regular at-home testing.

Preliminary Reach of an Information Technology Approach to Support COVID-19 Testing in Schools

OBJECTIVES

SCALE-UP Counts tests population health management interventions to promote coronavirus disease 2019 (COVID-19) testing in kindergarten through 12th-grade schools that serve populations that have been historically marginalized.

METHODS

Within 6 participating schools, we identified 3506 unique parents/guardians who served as the primary contact for at least 1 student. Participants were randomized to text messaging (TM), text messaging + health navigation (HN) (TM + HN), or usual care. Bidirectional texts provided COVID-19 symptom screening, along with guidance on obtaining and using tests as appropriate. If parents/guardians in the TM + HN group were advised to test their child but either did not test or did not respond to texts, they were called by a trained health navigator to address barriers.

RESULTS

Participating schools served a student population that was 32.9% non-white and 15.4% Hispanic, with 49.6% of students eligible to receive free lunches. Overall, 98.8% of parents/guardians had a valid cell phone, of which 3.8% opted out. Among the 2323 parents/guardians included in the intervention, 79.6% (n = 1849) were randomized to receive TM, and 19.1% (n = 354) engaged with TM (ie, responded to at least 1 message). Within the TM + HN group (40.1%, n = 932), 1.3% (n = 12) qualified for HN at least once, of which 41.7% (n = 5) talked to a health navigator.

CONCLUSIONS

TM and HN are feasible ways to reach parents/guardians of kindergarten through 12th-grade students to provide COVID-19 screening messages. Strategies to improve engagement may strengthen the impact of the intervention.

A Multi-Study Synthesis of Facilitators and Barriers to SARS-CoV-2 Testing Enrollment in School Settings

OBJECTIVES

Understanding the motivators and barriers to testing enrollment from different stakeholder perspectives is essential to increasing participation in school-based testing programs, particularly among underserved populations. This multistudy analysis aimed to identify facilitators and barriers to enrollment in school-based testing for coronavirus disease 2019 (COVID-19).

METHODS

Four independent studies collected and analyzed qualitative data from study participants regarding: (1) motivators, benefits, and/or reasons for enrolling and/or participating in COVID-19 testing in schools; and/or (2) concerns, barriers, and/or negative outcomes related to COVID-19 testing in schools. Study authors conducted a retrospective review of findings from the independent studies to identify themes related to testing motivators and concerns that emerged across the studies.

RESULTS

The analysis identified 10 distinct themes regarding the perceived motivators of COVID-19 testing in schools and 15 distinct themes regarding concerns and barriers to COVID-19 testing in schools. Common motivators across multiple studies included convenience of testing in school and the desire to keep self and others safe from COVID-19. Concerns about the implications of receiving a positive test result was a barrier identified by multiple studies.

CONCLUSIONS

Themes from 4 independent studies revealed insights about the motivations and barriers to enrolling and participating in COVID-19 testing programs in kindergarten through 12th grade school settings. Study findings can be used to improve enrollment and participation in new and existing school-based testing programs to reduce transmission of COVID-19 and other infectious diseases in schools.

Evaluation of a COVID-19 rapid antigen testing program among student athletes in a public high school district

PURPOSE

The purpose of this study is to evaluate a COVID-19 rapid antigen testing program among high school athletes through testing data and qualitative analysis from key stakeholders.

METHODS

Testing data was obtained by the partnering school district. Testing staff, coaches, and parents participated in a focus group using a semi-structured focus group guide. Transcripts were analyzed using a grounded theory approach to produce the themes of the study.

RESULTS

Rapid antigen tests quickly identified a COVID-19-positive student athlete, which allowed for quick isolation and zero transmission to teammates. Focus groups with parents, testing staff, and coaches indicated the testing program improved perceived safety and demonstrated the ability for school staff to implement a widespread COVID-19 screening program with minimal training.

CONCLUSIONS

As schools continue to respond to various waves of COVID-19 infections, targeted testing for high-risk activities in school settings such as sports programs may help prevent school outbreaks during times of high community transmission rates. This evaluation adds to a body of literature that will aid schools and policy makers in their decision on how to best keep student athletes and school communities safe for future waves of COVID-19 infection and other pandemics.

Increases in CLIA-Waived Testing Sites Since the Start of the COVID-19 Pandemic

The number of testing sites receiving their first Certificate of Waiver (CoW) under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) increased significantly after the start of the COVID-19 pandemic. We compared the first-time CoWs in 2020-2021 to those in 2018-2019. The total number of first-time CoWs during 2020-2021 was more than twice what it was in 2018-2019, corresponding to population testing needs during the COVID-19 pandemic, especially in assisted living facility, pharmacy, physician office, and school/student health service settings. This study highlighted the need to strengthen clinical testing strategies to be better prepared for future public health emergencies.

