Temporal trends of COVID-19 antibodies in vaccinated healthcare workers undergoing repeated serological sampling : An individual-level analysis within 13 months in the ORCHESTRA cohort - Collatuzzo, Giulia (Department of Medical and Surgical Sciences, University of Bologna) ; De Palma, Giuseppe (University of Brescia) ; Violante, Francesco S. (University of Verona) ; Larese Filon, Francesca (University of Trieste) ; Fabianova, Eleonora (Regional Authority of Public Health) ; Violán, Concepció (Universitat Autònoma de Barcelona) ; Vimercati, Luigi (University of Bari) ; Leustean, Mihaela (National Institute of Public Health) ; Rodriguez-Suarez, Marta Maria (Universidad de Oviedo) ; Sansone, Emanuele (IRCCS Azienda Ospedaliero-Universitaria di Bologna) ; Sala, Emma (ASST Ospedali Civili di Brescia) ; Zunarelli, Carlotta (Universidad de Bologna) ; Lodi, Vittorio (IRCCS Azienda Ospedaliero-Universitaria di Bologna) ; Monaco, Maria Grazia Lourdes (University Hospital of Verona (Itàlia)) ; Spiteri, Gianluca (University Hospital of Verona (Itàlia)) ; Negro, Corrado (Unit of University of Trieste) ; Beresova, Jana (Regional Authority of Public Health) ; Carrasco-Ribelles, Lucia Amalía (Institut Universitari d'Investigació en Atenció Primària Jordi Gol) ; Tafuri, Silvio (Interdisciplinary Department of Medicine, University of Bari) ; Asafo, Shuffield S. (Department of Medical and Surgical Sciences, University of Bologna) ; Ditano, Giorgia (Department of Medical and Surgical Sciences, University of Bologna) ; Abedini, Mahsa (Department of Medical and Surgical Sciences, University of Bologna) ; Boffetta, Paolo (Stony Brook University)