Trajectories of seroprevalence and neutralizing activity of antibodies against SARS-CoV-2 in Southern Switzerland between July 2020 and July 2021

Amati, Rebecca; Piumatti, Giovanni; Franscella, Giovanni; Buttaroni, Peter; Camerini, Anne-Linda; Corna, Laurie; Levati, Sara; Fadda, Marta; Fiordelli, Maddalena; Annoni, Anna Maria; Bezani, Kleona; Amendola, Antonio; Fragoso Corti, Cristina; Sabatini, Serena; Kaufmann, Marco; Frei, Anja; Puhan, Milo Alan; Crivelli , Luca; Albanese, Emiliano

doi:10.3390/ijerph20043703

Back

Albanese_2023_MDPI_ijerph_Trajectories of seroprevalence

Journal article

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

Amati, Rebecca ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Piumatti, Giovanni Fondazione Agnelli, Italy
Franscella, Giovanni Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Buttaroni, Peter Facoltà di scienze informatiche, Università della Svizzera italiana, Svizzera
Camerini, Anne-Linda ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Corna, Laurie Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Switzerland
Levati, Sara Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Switzerland
Fadda, Marta ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Fiordelli, Maddalena ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Annoni, Anna Maria Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Bezani, Kleona Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Amendola, Antonio Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Switzerland
Fragoso Corti, Cristina Institute of Microbiology, University of Applied Sciences and Arts of Southern Switzerland, Bellinzona, Switzerland
Sabatini, Serena ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland
Kaufmann, Marco Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
Frei, Anja Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
Puhan, Milo Alan Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Switzerland
Crivelli , Luca ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland - Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno, Switzerland
Albanese, Emiliano ORCID Institute of Public Health (IPH), Università della Svizzera italiana, Switzerland

2023

Published in:

International Journal of Environmental Research and Public Health. - 2023, vol. 20, p. 3703

English 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.

Collections

Language