Longitudinal humoral and cell-mediated immune responses in a population-based cohort in Zurich, Switzerland between March and June 2022 - evidence for protection against Omicron SARS-CoV-2 infection by neutralizing antibodies and spike-specific T-cell responses.

OBJECTIVES: The correlate(s) of protection against SARS-CoV-2 remain incompletely defined. Additional information regarding the combinations of antibody and T cell-mediated immunity which can protect against (re)infection is needed. METHODS: We conducted a population-based, longitudinal cohort study including 1044 individuals of varying SARS-CoV-2 vaccination and infection statuses. We assessed spike (S)- and nucleocapsid (N)-immunoglobulin(Ig)G and wildtype, Delta, and Omicron-neutralizing antibody (N-Ab) activity. In a subset of 328 individuals, we evaluated S, membrane (M), and N-specific T cells. Three months later, we reassessed Ab (n = 964) and T cell (n = 141) responses and evaluated factors associated with protection from (re)infection. RESULTS: At the study start, >98% of participants were S-IgG seropositive. N-IgG and M/N-T-cell responses increased over time, indicating viral (re)exposure, despite existing S-IgG. Compared to N-IgG, M/N-T cells were a more sensitive measure of viral exposure. High N-IgG titers, Omicron-N-Ab activity, and S-specific-T-cell responses were all associated with a reduced likelihood of (re)infection over time. CONCLUSION: Population-level SARS-CoV-2 immunity is S-IgG-dominated, but heterogeneous. M/N-T-cell responses can distinguish previous infection from vaccination, and monitoring a combination of N-IgG, Omicron-N-Ab, and S-T-cell responses may help estimate protection against SARS-CoV-2 (re)infection.

Delivering Safe Surgical Care While Simultaneously Caring for Patients With COVID-19; Assessment of Patient Selection, Volume and Outcomes in a Tertiary Care Hospital.

Objectives: Compare patient selection and postoperative outcomes after surgical treatment for gastrointestinal disorders before and during the SARS-CoV-2 pandemic. Methods: We assessed gastrointestinal surgeries conducted at a tertiary center from 2017-2021 for differences in patient populations and procedures before (up to February 2020) and during the pandemic (March 2020 to December 2021). We analyzed mortality, Intensive Care Unit (ICU) length of stay, admission to ICU and postoperative complications for complex procedures using descriptive statistics and regression models. Results: 7309 procedures were analyzed, showing a caseload reduction in March and October 2020, but no statistical evidence for fewer overall procedures overall. Population characteristics differed with lower Body Mass Indices in 2020 and 2021, more patients smoking and with diabetes treated in 2020. There was no increased mortality, ICU length of stay and in 1,144 complex procedures assessed low overall morbidity at 90 days postoperative. Conclusion: Delivering surgical care while treating patients for COVID-19 in the same hospital was safe. Healthcare officials should consider continuing surgical care during future health crises as consequences of limiting surgical treatment for gastrointestinal disorders may be fatal for patients.

Social media and internet search data to inform drug utilization: A systematic scoping review.

Introduction: Drug utilization is currently assessed through traditional data sources such as big electronic medical records (EMRs) databases, surveys, and medication sales. Social media and internet data have been reported to provide more accessible and more timely access to medications' utilization. Objective: This review aims at providing evidence comparing web data on drug utilization to other sources before the COVID-19 pandemic. Methods: We searched Medline, EMBASE, Web of Science, and Scopus until November 25th, 2019, using a predefined search strategy. Two independent reviewers conducted screening and data extraction. Results: Of 6,563 (64%) deduplicated publications retrieved, 14 (0.2%) were included. All studies showed positive associations between drug utilization information from web and comparison data using very different methods. A total of nine (64%) studies found positive linear correlations in drug utilization between web and comparison data. Five studies reported association using other methods: One study reported similar drug popularity rankings using both data sources. Two studies developed prediction models for future drug consumption, including both web and comparison data, and two studies conducted ecological analyses but did not quantitatively compare data sources. According to the STROBE, RECORD, and RECORD-PE checklists, overall reporting quality was mediocre. Many items were left blank as they were out of scope for the type of study investigated. Conclusion: Our results demonstrate the potential of web data for assessing drug utilization, although the field is still in a nascent period of investigation. Ultimately, social media and internet search data could be used to get a quick preliminary quantification of drug use in real time. Additional studies on the topic should use more standardized methodologies on different sets of drugs in order to confirm these findings. In addition, currently available checklists for study quality of reporting would need to be adapted to these new sources of scientific information.

Trajectories of Seroprevalence and Neutralizing Activity of Antibodies against SARS-CoV-2 in Southern Switzerland between July 2020 and July 2021: An Ongoing, Prospective Population-Based Cohort Study.