COVID-19 Testing in Schools: Perspectives of School Administrators, Teachers, Parents, and Students in Southern California

BACKGROUND

School-based COVID-19 testing is a potential strategy to facilitate the safe reopening of schools that have been closed due to the pandemic. This qualitative study assessed attitudes toward this strategy among four groups of stakeholders: school administrators, teachers, parents, and high school students.

METHODS

Focus groups and interviews were conducted in Los Angeles from December 2020 to January 2021 when schools were closed due to the high level of COVID transmission in the community.

RESULTS

Findings indicated similarities and differences in attitudes toward in-school COVID-19 testing. All groups agreed that frequent in-school COVID-19 testing could increase the actual safety and perceived safety of the school environment. School administrators expressed pessimism about the financial cost and logistics of implementing a testing program. Parents supported frequent testing but expressed concerns about physical discomfort and stigma for students who test positive. Teachers and parents noted that testing would prevent parents from sending sick children to school. Students were in favor of testing because it would allow them to return to in-person school after a difficult year of online learning.

CONCLUSION

In-school COVID-19 testing could be a useful component of school reopening plans and will be accepted by stakeholders if logistical and financial barriers can be surmounted and stigma from positive results can be minimized.

COVID-19 Test Allocation Strategy to Mitigate SARS-CoV-2 Infections across School Districts

In response to COVID-19, schools across the United States closed in early 2020; many did not fully reopen until late 2021. Although regular testing of asymptomatic students, teachers, and staff can reduce transmission risks, few school systems consistently used proactive testing to safeguard return to classrooms. Socioeconomically diverse public school districts might vary testing levels across campuses to ensure fair, effective use of limited resources. We describe a test allocation approach to reduce overall infections and disparities across school districts. Using a model of SARS-CoV-2 transmission in schools fit to data from a large metropolitan school district in Texas, we reduced incidence between the highest and lowest risk schools from a 5.6-fold difference under proportional test allocation to 1.8-fold difference under our optimized test allocation. This approach provides a roadmap to help school districts deploy proactive testing and mitigate risks of future SARS-CoV-2 variants and other pathogen threats.

SARS-CoV-2 Screening Testing Programs for Safe In-person Learning in K-12 Schools

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) screening testing is a recommended mitigation strategy for schools, although few descriptions of program implementation are available.

METHODS

Kindergarten through 12th grade (K-12) students and staff practicing universal masking during the delta and omicron variant waves from five schools in Durham, North Carolina and eight schools in Kansas City, Missouri participated; Durham's program was structured as a public health initiative facilitated by school staff, and Kansas City's as a research study facilitated by a research team. Tests included school-based rapid antigen or polymerase chain reaction testing, at-home rapid antigen testing, and off-site nucleic acid amplification testing.

RESULTS

We performed nearly 5700 screening tests on more than 1600 K-12 school students and staff members. The total cost for the Durham testing program in 5 public charter K-12 schools, each with 500-1000 students, was $246 587 and approximately 752 h per semester; cost per test was $70 and cost per positive result was $7076. The total cost for the Kansas City program in eight public K-12 schools was $292 591 and required approximately 537 h in personnel time for school-based testing; cost per test was $132 and cost per positive result was $4818. SARS-CoV-2 positivity rates were generally lower (0-16.16%) than rates in the community (2.7-36.47%) throughout all testing weeks.

CONCLUSIONS AND RELEVANCE

Voluntary screening testing programs in K-12 schools are costly and rarely detect asymptomatic positive persons, particularly in universally masked settings.

CLINICAL TRIAL REGISTRATION

NCT04831866.

When schools were open for in-person teaching during the COVID-19 pandemic - the nordic experience on control measures and transmission in schools during the delta wave

BACKGROUND

Extensive measures to control spread of SARS-CoV-2 have led to limited access to education for millions of children and adolescents during the COVID-19 pandemic. Education and access to schools is vital for children and adolescents' learning, health, and wellbeing. Based on high vaccine uptake and low incidence levels, the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) decided to start the academic year 2021/22 with schools open for in-person teaching and moderate mitigation measures. We describe trends in SARS-CoV-2 infections and vaccination coverage among students during the first 12 weeks of the fall semester.

METHODS

In this multinational, retrospective, observational study, we have used surveillance and registry data from each of the Nordic countries to describe vaccine uptake (≥12 years), infection incidence (whole population) and transmission of SARS-CoV-2 among students. The study period, week 30 to 41 (Jul 26th - Oct 17th), represents the autumn semester from immediately before school started until fall break. In addition, we collected information on mitigation measures applied by the respective countries.

