Risk assessment and seroprevalence of SARS-CoV-2 infection in healthcare workers of COVID-19 and non-COVID-19 hospitals in Southern Switzerland oleh Luca Piccoli, Paolo Ferrari, Giovanni Piumatti, Sandra Jovic, Blanca Fernandez Rodriguez, Federico Mele, Isabella Giacchetto-Sasselli, Tatiana Terrot, Chiara Silacci-Fregni, Elisabetta Cameroni, Stefano Jaconi, Nicole Sprugasci, Istvan Bartha, Davide Corti, Mariagrazia Uguccioni, Antonio Lanzavecchia, Christian Garzoni, Olivier Giannini, Enos Bernasconi, Luigia Elzi, Emiliano Albanese, Federica Sallusto, Alessandro Ceschi