Prevalence of SARS-CoV-2 Infections Among Students, Teachers, and Household Members During Lockdown and Split Classes in Berlin, Germany

SARS-CoV-2 testing strategies for a safe (post-)pandemic implementation of school music trips and their impact on participants' health

Introduction

During the coronavirus disease-19 (COVID-19) lockdowns, children repeatedly experienced social isolation. Dealing with the resulting post-pandemic health implications remains a challenge. The role of group recreational activities is crucial in promoting children's health; however the implementation can encounter challenges, especially when infections such as COVID-19 are surging.

Objectives

In this prospective observational study, we aimed to investigate whether safe cohorts can be created through appropriate test strategies to facilitate music trips during the COVID-19 waves. The primary outcome was the occurrence of positive cases during the journey. Secondarily, a survey was conducted to evaluate the physical and mental health status of participants before and after the first journey.

Methods

Two school music trips were conducted. The first trip (T1) took place from 4 January 2022 to 9 January 2022, and the second trip (T2) from 3 January 2023 to 8 January 2023. For T1, central laboratory SARS-CoV-2 polymerase chain reaction (PCR) pool tests were performed before departure. For T2, prior point-of-care (PoC) PCR pool tests were conducted to validate the findings. A hygiene protocol was mandatory for T1 and recommended for T2.

Results

Before T1, 95 volunteers underwent PCR laboratory pool testing, which revealed one positive COVID-19 case. During the travel, one student had a positive antigen test. Questionnaires for the mental health status were collected before T1 from 95 participants and again as a follow-up after T1 from 79 participants. There was a significant decrease in cold symptoms among students (p = 0.002). Following this, the perceived risk of infection significantly increased in the students' group (p = 0.019). Additionally, anxiety symptoms [as measured using generalized anxiety disorder (GAD)-7 score] and the fear of getting infected marginally increased in students. All T1 participants indicated that they would be willing to attend a similar trip again. In the initial T2 pool testing, 88 participants took part. Two participants tested positive for SARS-CoV-2, with one solely showing signs of a subsiding infection and the other being highly infectious, which led to the exclusion of the highly infectious participant from the travel. During the trip and the follow-up period, no further cases were reported.

Conclusion

Both testing concepts effectively identified positive "SARS-CoV-2 cases in advance and prevented transmissions, enabling safe school music trips during the winter. The use of PoC-PCR may be superior in terms of time efficiency and flexibility. Despite the increase in the perceived fear of infection among children, the overall experience of the journey was positive.

Health-related quality of life and impact of socioeconomic status among primary and secondary school students after the third COVID-19 wave in Berlin, Germany

In the earlier phases of the COVID-19 pandemic, studies in Germany and elsewhere found an overall reduction in health-related quality of life (HRQoL) among students. However, there is little evidence on later pandemic stages as well as socioeconomic influencing factors. We aimed to (1) describe HRQoL in a Berlin student cohort at two time points in mid-2021, and to (2) analyze the effects of household income and education. We assessed HRQoL of students from 24 randomly selected primary and secondary schools in Berlin, Germany, with the KIDSCREEN-10 index in June and September 2021. To adjust for non-response bias, inverse probability weighting was applied. The potential effects of both household income and education (lower vs. higher) were estimated in generalized linear mixed models, based on prior assumptions presented in directed acyclic graphs. Our cohort comprised 660 students aged 7-19 years. In June 2021, 11.3% [95% CI = 9.0% - 14.0%] reported low HRQoL, whereas in September 2021, this increased to 13.7% [95% CI = 11.1% - 16.5%], with adolescent girls more frequently reporting low HRQoL at both time points (20% [95% CI = 17.1% - 23.3%] and 29% [95% CI = 25.5% - 32.5%]) compared to boys and younger children. While there was no statistically significant total effect of lower household income on HRQoL, a negative effect of lower household education was statistically significant (β = -2.15, SE 0.95, 95% CI = -4.01 to -0.29, p = 0.024). In summary, students' HRQoL in mid-2021 was better than that documented in other studies conducted at pandemic onset using KIDSCREEN-10. Female adolescents reported low HRQoL more often, and lower household education significantly reduced children's HRQoL. Support strategies for psychosocial wellbeing should consider socioeconomically disadvantaged children as important target groups.

