ABSTRACT
SARS-CoV-2 infections in childcare and school settings potentially bear occupational risks to educational staff. We analyzed data derived from voluntary, PCR-based screening of childcare educators and teachers attending five testing sites in Berlin, Germany, between June and December 2020. Within seven months, 17,491 tests were performed (4,458 educators, 13,033 teachers). Participants were largely female (72.9%), and median age was 41 years. Overall, SARS-CoV-2 infection prevalence was 1.2% (95%CI, 1.1-1.4%). Prevalence in educational staff largely resembled community incidence until the start of the second pandemic wave in mid-September 2020, when an unsteady prevalence plateau was reached. Then, infection prevalence in teachers (1.2% [95%CI, 0.8-1.8%]) did not significantly differ from the population prevalence (0.9% [0.6-1.4%]) but it was increased in educators (2.6% [1.6-4.0%]; aOR, 1.6 [1.3-2.0]). Irrespective of occupation, those that reported contact to a confirmed SARS-CoV-2 case outside of work had increased risk of infection (aOR, 3.0 [95%CI, 1.5-5.5]). In a step-wise backwards selection, the best set of associated factors with SARS-CoV-2 infection involved age, occupation, and calendar week. These results are in line with findings that teachers do not bear an increased risk of SARS-CoV-2 infection, while childcare educators do. Infection control and prevention measures need to be strengthened in child care settings to further reduce respective occupational hazards. At the same time, the private environment appears to be the main source of SARS-CoV-2 infection for educational staff.
ABSTRACT
Summary/AbstractO_ST_ABSIntroductionC_ST_ABSContainment of the COVID-19 pandemic requires broad-scale testing. Laboratory capacities for real-time-PCR were increased, and are complemented by Ag-tests. However, sample-collection still requires qualified personnel and protective equipement, may produce transmission to others during conduct and travel, and is perceived uncomfortable. We tested sensitivity of three simplified self-sampling techniques compared to professional-collected combined oro-nasopharyngeal samples (cOP/NP). MethodsFrom 62 symptomatic COVID-19 outpatients, we obtained simultaneously three self- and one professional-collected sample after initial confirmation in a testing centre: (i) combination swab (tongue, cheek, both nasal vestibula, MS, (ii) saliva sponge combined with both nasal vestibula, SN, and (iii) gargled tap water, GW, (iv) professionally-collected cOP/NP (standard). We compared the results of SARS-CoV-2 PCR-assays detecting E-gene and ORF1ab for the different sample types and performed bivariate statistical analysis to determine the variables reducing sensitivity of the self-collecting procedures. ResultsSARS-CoV-2 RNA was detected in all 62 professionally-collected cOP/NP. MS and SN samples showed a sensitivity of 95.2% (95%CI 86.5-99.0) and GW samples of 88.7% (78.1-95.3). Compared to the median ct-values of cOP/NP samples for E-gene (20.7) and ORF1ab (20.2) these were higher for MS (22.6 and 21.8), SN (23.3 and 22.3), and for GW (30.3 and 29.8). For MS and SN samples but not for GW specimens, false negativity in bivariate analysis was associated with non-German mother-tongue, number of sampling errors, and with symptom duration. For symptom duration of [≤]8 days, test sensitivity for SN samples was 98.2% (95%CI 90.4-100.0) and for MS 96.4% (95%CI 87.7-99.6) and drops after day 8 below 90%. DiscussionThe study is limited to sensitivity of self-collection in symptomatic patients. Still, in this group, self-collected oral/nasal/saliva samples are reliable alternatives to professional-collected cOP/NP samples, if symptom duration does not exceed eight days and operational errors are minimized. Self-sampling could contribute to up-scaling of safe and efficient testing.
ABSTRACT
Within five weeks in early 2021, B.1.1.7 became the dominant SARS-CoV-2 lineage at an outpatient testing site in Berlin. Characteristics including Ct-values of 193 and 125 recently ill outpatients with B.1.1.7 and wildtype virus, respectively, were similar, except for more commonly reported sore throat and travel, and less frequently stated loss of smell and taste in the former.
