Condition category
Infections and Infestations
Date applied
09/07/2020
Date assigned
13/07/2020
Last edited
26/10/2020
Prospective/Retrospective
Retrospectively registered
Overall trial status
Ongoing
Recruitment status
Recruiting

Plain English Summary

Background and study aims
The increasing number of persons diagnosed with a SARS-CoV-2 infection in February and March 2020 and the subsequent Swiss Federal Council's measures had major implications for public life and for the economy. For guidance after these measures have lifted and for future policy decisions on how to minimize the disease and societal burden of SARS-CoV-2 reliable epidemiological data is needed. The knowledge of the nation-wide prevalence of SARS-CoV-2 infection at the level of the population, in different geographical areas and of specific age groups is required. This knowledge will also help prepare future outbreak responses and is important to inform future vaccination strategies.

In a number of Swiss Cantons, studies on the seroprevalence of SARS-CoV-2 antibodies and the extent and duration of immunity are planned or have already started. The interest for such epidemiological studies comes from both Cantonal authorities and scientists who want to learn about the seroprevalence of SARS-CoV-2 antibodies, both in the general population (across age ranges) and in specific groups of persons (e.g. nursing home residents, working in specific sectors of economy, from citizens, etc.).

The scientists of the Swiss School of Public Health (SSPH+) have agreed to coordinate their effort in order to make their data as comparable as possible, to create synergies and reduce redundancies. The goal is to make the studies informative for policy makers on the national and Cantonal level while fully respecting the autonomy of the Cantons and scientists involved. SSPH+ is committed to shed light on the extent of the spread of SARS-CoV-2, as quickly as possible, in Switzerland, and has launched an initiative with the aim of acquiring funding from public and private sources (https://www.corona-immunitas.ch/).

The aim of this study is to determine the extent and nature of infection with SARS-CoV-2 in the general population and in specific subgroup in different Cantons of Switzerland, after the first major wave and in further epidemic phases of SARS-CoV-2, and to contribute to consistent estimates in the Swiss population.

Who can participate?
All persons who are invited to participate in the study (randomly selected participants from the general population and specific sub-populations).

What does the study involve?
Study participation includes 1) the completion of the baseline questionnaire; 2) the collection of a peripheral blood sample by venipuncture for determination of SARS-CoV-2 antibodies at a study center, a mobile unit or the participant’s home; and 3) the invitation to fill-in a weekly and monthly digital follow-up questionnaire for the next 6 to 12 months.
Specific sub-populatiopns of participants will be re-invited for repeated blood collection for SARS-CoV-2 antibody tests, where the same procedures will be used.

What are the possible benefits and risks of participation?
The primary benefit of the study is indirect. The evaluation of the SARS-Cov-2 seroprevalence in the general population and specific subgroups is essential to understand what phase of the epidemic we are currently in, to be able to make predictions for the continuation of the epidemic and to put in place adequate public health measures. It will also provide information on the proportion of oligo- and asymptomatic cases. The publication of these results as open access will be useful to the entire international scientific community as well as other stakeholders including guideline developers, policy makers and physicians.

The risk associated with the collection of blood samples is very low. Possible complications are minor and include a hematoma at the puncture site, infection, or vagal discomfort during blood collection. All safety measures will be taken to prevent these complications from occurring by adopting standard collection rules and working with registered nurses. There is also a risk of SARS-CoV-2 infection on the way from participants' homes to the study centers and during contact at the study site. We have tried to minimize this risk; during all interactions, study staff will follow current standard hygiene procedures (hand washing and disinfection procedures, wearing masks and gloves) and participants will wear a mask, provided by the study staff. The mobile investigation teams who travel to conduct the study visit at the participants’ home will follow the same procedures.

Where is the study run from?
Swiss School of Public Health (SSPH+), an inter-university faculty that unites twelve Swiss universities, coordinates nationwide the seroprevalence studies. The responsible study centers in the participating Swiss Cantons run the studies.

When is the study starting and how long is it expected to run for?
From April 2020 until Spring 2021.

Who is funding the study?
Corona Immunitas is funded by several sources: All: by fundraising of SSPH+ that includes funds of the Federal Office of Public Health and private funders (foundations, companies and private donations; ethical guidelines for funding stated by SSPH+ will be respected); center specific by funds of the Cantons, by institutional funds of the Universities and by other center-specific sources.