RESULTS

There were slight variations between the countries regarding existing infection prevention and control (IPC) measures, testing strategies and vaccination start-up among adolescents. All countries had high vaccine uptake in the adult population, while uptake varied more in the younger age groups. Incidence in the school-aged population differed between countries and seemed to be influenced by both vaccine uptake and test activity. Infection clusters among school-aged children were described for Denmark and Norway, and the number of clusters per week reflected the incidence trend of the country. Most events consisted of only 1-2 cases. Larger clusters appeared more frequently in the higher grades in Norway and in lower grades in Denmark.

CONCLUSION

Data from the Nordic countries indicate that vaccination of adults and adolescents, in addition to mitigation measures, enabled full in-person learning. As SARS-CoV-2 infection does not represent a severe medical risk for most children as previously thought, measures targeting this group should be carefully adjusted and kept at a minimum. Our data add to the evidence on incidence and transmission of SARS-CoV-2 among students in schools open for in-person teaching, and may be valuable for decision makers worldwide.

COVID-19 Symptoms and Duration of Rapid Antigen Test Positivity at a Community Testing and Surveillance Site During Pre-Delta, Delta, and Omicron BA.1 Periods

Importance

Characterizing the clinical symptoms and evolution of community-based SARS-CoV-2 infections may inform health practitioners and public health officials in a rapidly changing landscape of population immunity and viral variants.

Objectives

To compare COVID-19 symptoms among people testing positive with a rapid antigen test (RAT) during the Omicron BA.1 variant period (December 1, 2021, to January 30, 2022) with the pre-Delta (January 10 to May 31, 2021) and Delta (June 1 to November 30, 2021) variant periods and to assess the duration of RAT positivity during the Omicron BA.1 surge.

Design, Setting, and Participants

This cross-sectional study was conducted from January 10, 2021, to January 31, 2022, at a walk-up community COVID-19 testing site in San Francisco, California. Participants included children and adults seeking COVID-19 testing with an RAT, regardless of age, vaccine status, or symptoms.

Main Outcomes and Measures

Fisher exact tests or χ2 tests were used to compare COVID-19 symptoms during the Omicron BA.1 period with the pre-Delta and Delta periods for vaccination status and age group. Among people returning for repeated testing during the Omicron period, the proportion with a positive RAT between 4 and 14 days from symptom onset or since first positive test if asymptomatic was estimated.

Results

Among 63 277 persons tested (median [IQR] age, 32 [21-44] years, with 12.0% younger than 12 years; 52.0% women; and 68.5% Latinx), a total of 18 301 people (28.9%) reported symptoms, of whom 4565 (24.9%) tested positive for COVID-19. During the Omicron BA.1 period, 3032 of 7283 symptomatic participants (41.6%) tested positive, and the numbers of these reporting cough and sore throat were higher than during pre-Delta and Delta periods (cough: 2044 [67.4%] vs 546 [51.3%] of 1065 participants, P < .001 for pre-Delta, and 281 [60.0%] of 468 participants, P = .002, for Delta; sore throat: 1316 [43.4%] vs 315 [29.6%] of 1065 participants, P < .001 for pre-Delta, and 136 [29.1%] of 468 participants, P < .001, for Delta). Compared with the 1065 patients with positive test results in the pre-Delta period, congestion among the 3032 with positive results during the Omicron BA.1 period was more common (1177 [38.8%] vs 294 [27.6%] participants, P < .001), and loss of taste or smell (160 [5.3%] vs 183 [17.2%] participants, P < .001) and fever (921 [30.4%] vs 369 [34.7%] participants, P = .01) were less common. In addition, during the Omicron BA.1 period, fever was less common among the people with positive test results who had received a vaccine booster compared with those with positive test results who were unvaccinated (97 [22.5%] of 432 vs 42 [36.2%] of 116 participants, P = .003), and fever and myalgia were less common among participants who had received a booster compared with those with positive results who had received only a primary series (fever: 97 [22.5%] of 432 vs 559 [32.8%] of 1705 participants, P < .001; myalgia: 115 [26.6%] of 432 vs 580 [34.0%] of 1705 participants, P = .003). During the Omicron BA.1 period, 5 days after symptom onset, 507 of 1613 people (31.1%) with COVID-19 stated that their symptoms were similar, and 95 people (5.9%) reported worsening symptoms. Among people testing positive, 80.2% of participants who were symptomatic and retested remained positive 5 days after symptom onset.

Conclusions and Relevance

In this cross-sectional study, COVID-19 upper respiratory tract symptoms were more commonly reported during the Omicron BA.1 period than during the pre-Delta and Delta periods, with differences by vaccination status. Rapid antigen test positivity remained high 5 days after symptom onset, supporting guidelines requiring a negative test to inform the length of the isolation period.