Generalized anxiety disorder in Berlin school children after the third COVID-19 wave in Germany: a cohort study between June and September 2021

BACKGROUND

During the COVID-19 pandemic, children and adolescents worldwide have disproportionally been affected in their psychological health and wellbeing. We conducted a cohort study among German school children, aiming at assessing levels of general anxiety disorder (GAD) and identifying associated factors in the second pandemic year.

METHODS

A cohort of 660 students from 24 Berlin schools was recruited to fill in questionnaires including the GAD-7 tool on anxiety symptoms at three time points between June and September 2021. To adjust for non-random attrition, we applied inverse probability weighting. We describe reported GAD levels stratified by time point, sex, and school type and report odds ratios from univariate logistic regression.

RESULTS

In total, 551 participants (83%) filled in at least one questionnaire at any time point. At the first time point in June 2021, 25% of the children and adolescents reported anxiety symptoms with a GAD-7 score ≥ 5, decreasing to 16% in August 2021 directly after the summer holidays and rising again to 26% in September 2021. The majority of reported anxiety levels belonged to the least severe category. Being female, attending secondary school, coming from a household with lower education or with lower income level, and being vaccinated against COVID-19 were significantly linked with reporting anxiety symptoms. Preceding COVID-19 infection and anxiety were negatively associated.

CONCLUSION

Overall, anxiety in school children was lower in mid-2021 than in the first pandemic year, but still double compared to pre-pandemic data. Reporting of anxiety symptoms during the second pandemic year was especially high in females and in secondary school students. Policy makers should pay additional attention to the mental health status of school children, even as the pandemic situation might stabilize.

Infection and transmission risks of COVID-19 in schools and their contribution to population infections in Germany: A retrospective observational study using nationwide and regional health and education agency notification data

BACKGROUND

School-level infection control measures in Germany during the early Coronavirus Disease 2019 (COVID-19) pandemic differed across the 16 federal states and lacked a dependable evidence base, with available evidence limited to regional data restricted to short phases of the pandemic. This study aimed to assess the (a) infection risks in students and staff; (b) transmission risks and routes in schools; (c) effects of school-level infection control measures on school and population infection dynamics; and (d) contribution of contacts in schools to population cases.

METHODS AND FINDINGS

For this retrospective observational study, we used German federal state (NUTS-2) and county (NUTS-3) data from public health and education agencies from March 2020 to April 2022. We assessed (a) infection risk as cumulative risk and crude risk ratios and (b) secondary attack rates (SARs) with 95% confidence interval (CI). We used (c) multiple regression analysis for the effects of infection control measures such as reduced attendance, mask mandates, and vaccination coverage as absolute reduction in case incidence per 100,000 inhabitants per 14 days and in percentage relative to the population, and (d) infection dynamic modelling to determine the percentage contribution of school contacts to population cases. We included (a) nationwide NUTS-2 data from calendar weeks (W) 46-50/2020 and W08/2021-W15/2022 with 3,521,964 cases in students and 329,283 in teachers; (b) NUTS-3 data from W09-25/2021 with 85,788 student and 9,427 teacher cases; and (c) detailed data from 5 NUTS-3 regions from W09/2020 to W27/2021 with 12,814 cases (39% male, 37% female; median age 14, range 5 to 63), 43,238 contacts and 4,165 secondary cases for students (for teachers, 14,801 [22% male, 50% female; median age 39, range 16 to 75], 5,893 and 472). Infection risk (a) for students and teachers was higher than the population risk in all phases of normal presence class and highest in the early 2022 omicron wave with 30.6% (95% CI 30.5% to 32.6%) of students and 32.7% (95% CI 32.6% to 32.8%) of teachers infected in Germany. SARs (b) for students and staff were below 5% in schools throughout the study period, while SARs in households more than doubled from 13.8% (95% CI 10.6% to 17.6%) W21-39/2020 to 28.7% (95% CI 27% to 30.4%) in W08-23/2021 for students and 10.9% (95% CI 7% to 16.5%) to 32.7% (95% CI 28.2% to 37.6%) for staff. Most contacts were reported for schools, yet most secondary cases originated in households. In schools, staff predominantly infected staff. Mandatory surgical mask wearing during class in all schools was associated with a reduction in the case incidence of students and teachers (c), by 56/100,000 persons per 14 days (students: 95% CI 47.7 to 63.4; teachers: 95% CI 39.6 to 71.6; p < 0.001) and by 29.8% (95% CI 25% to 35%, p < 0.001) and 24.3% (95% CI 13% to 36%, p < 0.001) relative to the population, respectively, as were reduced attendance and higher vaccination coverage. The contribution of contacts in schools to population cases (d) was 2% to 20%, lowest during school closures/vacation and peaked during normal presence class intervals, with the overall peak early during the omicron wave. Limitations include underdetection, misclassification of contacts, interviewer/interviewee dependence of contact-tracing, and lack of individual-level confounding factors in aggregate data regression analysis.