OBJECTIVES: The COVID-19 pandemic continues, and evidence on infection- and vaccine-induced immunity is key. We assessed COVID-19 immunity and the neutralizing antibody response to virus variants across age groups in the Swiss population. STUDY DESIGN: We conducted a cohort study in representative community-dwelling residents aged five years or older in southern Switzerland (total population 353,343), and we collected blood samples in July 2020 (in adults only, N = 646), November-December 2020 (N = 1457), and June-July 2021 (N = 885). METHODS: We used a previously validated Luminex assay to measure antibodies targeting the spike (S) and the nucleocapsid (N) proteins of the virus and a high-throughput cell-free neutralization assay optimized for multiple spike protein variants. We calculated seroprevalence with a Bayesian logistic regression model accounting for the population's sociodemographic structure and the test performance, and we compared the neutralizing activity between vaccinated and convalescent participants across virus variants. RESULTS: The overall seroprevalence was 7.8% (95% CI: 5.4-10.4) by July 2020 and 20.2% (16.4-24.4) by December 2020. By July 2021, the overall seroprevalence increased substantially to 72.5% (69.1-76.4), with the highest estimates of 95.6% (92.8-97.8) among older adults, who developed up to 10.3 more antibodies via vaccination than after infection compared to 3.7 times more in adults. The neutralizing activity was significantly higher for vaccine-induced than infection-induced antibodies for all virus variants (all p values < 0.037). CONCLUSIONS: Vaccination chiefly contributed to the reduction in immunonaive individuals, particularly those in older age groups. Our findings on the greater neutralizing activity of vaccine-induced antibodies than infection-induced antibodies are greatly informative for future vaccination campaigns.

Joys or Sorrows of Parenting During the COVID-19 Lockdown: A Scoping Review.

Objectives: The aim of this scoping review was to map out the existing evidence of the impact of the COVID-19 lockdown on parents of children and adolescents. We sought to: 1) identify parenting domains that were particularly affected by lockdown measures, 2) describe the challenges and opportunities of lockdown measures in these domains, and 3) define protective and exacerbating factors modulating the effect of lockdown measures on parents. Methods: We identified five main domains investigated in the context of parenting during the early COVID-19 lockdown derived from 84 studies: health and wellbeing, parental role, couple functioning, family and social relationships, and paid and unpaid work. For each domain, we listed challenges and opportunities, as well as discriminant factors. Results: The lockdown impacted all five different but interconnected domains, introduced new roles in parents' lives, and particularly affected women and vulnerable populations. Conclusion: This scoping review highlights the importance of approaching public health policymaking from a social justice perspective. Such an approach argues for social and public health policies to promote health accounting for its social, economic, political, and commercial determinants.

Long COVID Through a Public Health Lens: An Umbrella Review.

Objectives: To synthesize existing evidence on prevalence as well as clinical and socio-economic aspects of Long COVID. Methods: An umbrella review of reviews and a targeted evidence synthesis of their primary studies, including searches in four electronic databases, reference lists of included reviews, as well as related article lists of relevant publications. Results: Synthesis included 23 reviews and 102 primary studies. Prevalence estimates ranged from 7.5% to 41% in non-hospitalized adults, 2.3%-53% in mixed adult samples, 37.6% in hospitalized adults, and 2%-3.5% in primarily non-hospitalized children. Preliminary evidence suggests that female sex, age, comorbidities, the severity of acute disease, and obesity are associated with Long COVID. Almost 50% of primary studies reported some degree of Long COVID-related social and family-life impairment, long absence periods off work, adjusted workloads, and loss of employment. Conclusion: Long COVID will likely have a substantial public health impact. Current evidence is still heterogeneous and incomplete. To fully understand Long COVID, well-designed prospective studies with representative samples will be essential.

Variation in SARS-CoV-2 seroprevalence across districts, schools and classes: baseline measurements from a cohort of primary and secondary school children in Switzerland.

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.

Drivers of Acceptance of COVID-19 Proximity Tracing Apps in Switzerland: Panel Survey Analysis.

BACKGROUND: Digital proximity tracing apps have been released to mitigate the transmission of SARS-CoV-2, the virus known to cause COVID-19. However, it remains unclear how the acceptance and uptake of these apps can be improved. OBJECTIVE: This study aimed to investigate the coverage of the SwissCovid app and the reasons for its nonuse in Switzerland during a period of increasing incidence of COVID-19 cases. METHODS: We collected data between September 28 and October 8, 2020, via a nationwide online panel survey (COVID-19 Social Monitor, N=1511). We examined sociodemographic and behavioral factors associated with app use by using multivariable logistic regression, whereas reasons for app nonuse were analyzed descriptively. RESULTS: Overall, 46.5% (703/1511) of the survey participants reported they used the SwissCovid app, which was an increase from 43.9% (662/1508) reported in the previous study wave conducted in July 2020. A higher monthly household income (ie, income >CHF 10,000 or >US $11,000 vs income ≤CHF 6000 or