Implementation of Test-to-Stay programming to minimize learning loss in a pre-K-8 school district

Objectives

Determine if a school-based Test-to-Stay (TTS) program designed to minimize learning loss reduced the incidence of COVID-19 in a US primary school district.

Study design

Observational, simple summary analysis of attendance and effectiveness of a TTS program implemented in a California school district.

Methods

Retrospective analysis of nested medical and demographic data. Survival curves were plotted using a cumulative hazard function to compare the probability of infection among close contacts exposed at school at different points of time between participants who participated in TTS versus those who did not participate in TTS. A Cox proportional hazards regression model with time-dependent covariates was used to estimate the association of TTS status with the incidence of SARS-CoV-2 infection.

Results

Univariate Cox regression analysis revealed that after adjustment, enrollment in TTS was negatively correlated with the risk of SARS-CoV-2 infection (hazard ratio 0.096; 95% confidence interval [CI], 0.024–0.390; P < 0.001).

Conclusions

TTS is an effective component of a layered protection strategy to prevent COVID-19 transmission in schools and communities, while minimizing the loss of in-person instruction in primary schools.

Prevalence of SARS-CoV-2 antibodies among university athletic club members: A cross-sectional survey

School-based coronavirus disease 2019 (COVID-19) testing is an important part of a comprehensive prevention strategy in public health. To assess the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in a university athletic club community with repeated occurrences of SARS-CoV-2 infections, we conducted a cross-sectional survey for asymptomatic antibody prevalence using a SARS-CoV-2 rapid antibody test kit. On January 26, 2021 we administered questionnaires to determine their history of contact with infected individuals and took blood samples from 129 undergraduates. The prevalence of SARS-CoV-2 antibodies among the subjects was 3.9%. Only 6.2% of the participants reported close contact with infected individuals. In this study, we clarified the prevalence of asymptomatic SARS-CoV-2 antibodies in university athletic clubs where SARS-CoV-2 infections had repeatedly occurred, which will be helpful in discussing how to identify and prevent the transmission of infections within university athletic club communities.

Estimated Transmission Outcomes and Costs of SARS-CoV-2 Diagnostic Testing, Screening, and Surveillance Strategies Among a Simulated Population of Primary School Students

IMPORTANCE

In addition to illness, the COVID-19 pandemic has led to historic educational disruptions. In March 2021, the federal government allocated $10 billion for COVID-19 testing in US schools.

OBJECTIVE

Costs and benefits of COVID-19 testing strategies were evaluated in the context of full-time, in-person kindergarten through eighth grade (K-8) education at different community incidence levels.

DESIGN, SETTING, AND PARTICIPANTS

An updated version of a previously published agent-based network model was used to simulate transmission in elementary and middle school communities in the United States. Assuming dominance of the delta SARS-CoV-2 variant, the model simulated an elementary school (638 students in grades K-5, 60 staff) and middle school (460 students grades 6-8, 51 staff).

EXPOSURES

Multiple strategies for testing students and faculty/staff, including expanded diagnostic testing (test to stay) designed to avoid symptom-based isolation and contact quarantine, screening (routinely testing asymptomatic individuals to identify infections and contain transmission), and surveillance (testing a random sample of students to identify undetected transmission and trigger additional investigation or interventions).

MAIN OUTCOMES AND MEASURES

Projections included 30-day cumulative incidence of SARS-CoV-2 infection, proportion of cases detected, proportion of planned and unplanned days out of school, cost of testing programs, and childcare costs associated with different strategies. For screening policies, the cost per SARS-CoV-2 infection averted in students and staff was estimated, and for surveillance, the probability of correctly or falsely triggering an outbreak response was estimated at different incidence and attack rates.

RESULTS

Compared with quarantine policies, test-to-stay policies are associated with similar model-projected transmission, with a mean of less than 0.25 student days per month of quarantine or isolation. Weekly universal screening is associated with approximately 50% less in-school transmission at one-seventh to one-half the societal cost of hybrid or remote schooling. The cost per infection averted in students and staff by weekly screening is lowest for schools with less vaccination, fewer other mitigation measures, and higher levels of community transmission. In settings where local student incidence is unknown or rapidly changing, surveillance testing may detect moderate to large in-school outbreaks with fewer resources compared with schoolwide screening.

CONCLUSIONS AND RELEVANCE

In this modeling study of a simulated population of primary school students and simulated transmission of COVID-19, test-to-stay policies and/or screening tests facilitated consistent in-person school attendance with low transmission risk across a range of community incidence. Surveillance was a useful reduced-cost option for detecting outbreaks and identifying school environments that would benefit from increased mitigation.

