Specchio-COVID19 cohort study: longitudinal follow-up of participants in seroprevalence surveys in the canton of Geneva

Hélène Baysson, Francesco Pennacchio, Ania Wisniak, Maria Eugenia Zaballa, Nick Pullen, Prune Collombet, Elsa Lorthe, Stéphane Joost, Jean-François Balavoine, Delphine Bachmann, Andrew Azman, Didier Pittet, François Chappuis, Omar Kherad, Laurent Kaiser, Idris Guessous, Silvia Stringhini, for the Specchio-COVID19 study group.
Specchio-COVID19 cohort study: a longitudinal follow-up of SARS-CoV-2 serosurvey participants in the canton of Geneva, Switzerland.. BMJ Open 2022;12:e055515. doi:10.1136/ bmjopen-2021-055515

Summary:

Introduction : The COVID-19 pandemic has affected billions of people worldwide both directly through the infection itself and indirectly through its health, economic, and social impacts. Data collection over time is essential to understand the spread of COVID-19 disease, the incidence of symptoms suggestive of SARS-CoV-2 infection, the level and dynamics of immunity, and the long-term impact of the pandemic. The aim of the study was to set up a longitudinal follow-up of adult participants in serological surveys carried out in the canton of Geneva during the COVID-19 pandemic. The aim of this longitudinal follow-up was to monitor the incidence of symptoms and seroconversion, as well as the overall impact of the pandemic on several dimensions of health and on socio-economic factors over a period of at least 2 years.

Methods and analyses: Participants in the serological survey were invited to create an account on the Specchio-COVID19 digital platform. On registration, an initial questionnaire was designed to assess socio-demographic and lifestyle characteristics (including housing conditions, physical activity, diet, alcohol and tobacco consumption), anthropometry, general health status and experience of COVID-19 (symptoms, results of COVID-19 screening tests, quarantines, hospitalisations). Each week, participants were asked to complete a short questionnaire about any symptoms they had consistent with SARS-CoV- 2 infection, the results of their screening tests and their vaccination status. A more detailed questionnaire on mental health, well-being, perception of risk and changes in working conditions was offered on a monthly basis. Additional questionnaires were administered at regular intervals to measure the impact of the pandemic on physical and mental health, vaccine adherence, healthcare consumption and changes in health behaviour. At inclusion, serological tests were used to assess the spread of SARS-CoV- 2 infection among the general population and subgroups of workers. In addition, seropositive participants and a randomly selected sample of participants were invited for serological testing at regular intervals in order to monitor both the seropersistence of anti-SARS-CoV-2antibodies and changes in the seroprevalence rate in the canton of Geneva.

Link to the article in English