Objectives: This longitudinal cohort study aims to assess the extent and patterns of seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in school-attending children, and their parents and school personnel. It will examine risk factors for infection, the relationship between seropositivity and symptoms, and temporal persistence of antibodies. Methods: The study (Ciao Corona) will enroll a regionally representative, random sample of schools in the canton of Zurich, where 18% of the Swiss population live. Children aged 5–16 years, attending primary and secondary schools, and their parents and school personnel are invited. Venous blood and saliva samples are collected for serological testing in June/July 2020, in October/November 2020, and in March/April 2021. Bi-monthly questionnaires will cover SARS-CoV-2 symptoms and tests, health, preventive behavior, and lifestyle information. Hierarchical Bayesian logistic regression models will account for sensitivity and specificity of the serological tests in the analyses and complex sampling structure, i.e., clustering within classes and schools. Results and conclusions: This unique school-based study will allow describing temporal trends of immunity, evaluate effects of preventive measures and will inform goal-oriented policy decisions during subsequent outbreaks. Trial registration ClinicalTrials.gov Identifier: NCT04448717, registered June 26, 2020. https://clinicaltrials.gov/ct2/show/NCT04448717.

Variation in utilization of healthcare services is influenced by patient, provider and healthcare system characteristics. It could also be related to the evidence supporting their use, as reflected in the availability and strength of recommendations in clinical guidelines. In this study, we analyzed the geographic variation of colorectal, breast and prostate cancer screening utilization in Switzerland and the influence of available guidelines and different modifiers of access. Colonoscopy, mammography and prostate specific antigen (PSA) testing use in eligible population in 2014 was assessed with administrative claims data. We ran a multilevel multivariable logistic regression model and calculated Moran’s I and regional level median odds ratio (MOR) statistics to explore residual geographic variation. In total, an estimated 8.1% of eligible persons received colonoscopy, 22.3% mammography and 31.3% PSA testing. Low deductibles, supplementary health insurance and enrollment in a managed care plan were associated with higher screening utilization. Cantonal breast cancer screening programs were also associated with higher utilization. Spatial clustering was observed in the raw regional utilization of all services, but only for prostate cancer screening in regional residuals of the multilevel model. MOR was highest for prostate cancer screening (1.24) and lowest for colorectal cancer screening (1.16). The reasons for the variation of the prostate cancer screening utilization, not recommended routinely without explicit shared decision-making, could be further investigated by adding provider characteristics and patient preference information. This first cross-comparison of different cancer screening patterns indicates that the strength of recommendations, mediated by specific health policies facilitating screening, may indeed contribute to variation.

Objectives: To determine the variation in SARS-CoV-2 seroprevalence in school children and the relationship with self-reported symptoms. Design: Baseline measurements of a longitudinal cohort study ( Ciao Corona ) from June to July 2020. Setting: 55 schools stratified by district in the canton of Zurich, Switzerland. Participants: 2585 children (1339 girls; median age: 11 years, age range: 6–16 years), attending grades 1–2, 4–5 and 7–8. Main outcome measures: Variation in seroprevalence of SARS-CoV-2 in children across 12 cantonal districts, schools and grades, assessed using Luminex-based test of four epitopes for IgG, IgA and IgM (Antibody Coronavirus Assay,ABCORA 2.0). Clustering of cases within classes. Association of seropositivity and symptoms. Comparison with seroprevalence in adult population, assessed using Luminex-based test of IgG and IgA (Sensitive Anti-SARS-CoV-2 Spike Trimer Immunoglobulin Serological test). Results: Overall seroprevalence was 2.8% (95% CI 1.5% to 4.1%), ranging from 1.0% to 4.5% across districts. Seroprevalence in grades 1–2 was 3.8% (95% CI 2.0% to 6.1%), in grades 4–5 was 2.4% (95% CI 1.1% to 4.2%) and in grades 7–8 was 1.5% (95% CI 0.5% to 3.0%). At least one seropositive child was present in 36 of 55 (65%) schools and in 44 (34%) of 131 classes where ≥5 children and ≥50% of children within the class were tested. 73% of children reported COVID-19-compatible symptoms since January 2020, with the same frequency in seropositive and seronegative children for all symptoms. Seroprevalence of children and adults was similar (3.2%, 95% credible interval (CrI) 1.7% to 5.0% vs 3.6%, 95% CrI 1.7% to 5.4%). The ratio of confirmed SARS-CoV-2 cumulative incidence-to-seropositive cases was 1:89 in children and 1:12 in adults. Conclusions: SARS-CoV-2 seroprevalence was low in children and similar to that in adults by the end of June 2020. Very low ratio of diagnosed-to-seropositive children was observed. We did not detect clustering of SARS-CoV-2-seropositive children within classes, but the follow-up of this study will shed more light on transmission within schools. Trial registration number: NCT04448717 .