Back to the Basics: A COVID-19 Surveillance Program Within a Local School District

BACKGROUND

A school district in Northern Ohio implemented a COVID-19 surveillance program from January 4 to May 21, 2021, as in-person school and extracurricular activities resumed.

METHODS

Among 560 staff members and >6300 students, random weekly testing was performed on 563 students and weekly for 204 students participating in extracurricular activities, and 553 staff.

RESULTS

Cases of COVID-19 were identified among 26 staff members and 23 students. Most of those infected were participating in extracurricular activities (14/23) and in the age range of 14-18. Percent positivity was low (range 0.2-2.4%) throughout the school surveillance program despite significant changes in positivity rate (2.8-19.8%).

CONCLUSION

This demonstrates that in a setting employing basic yet consistent mitigation strategies, there is low transmission among young children and adolescents as they return to in-person classes and activities. Maintaining layered prevention strategies implemented and sustained with fidelity can substantially limit transmission within schools.

COVID-19-Positive Testing in Minnesota High School Fall and Winter Sports: A Guide for Sports Risk

OBJECTIVE

To assess the effectiveness of coronavirus disease 2019 (COVID-19) prevention strategies used during sports participation.

DESIGN

To analyze prospective reports of student-athletes with COVID-19-positive tests to assess prevention strategies and risk factors by sports and seasons.

SETTING

Minnesota high schools.

PARTICIPANTS

Fall 2020 (August 24-October 30) and winter 2021 (January 2-March 12) student-athletes.

ASSESSMENT OF RISK FACTORS

Sports, indoor location, mask use, physical distancing, and season.

MAIN OUTCOME MEASURES

COVID-19-positive test rates.

METHODS

Self-selected schools voluntarily reported, in 2-week intervals, the number of student-athletes with COVID-19-positive tests in each sport and the number of athletes participating in each sport during the fall and winter sports seasons. The positive testing rates per 100 000 athletes were calculated for participants in each sport and compared by sports type and risk variables.

RESULTS

The high school age community-positive testing rate was 1298 per 100 000 students in the fall and 2396 in the winter. The student-athlete positive testing rate was 1500 per 100 000 athletes during the fall and 2800 during the winter (χ2 = 1.98, df = 1, P = 0.350). Positive tests per 100 000 athletes ranged from 197 (girls alpine skiing) to 4151 (wrestling). The incidence rates comparing indoor with outdoor sports (P = 0.001) and close-contact with physically distanced sports (P = 0.023) were significantly different, but the incidence rates comparing indoor masked with unmasked sports (P = ns) were not different.

CONCLUSION

Athletes competing in outdoor individual sports have less risk of a COVID-19-positive test compared with age-matched individuals in the community and indoor sports participants either wearing or not wearing masks during competition. Unmasked athletes in close proximity have the highest positive test rates, and unenforced masking is not associated with lower positive testing rates. More study is needed to understand mask effectiveness.

A Test-to-Stay Modified Quarantine Program for COVID-19 in Schools

BACKGROUND AND OBJECTIVES

Mandatory quarantine upon exposure to coronavirus disease 2019 (COVID-19) results in a substantial number of lost days of school. We hypothesized that implementation of a state-wide test-to-stay (TTS) program would allow more students to participate in in-person learning, and not cause additional clusters of COVID-19 cases due to in-school transmission.

METHODS

For the 2020-2021 academic year, Massachusetts implemented an opt-in TTS program, in which students exposed to COVID-19 in school are tested each school day with a rapid antigen test. If negative, students may participate in school-related activities that day. Testing occurs daily for a duration of 7 calendar days after exposure. Here, we report the results from the first 13 weeks of the program.

RESULTS

A total of 2298 schools signed up for TTS, and 504 167 individuals out of a total population of 860 457 consented. During the first 13 weeks with complete data, 1959 schools activated the program at least once for 102 373 individual, exposed students. Out of 328 271 tests performed, 2943 positive cases were identified (per person positivity rate, 2.9%, 95% confidence interval, 2.8-3.0). A minimum of 325 328 and a maximum of 497 150 days of in-person school were saved through participation in the program.

CONCLUSIONS

Daily, rapid on-site antigen testing is a safe and feasible alternative to mandatory quarantine and can be used to maximize safe in-person learning time during the pandemic.