ABSTRACT
BackgroundSchool attendance during the SARS-CoV-2 pandemic is intensely debated. Modelling studies suggest that school closures contribute to community transmission reduction. However, data among school-attending students and staff are scarce. In November 2020, we examined SARS-CoV-2 infections and seroreactivity in 24 randomly selected school classes and connected households in Berlin, Germany. MethodsStudents and school staff were examined, oro-nasopharyngeal swabs and blood samples collected, and SARS-CoV-2 infection and IgG antibodies detected by RT-PCR and ELISA. Household members performed self-swabs. Individual and institutional infection prevention and control measures were assessed. Classes with SARS-CoV-2 infection and connected household members were re-tested after one week. Findings1119 participants were examined, including 177 primary and 175 secondary school students, 142 staff, and 625 household members. Participants reported mainly cold symptoms (19{middle dot}4%). SARS-CoV-2 infection occurred in eight of 24 classes affecting each 1-2 individuals. Infection prevalence was 2{middle dot}7% (95%CI; 1{middle dot}2-5{middle dot}0%; 9/338), 1{middle dot}4% (0{middle dot}2-5{middle dot}1%; 2/140), and 2{middle dot}3% (1{middle dot}3-3{middle dot}8%; 14/611) among students, staff and household members, respectively, including quarantined persons. Six of nine infected students were asymptomatic. Prevalence increased with inconsistent facemask use in school, way to school on foot, and case-contacts outside school. IgG antibodies were detected in 2{middle dot}0% (0{middle dot}8-4{middle dot}1%; 7/347), 1{middle dot}4% (0{middle dot}2-5{middle dot}0%; 2/141) and 1{middle dot}4% (0{middle dot}6-2{middle dot}7%; 8/576), respectively. For three of nine households with infection(s) detected at cross-sectional assessment, origin in school seemed possible. After one week, no school-related, secondary infections appeared in affected classes; the attack rate in connected households was 1{middle dot}1%. InterpretationThese data suggest that school attendance under preventive measures is feasible, provided their rigorous implementation. In balancing threats and benefits of open versus closed schools during the pandemic, parents and society need to consider possible spill-overs into their households. Deeper insight is needed into the infection risks due to being a schoolchild as compared to attending school. FundingSenate of Berlin.
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BackgroundBriefly before the first peak of the COVID-19 pandemic in Berlin, Germany, schools closed in mid-March 2020 for six weeks. Following re-opening, schools gradually resumed operation at a reduced level for nine weeks preceding the summer holidays. AimDuring this phase, we conducted a situational assessment in schools among students and teachers as to infection status, symptoms, affective, behavioural, educational issues, and preventive measures. MethodsAt twenty-four randomly selected primary and secondary schools, one class each was examined. Oro-nasopharyngeal swabs and capillary blood samples were collected to assess SARS-CoV-2 infection (PCR) and specific IgG (ELISA), respectively. Medical history, household and schooling characteristics, leisure time activities, fear of infection, risk perception, hand hygiene, physical distancing, and facemask wearing were assessed. ResultsAmong 535 participants (385 students, 150 staff), one teenager was SARS-CoV-2 infected (0.2%), and seven individuals exhibited specific IgG (1.3%); 16% reported symptoms upon examination, and 48% in the preceding 14 days. Compared to before the pandemic, the proportion of leisure time spent as screen-time increased, and the majority of primary school students reported reduced physical activity. Fear of infection and risk perception were relatively low, but acceptance of adapted health behaviours was high. Governmental preventive measures were adequately implemented, with primary schools performing better than secondary schools. ConclusionIn this phase of rare infection and low seroreactivity, individual and school-level infection prevention and control measures were largely adhered to. Nevertheless, vigilance, continued and proactive preventive measures, and well-rehearsed reaction options are essential to cope with increasing pandemic activity.
ABSTRACT
ObjectivesThe comparatively large proportion of asymptomatic SARS-CoV-2 infections in the youngest children opens up the possibility that kindergartens represent reservoirs of infection. However, actual surveys in kindergartens beyond individual outbreaks are rare. At the beginning of the second pandemic wave in Berlin, Germany, i.e., end of September 2020, we screened SARS-CoV-2 infections among kindergarten children, staff and connected household members. MethodsTwelve kindergartens were randomly selected in the Berlin metropolitan area, and a total of 720 participants were recruited (155 pre-school children, 78 staff, 487 household members). Participants were briefly examined and interviewed, and SARS-CoV-2 infections and anti-SARS-Cov-2 IgG antibodies were assessed. ResultsSigns and symptoms, largely resembling common cold, were present in 24.2% of children and 28.9% of staff. However, no SARS-CoV-2 infection was detected among 701 PCR-tested individuals, and only one childcare worker showed IgG seroreactivity (0.15%; 1/672). ConclusionsAgainst a backdrop of increased pandemic activity in the community, this cross-sectional study does not suggest that kindergartens are silent transmission reservoirs. Nevertheless, at increasing pandemic activity, reinforced precautionary measures and repeated routine testing appears advisable.