Background: Nursing home residents face many barriers to accessing specialist physician outpatient care. However, little data exists on how specialty care use changes when individuals transition to a nursing home in the US. Methods: We studied specialist outpatient visits for new long‐term care (LTC) residents within 1 year before and after their transition to nursing home residence using the Minimum Data Set v3.0 (MDS) and a 20% sample of Medicare fee‐for‐service claims in 2014–2018. To focus on residents requiring specialty care at baseline, we limited the cohort to residents with specialty care in the 13–24 months before LTC transition. We then measured the proportion of residents receiving at least one visit in the 12 months before the transition and the 12 months after the transition. We also examined subgroups of residents with a prior diagnosis likely requiring long‐term specialty care (e.g., multiple sclerosis). Finally, we examined whether there was continuity of care within the same specialty care provider. Results: Among 39,288 new LTC transitions identified in 2016–2017, 17,877 (45.5%) residents had a prior specialist visit 13–24 months before the transition. Among them, the proportion of residents with specialty visits decreased consistently in all specialties in the 12 months after the transition, ranging from a relative decrease of 14.4% for orthopedics to 67.9% for psychiatry. The relative decrease among patients with a diagnosis likely requiring specialty care ranged from 0.9% for neurology in patients with multiple sclerosis to 67.1% for psychiatry in patients with severe mental illness. Among residents who continued visiting a specialist, 78.9% saw the same provider as before the transition. Conclusions: The use of specialty care falls significantly after patients transition to a nursing home. Further research is needed to understand what drives this drop in use and whether interventions, such as telemedicine can ameliorate potential barriers to specialty care.

Importance: Understanding transmission and impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in school children is critical to implement appropriate mitigation measures. Objective: To determine the variation in SARS-CoV-2 seroprevalence in school children across districts, schools, grades, and classes, and the relationship of SARS-CoV-2 seroprevalence with self-reported symptoms. Design: Cross-sectional analysis of baseline measurements of a longitudinal cohort study (Ciao Corona) from June-July 2020. Setting: 55 randomly selected schools and classes stratified by district in the canton of Zurich, Switzerland (1.5 million inhabitants). Participants: Children, aged 6-16 years old, attending grades 1-2, 4-5 and 7-8. Exposure: Exposure to circulating SARS-CoV-2 between February and June 2020 including public lock-down and school closure (March 16-May 10, 2020). Main Outcomes and Measures: Variation in seroprevalence of SARS-CoV-2 in children across 12 cantonal districts, schools, and grades using a Luminex-based antibody test with four targets for each of IgG, IgA and IgM. Clustering of cases within classes. Analysis of associations of seropositivity and symptoms. Comparison of seroprevalence with a randomly selected adult population, based on Luminex-based IgG and IgA antibody test of Corona Immunitas. Results: In total, 55 schools and 2585 children were recruited (1337 girls, median age 11, age range 6-16 years). Overall seroprevalence was 2.8 % (95% CI 1.6–4.1%), ranging from 1.0% to 4.5% across districts. Seroprevalence was 3.8% (1.9-6.1%) in grades 1-2, 2.5% (1.1-4.2%) in grades 4-5, and 1.5% (0.5-3.0%) in grades 7–8. At least one case was present in 36/55 tested schools and in 43/128 classes with ≥50% participation rate and ≥5 children tested. 73% of children reported COVID-19 compatible symptoms since January 2020, but none were reported more frequently in seropositive compared to seronegative children. Seroprevalence of children was very similar to seroprevalence of randomly selected adults in the same region in June-July 2020, measured with the same Corona Immunitas test, combining IgG and IgA (3.1%, 95% CI 1.4-5.4%, versus 3.3%, 95% CI 1.4-5.5%). Conclusions and Relevance: Seroprevalence was inversely related to age and revealed a dark figure of around 90 when compared to 0.03% confirmed PCR+ cases in children in the same area by end of June. We did not find clustering of SARS-CoV-2 seropositive cases in schools so far, but the follow-up of this school-based study will shed more light on transmission within and outside schools. Trial registration: http://ClinicalTrials.gov Identifier: NCT04448717 , registered June 26, 2020. https://clinicaltrials.gov/ct2/show/NCT04448717 Key Points: Question: What is the variation in seroprevalence of SARS-CoV-2 cases in school children across districts, schools and classes? Findings: Among 55 randomly selected schools and 2585 children, 2.8 % (95% CI 1.6-4.1%) of children had SARS-CoV-2 antibodies, similar to the seroprevalence in the adult population in the same region but showing a much higher dark figure (89 versus 12 in adults). A third of tested classes had at least one SARS-CoV-2 case, and higher seroprevalence was observed in lower grades. Seropositive children did not report SARS-CoV-2 infection symptoms more often than seronegative children. Meaning: The results so far do not suggest substantial transmission within schools. In contrast to the current literature, younger children seem to be infected slightly more often; the striking dark figure of 89 could be partly due to the fact that symptoms compatible with COVID - 19 were highly prevalent in children and do not help to differentiate between seropositive and seronegative children.