Effectiveness of rapid antigen testing for screening of asymptomatic individuals to limit the transmission of SARS-CoV-2: A rapid review

Rapid antigen detection tests (RADTs) offer advantages over gold-standard reverse transcription polymerase chain reaction (RT-PCR) tests in that they are cheaper and provide faster results, thus enabling prompt isolation of positive SARS-CoV-2 cases and quarantine of close contacts. The aim of this study was to collate and synthesise empirical evidence on the effectiveness of rapid antigen testing for the screening (including serial testing) and surveillance of asymptomatic individuals to limit the transmission of SARS-CoV-2. A rapid review was undertaken in MEDLINE (EBSCO), EMBASE (OVID), Cochrane Library, Europe PMC and Google Scholar up until 19 July 2021, supplemented by a grey literature search. Of the identified 1222 records, 19 reports referring to 16 studies were included. Eight included studies examined the effectiveness of RADTs for population-level screening, four for pre-event screening and four for serial testing (schools, a prison, a university sports programme and in care homes). Overall, there is uncertainty regarding the effectiveness of rapid antigen testing for the screening of asymptomatic individuals to limit the transmission of SARS-CoV-2. This uncertainty is due to the inconsistent results, the relatively low number of studies identified, the predominantly observational and/or uncontrolled nature of the study designs used, and concerns regarding methodological quality. Given this uncertainty, more real-world research evidence in relevant settings, which is of good quality and timely, as well as economic evaluation, is required to inform public policy on the widespread use of RADTs in asymptomatic individuals.

Replacing quarantine of COVID-19 contacts with periodic testing is also effective in mitigating the risk of transmission

The quarantine of identified close contacts has been vital to reducing transmission rates and averting secondary infection risk before symptom onset and by asymptomatic cases. The effectiveness of this contact tracing strategy to mitigate transmission is sensitive to the adherence to quarantines, which may be lower for longer quarantine periods or in vaccinated populations (where perceptions of risk are reduced). This study develops a simulation model to evaluate contact tracing strategies based on the sequential testing of identified contacts after exposure as an alternative to quarantines, in which contacts are isolated only after confirmation by a positive test. The analysis considers different number and types of tests (PCR and lateral flow antigen tests (LFA)) to identify the cost-effective testing policies that minimize the expected infecting days post-exposure considering different levels of testing capacity. This analysis suggests that even a limited number of tests can be effective at reducing secondary infection risk: two LFA tests (with optimal timing) avert infectiousness at a level that is comparable to 14-day quarantine with 80–90% adherence, or equivalently, 7–9 day quarantine with full adherence (depending on the sensitivity of the LFA test). Adding a third test (PCR or LFA) reaches the efficiency of a 14-day quarantine with 90–100% adherence. These results are robust to the exposure dates of the contact, test sensitivity of LFA and alternative models of viral load evolution, which suggests that simple testing rules can be effective for improving contact tracing in settings where strict quarantine adherence is difficult to implement.

Return to School and COVID-19 Vaccination for Pediatric Solid Organ Transplant Recipients in the United States: Expert Opinion for 2021-2022

The COVID-19 pandemic continues to generate challenges for pediatric solid organ transplant (SOT) recipients and their families. As rates of COVID-19 fluctuate, new SARS-CoV-2 variants emerge, and adherence to and implementation of mitigation strategies vary from community to community, questions remain about the best and safest practices to prevent COVID-19 in vulnerable patients. Notably, decisions about returning to school remain difficult. We assembled a team of specialists in pediatric infectious diseases, transplant infectious diseases, public health, transplant psychology, and infection prevention and control to re-address concerns about school re-entry, as well as COVID-19 vaccines, for pediatric SOT recipients in the United States in 2021. Based on available literature and guidance from national organizations, we generated expert statements specific to pediatric SOT recipients focused on school attendance in 2021.

Secondary Transmission of COVID-19 in K-12 Schools: Findings From 2 States

OBJECTIVES

We evaluated the impact of distancing practices on secondary transmission of severe acute respiratory syndrome coronavirus 2 and the degree of sports-associated secondary transmission across a large diverse cohort of schools during spring 2021.

METHODS

Participating districts in North Carolina and Wisconsin and North Carolina charter schools offering in-person instruction between March 15, 2021 and June 25, 2021 reported on distancing policies, community- and school-acquired infections, quarantines, and infections associated with school-sponsored sports. We calculated the ratio of school-acquired to community-acquired infection, secondary attack rates, and the proportion of secondary transmission events associated with sports. To estimate the effect of distancing and bus practices on student secondary transmission, we used a quasi-Poisson regression model with the number of primary student cases as the denominator.

RESULTS

During the study period, 1 102 039 students and staff attended in-person instruction in 100 North Carolina school districts, 13 Wisconsin school districts, and 14 North Carolina charter schools. Students and staff had 7865 primary infections, 386 secondary infections, and 48 313 quarantines. For every 20 community-acquired infections, there was 1 within-school transmission event. Secondary transmissions associated with school sports composed 46% of secondary transmission events in middle and high schools. Relaxed distancing practices (<3 ft, 3 ft) and increased children per bus seat were not associated with increased relative risk of secondary transmission.