CONCLUSION

In this study, we observed that open schools under hygiene measures and testing strategies contributed up to 20% of population infections during the omicron wave early 2022, and as little as 2% during vacations/school closures; about a third of students and teachers were infected during the omicron wave in early 2022 in Germany. Mandatory mask wearing during class in all school types and reduced attendance models were associated with a reduced infection risk in schools.

Psychosocial Wellbeing of Schoolchildren during the COVID-19 Pandemic in Berlin, Germany, June 2020 to March 2021

The COVID-19 pandemic and related restrictions have affected the wellbeing of schoolchildren worldwide, but the extent and duration of specific problems are still not completely understood. We aimed to describe students’ psychosocial and behavioral parameters and associated factors during the COVID-19 pandemic in Berlin, Germany. Our longitudinal study included 384 students from 24 randomly selected Berlin primary and secondary schools, assessing psychosocial wellbeing at four time points between June 2020 and March 2021. We analyzed temporal changes in the proportions of anxiety, fear of infection, reduced health-related quality of life (HRQoL), physical activity and social contacts, as well as sociodemographic and economic factors associated with anxiety, fear of infection and HRQoL. During the observation period, the presence of anxiety symptoms increased from 26.2% (96/367) to 34.6% (62/179), and fear of infection from 28.6% (108/377) to 40.6% (73/180). The proportion of children with limited social contacts (<1/week) increased from 16.4% (61/373) to 23.5% (42/179). Low physical activity (<3 times sports/week) was consistent over time. Low HRQoL was observed among 44% (77/174) of children. Factors associated with anxiety were female sex, increasing age, secondary school attendance, lower household income, and the presence of adults with anxiety symptoms in the student´s household. Fear of infection and low HRQoL were associated with anxiety. A substantial proportion of schoolchildren experienced unfavorable psychosocial conditions during the COVID-19 pandemic in 2020/2021. Students from households with limited social and financial resilience require special attention.

Effective high-throughput RT-qPCR screening for SARS-CoV-2 infections in children

Systematic SARS-CoV-2 testing is a valuable tool for infection control and surveillance. However, broad application of high sensitive RT-qPCR testing in children is often hampered due to unpleasant sample collection, limited RT-qPCR capacities and high costs. Here, we developed a high-throughput approach ('Lolli-Method') for SARS-CoV-2 detection in children, combining non-invasive sample collection with an RT-qPCR-pool testing strategy. SARS-CoV-2 infections were diagnosed with sensitivities of 100% and 93.9% when viral loads were >106 copies/ml and >103 copies/ml in corresponding Naso-/Oropharyngeal-swabs, respectively. For effective application of the Lolli-Method in schools and daycare facilities, SEIR-modeling indicated a preferred frequency of two tests per week. The developed test strategy was implemented in 3,700 schools and 698 daycare facilities in Germany, screening over 800,000 individuals twice per week. In a period of 3 months, 6,364 pool-RT-qPCRs tested positive (0.64%), ranging from 0.05% to 2.61% per week. Notably, infections correlated with local SARS-CoV-2 incidences and with a school social deprivation index. Moreover, in comparison with the alpha variant, statistical modeling revealed a 36.8% increase for multiple (≥2 children) infections per class following infections with the delta variant. We conclude that the Lolli-Method is a powerful tool for SARS-CoV-2 surveillance and can support infection control in schools and daycare facilities.