Who is the main contact?
Prof. Dr. med. et phil. Milo A. Puhan, miloalan.puhan@uzh.ch

Trial website

https://www.corona-immunitas.ch/

Contact information

Type

Scientific

Primary contact

Prof Milo Puhan

ORCID ID

https://orcid.org/0000-0003-4721-1879

Contact details

Epidemiology
Biostatistics and Prevention Institute
University of Zurich
Hirschengraben 84
Zurich
8001
Switzerland
+41 44 634 46 10
miloalan.puhan@uzh.ch

Type

Public

Additional contact

Prof Jan Fehr

ORCID ID

https://orcid.org/0000-0003-1113-9895

Contact details

Epidemiology
Biostatistics and Prevention Institute
University of Zurich
Hirschengraben 84
Zurich
8001
Switzerland
+41 44 634 46 79
jan.fehr@uzh.ch

Type

Scientific

Additional contact

Dr Anja Frei

ORCID ID

https://orcid.org/0000-0002-7134-1000

Contact details

Epidemiology
Biostatistics and Prevention Institute
University of Zurich
Hirschengraben 84
Zurich
8001
Switzerland
+41 44 634 43 60
anja.frei@uzh.ch

Additional identifiers

EudraCT number

Nil known

ClinicalTrials.gov number

Nil known

Protocol/serial number

Nil known

Study information

Scientific title

Seroprevalence of SARS-CoV-2 antibodies and development of immunity in the Swiss population – Multicenter population-based observational studies to inform policy making

Acronym

Corona Immunitas

Study hypothesis

The main goal of the Corona Immunitas research program is to determine the extent and nature of infection with SARS-CoV-2 in all regions of Switzerland in a highly consistent and comprehensive way in the general Swiss population as well as particularly exposed and vulnerable groups. Specific aims are to: 1) quantify the number of individuals infected with SARS-CoV-2 in the population with or without symptoms at several points in time; 2) compare the seroprevalence between the general population and specific subpopulations; 3) investigate the nature and extent of immunity after infection; 4) assess the association between participant characteristics and behaviors with infection; and 5) quantify the impact of the pandemic on mental and physical health. Most importantly, this evidence-based program aims to provide policy-makers and other decision makers with important evidence for deciding which public health and setting-specific measures to implement or lift for the general population and specific subpopulations at different points in time.

Ethics approval

Approved 28/05/2020, Cantonal Ethics Committee Zurich (Stampfenbachstrasse 121, CH-8090 Zurich, Switzerland; +41 43 259 79 70; Info.KEK@kek.zh.ch), ref: 2020-01247

Study design

A group of prospective observational cohort studies

Primary study design

Observational

Secondary study design

Cohort study

Trial setting

Community

Trial type

Diagnostic

Patient information sheet

See additional files

Condition

SARS-CoV2 infection (COVID-19)

Intervention

Potential participants are either randomly selected from the general population or selected from specific sub-population settings. The process of enrollment is organized by each study center and for each population individually. Generally, potential participants are informed and invited to participate in the study by postal mail or email and asked to schedule an appointment for a study visit either at a study center, at a mobile unit (bus) or at their home (vulnerable persons). Before the study visit, participants are provided with the link to an online baseline questionnaire asking demographic questions, symptoms, other tests taken for SARS-CoV-2, preventative measure behaviors and quality of life measures.

After providing informed consent, the study visit is conducted by trained study personnel. The expected duration of the visit is 20-30 minutes in total and data is assessed in three stages:
1) Study staff checks the completeness of the baseline questionnaire and, if incomplete, advises the participant to complete it on a computer, tablet or on paper/pencil.
2) Trained health care staff collects a peripheral blood sample by venipuncture for the determination of SARS-CoV-2 antibodies (quantity varies according to study site). The participants are explained orally and by a leaflet how to interpret a positive serological test result (probability that result is inaccurate) and are instructed to keep on following the recommendations of the public health authorities, regardless of their individual test result. The entire sequence from blood withdrawal to storage and testing follows a Standardized Operating Procedure.
3) Participants are invited to fill-in a weekly and monthly digital follow-up questionnaire for the next 6 to 12 months, capturing health status, symptoms and behaviors over time..

Specific groups of participants will be re-invited for repeated blood collection for SARS-CoV-2 antibody testing, once or several times.