CONCLUSIONS

With universal masking, in-person education was associated with low rates of secondary transmission, even with less stringent distancing and bus practices. Given the rates of sports-associated secondary transmission, additional mitigation may be warranted.

Implementation of School-Based COVID-19 Testing Programs in Underserved Populations

Evidence suggests that coronavirus disease 2019 (COVID-19) testing in schools can add a layer of protection to reduce the spread of Severe Acute Respiratory Syndrome Coronavirus 2 and facilitate a safer return to in-person learning. Despite this evidence, implementation of testing in school settings has been challenging initially because of a lack of funding and limited availability of testing, but, as the pandemic has progressed and more funding and resources have been devoted to testing, other implementation challenges have arisen. We describe key implementation barriers and strategies that have been operationalized across 5 projects working to help schools with predominantly underserved populations who have faced significant COVID-19-related health disparities. We leveraged a key framework from the implementation science field to identify the challenges and used a matching tool to align implementation strategies to these challenges. Our findings suggest that the biggest obstacles to COVID-19 testing were the perceived relative advantages versus burden of COVID-19 testing, limited engagement with the target beneficiaries (eg, families, students, staff), and innovation complexity. Common strategies to overcome these challenges included identifying and preparing testing champions, altering incentive and allowance structures, assessing for readiness, and identifying barriers and facilitators. We aim to augment existing implementation guidance for schools by describing common barriers and recommended solutions from the implementation science field. Our results indicate a clear need to provide implementation support to schools to facilitate COVID-19 testing as an added layered mitigation strategy.

COVID-19 Outbreaks Associated With Youth Club Sports: Maricopa County, Arizona, September-November 2020

The Maricopa County Department of Public Health in Arizona investigated three COVID-19 outbreaks associated with club sports, two in tournaments and one in a hockey league. During September through November 2020, 195 team-associated and 69 secondary household contact cases were identified among 2093 athletes, coaches, and staff members; the team attack rate ranged from 6% to 72%. Outbreaks occurred during high community transmission periods in Maricopa County. Identification of contacts and characterization of prevention strategies were challenging because of limited cooperation from athletes, families, and staff. (Am J Public Health. 2022;112(2):216-219. https://doi.org/10.2105/AJPH.2021.306579).

Considerations for the Safe Operation of Schools During the Coronavirus Pandemic

During the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, providing safe in-person schooling has been a dynamic process balancing evolving community disease burden, scientific information, and local regulatory requirements with the mandate for education. Considerations include the health risks of SARS-CoV-2 infection and its post-acute sequelae, the impact of remote learning or periods of quarantine on education and well-being of children, and the contribution of schools to viral circulation in the community. The risk for infections that may occur within schools is related to the incidence of SARS-CoV-2 infections within the local community. Thus, persistent suppression of viral circulation in the community through effective public health measures including vaccination is critical to in-person schooling. Evidence suggests that the likelihood of transmission of SARS-CoV-2 within schools can be minimized if mitigation strategies are rationally combined. This article reviews evidence-based approaches and practices for the continual operation of in-person schooling.

Performance characteristics of the Abbott BinaxNOW SARS-CoV-2 antigen test in comparison to real-time RT-PCR and viral culture in community testing sites during November 2020

Point-of-care antigen tests are an important tool for SARS-CoV-2 detection. Antigen tests are less sensitive than real-time reverse-transcriptase PCR (rRT-PCR). Data on the performance of the BinaxNOW antigen test compared to rRT-PCR and viral culture by symptom and known exposure status, timing during disease or exposure period and demographic variables are limited. During November 3^rd-17^th, 2020, we collected paired upper respiratory swab specimens to test for SARS-CoV-2 by rRT-PCR and Abbott BinaxNOW (BinaxNOW) antigen test at two community testing sites in Pima County, Arizona. We administered a questionnaire to capture symptoms, known exposure status and previous SARS-CoV-2 test results. Specimens positive by either test were analyzed by viral culture. Previously we showed overall BinaxNOW sensitivity was 52.5%. Here we showed BinaxNOW sensitivity increased to 65.7% among currently symptomatic individuals reporting a known exposure. BinaxNOW sensitivity was lower among participants with a known exposure and previously symptomatic (32.4%) or never symptomatic (47.1%) within 14 days of testing. Sensitivity was 71.1% in participants within a week of symptom onset. In participants with a known exposure, sensitivity was highest 8-10 days post-exposure (75%). The positive predictive value for recovery of virus in cell culture was 56.7% for BinaxNOW-positive and 35.4% for rRT-PCR-positive specimens. Result reporting time was 2.5 hours for BinaxNOW and 26 hours for rRT-PCR. Point-of-care antigen tests have a shorter turn-around time compared to laboratory-based nucleic acid amplification tests, which allows for more rapid identification of infected individuals. Antigen test sensitivity limitations are important to consider when developing a testing program.

SARS-CoV-2 testing strategies to contain school-associated transmission: model-based analysis of impact and cost of diagnostic testing, screening, and surveillance

Background

In March 2021, the Biden administration allocated $10 billion for COVID-19 testing in schools. We evaluate the costs and benefits of testing strategies to reduce the infection risks of full-time in-person K-8 education at different levels of community incidence.

Methods

We used an agent-based network model to simulate transmission in elementary and middle school communities, parameterized to a US school structure and assuming dominance of the delta COVID-19 variant. We assess the value of different strategies for testing students and faculty/staff, including expanded diagnostic testing ("test to stay" policies that take the place of isolation for symptomatic students or quarantine for exposed classrooms); screening (routinely testing asymptomatic individuals to identify infections and contain transmission); and surveillance (testing a random sample of students to signaling undetected transmission and trigger additional investigation or interventions).

Main outcome measures

We project 30-day cumulative incidence of SARS-CoV-2 infection; proportion of cases detected; proportion of planned and unplanned days out of school; and the cost of testing programs and of childcare costs associated with different strategies. For screening policies, we further estimate cost per SARS-CoV-2 infection averted in students and staff, and for surveillance, probability of correctly or falsely triggering an outbreak response at different incidence and attack rates.

Results

Accounting for programmatic and childcare costs, "test to stay" policies achieve similar model-projected transmission to quarantine policies, with reduced overall costs. Weekly universal screening prevents approximately 50% of in-school transmission, with a lower projected societal cost than hybrid or remote schooling. The cost per infection averted in students and staff by weekly screening is lower for older students and schools with higher mitigation and declines as community transmission rises. In settings where local student incidence is unknown or rapidly changing, surveillance may trigger detection of moderate-to-large in-school outbreaks with fewer resources compared to screening.

Conclusions

"Test to stay" policies and/or screening tests can facilitate consistent in-person school attendance with low transmission risk across a range of community incidence. Surveillance may be a useful reduced-cost option for detecting outbreaks and identifying school environments that may benefit from increased mitigation.

Guidance for Implementing COVID-19 Prevention Strategies in the Context of Varying Community Transmission Levels and Vaccination Coverage

COVID-19 vaccination remains the most effective means to achieve control of the pandemic. In the United States, COVID-19 cases and deaths have markedly declined since their peak in early January 2021, due in part to increased vaccination coverage (1). However, during June 19-July 23, 2021, COVID-19 cases increased approximately 300% nationally, followed by increases in hospitalizations and deaths, driven by the highly transmissible B.1.617.2 (Delta) variant* of SARS-CoV-2, the virus that causes COVID-19. Available data indicate that the vaccines authorized in the United States (Pfizer-BioNTech, Moderna, and Janssen [Johnson & Johnson]) offer high levels of protection against severe illness and death from infection with the Delta variant and other currently circulating variants of the virus (2). Despite widespread availability, vaccine uptake has slowed nationally with wide variation in coverage by state (range = 33.9%-67.2%) and by county (range = 8.8%-89.0%).^† Unvaccinated persons, as well as persons with certain immunocompromising conditions (3), remain at substantial risk for infection, severe illness, and death, especially in areas where the level of SARS-CoV-2 community transmission is high. The Delta variant is more than two times as transmissible as the original strains circulating at the start of the pandemic and is causing large, rapid increases in infections, which could compromise the capacity of some local and regional health care systems to provide medical care for the communities they serve. Until vaccination coverage is high and community transmission is low, public health practitioners, as well as schools, businesses, and institutions (organizations) need to regularly assess the need for prevention strategies to avoid stressing health care capacity and imperiling adequate care for both COVID-19 and other non-COVID-19 conditions. CDC recommends five critical factors be considered to inform local decision-making: 1) level of SARS-CoV-2 community transmission; 2) health system capacity; 3) COVID-19 vaccination coverage; 4) capacity for early detection of increases in COVID-19 cases; and 5) populations at increased risk for severe outcomes from COVID-19. Among strategies to prevent COVID-19, CDC recommends all unvaccinated persons wear masks in public indoor settings. Based on emerging evidence on the Delta variant (2), CDC also recommends that fully vaccinated persons wear masks in public indoor settings in areas of substantial or high transmission. Fully vaccinated persons might consider wearing a mask in public indoor settings, regardless of transmission level, if they or someone in their household is immunocompromised or is at increased risk for severe disease, or if someone in their household is unvaccinated (including children aged <12 years who are currently ineligible for vaccination).