Intervention type

Other

Phase

Drug names

Primary outcome measure

Seroprevalence of SARS-CoV-2 antibodies measured using peripheral blood sample by venipuncture in the general population and in specific subpopulations at repeated time points during the epidemic in Switzerland

Secondary outcome measures

1. Presence of symptoms suggestive of a common cold, influenza and similar upper respiratory tract infections prior to the first study visit. Measured by baseline questionnaire (at baseline)
2. Potential risk factors and preventive measures for SARS-CoV-2 infection (exposure, socio-economic factors, adherence to general hygiene and physical distancing rules, utilization of mask and gloves). Measured by baseline questionnaire (at baseline)
3. Incidence of self-reported symptoms and SARS-CoV-2 infections after the first study visit in initially seropositive individuals (extent and duration of immunity after infection with SARS-CoV-2). Measured by digital follow-up questionnaire (weekly)
4. Proportion of seronegative individuals of the first investigation wave who will self-report symptoms and infection with SARS-CoV-2. Measured by digital follow-up questionnaire (weekly)
5. Course over time in access to health care, health care renunciation, going outside (frequency, reason, physical activity), preventive measures with respect to COVID-19. Measured by digital follow-up questionnaire (weekly and monthly)
6. Course over time in mental well-being, specifically stress, anxiety and depression. Measured by digital follow-up questionnaire (monthly)

Overall trial start date

18/03/2019

Overall trial end date

31/12/2021

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. No acute SARS-CoV-2 infection: no presence of symptoms for at least 48 hours
2. In case of a SARS-CoV-2 infection verified by a RT-PCR test, the earliest inclusion is 21 days after the test date

Participant type

All

Age group

All

Gender

Not Specified

Target number of participants

In the frame of Corona Immunitas, it is planned to include around 25,000 participants in the different Cantons / centers of Switzerland.

Participant exclusion criteria

1. No informed consent
2. Suspicion of acute COVID-19 infection

Recruitment start date

01/04/2020

Recruitment end date

31/12/2020

Locations

Countries of recruitment

Switzerland

Trial participating centre

University of Zurich
Epidemiology, Biostatistics and Prevention Institute Hirschengraben 84
Zurich
8001
Switzerland

Trial participating centre

University of Fribourg
Population Health Laboratory Department of Community Health Faculty of Science and Medicine Route des Arsenaux 41
Fribourg
1700
Switzerland

Trial participating centre

Università della Svizzera Italiana
Institute of Public Health Via G. Buffi 13
Lugano
6900
Switzerland

Trial participating centre

Unisanté Lausanne
Department of Health and Social Action Avenue des Casernes 2
Lausanne
1014
Switzerland

Trial participating centre

Geneva University Hospitals
Division of Primary Care Rue Gabrielle-Perret-Gentil 4
Geneva
1205
Switzerland

Trial participating centre

Swiss Tropical and Public Health Institute
Department of Epidemiology and Public Health Socinstrasse 57
Basel
4051
Switzerland

Trial participating centre

Service cantonal de la Santé Publique de Neuchâtel
Beaux-Arts 13
Neuchâtel
2000
Switzerland

Sponsor information

Organisation

Swiss School of Public Health

Sponsor details

SSPH+ Foundation
Prof. Dr. med et PhD Nino Künzli
Hirschengraben 82
Zurich
8001
Switzerland
+41 44 634 47 02
info@ssphplus.ch

Sponsor type

University/education

Website

https://ssphplus.ch/

Funders

Funder type

Government

Funder name

Fundraising of SSPH+ that includes funds of the Bundesamt für Gesundheit (Federal Office of Public Health, Switzerland)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Funder name

Fundraising of SSPH+ that includes funds of private funders (ethical guidelines for funding stated by SSPH+ are respected)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Funder name

Center specific: Institutional funds and funds provided by the Cantons (public funds)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Results will be published in high-impact peer-reviewed scientific journals.

IPD sharing statement:
The current data sharing plans for this study are unknown and will be available at a later date

Intention to publish date

31/03/2021

Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

2020 early results in https://www.doi.org/10.1016/S0140-6736(20)31304-0 (added 09/07/2020)
2020 protocol in https://pubmed.ncbi.nlm.nih.gov/33098441/ (added 26/10/2020)

Publication citations

Additional files

Editorial Notes

26/10/2020: Publication reference added. 07/08/2020: The participant information sheet was uploaded as an additional file. 10/07/2020: Trial’s existence confirmed by Cantonal Ethics Committee Zurich.