Immunization of 7 Different Vaccines Against SARS-COV-2 Across 4 Countries.

Background: Scarce information exists in relation to the comparison of seroconversion and adverse events following immunization (AEFI) with different SARS-COV2 vaccines. Our aim was to correlate the magnitude of the antibody response to vaccination with previous clinical conditions and AEFI. Methods: A multicentric comparative study where SARS-CoV-2 spike 1-2 IgG antibodies IgG titers are being measured at baseline, 21-28 days after the first and second dose (when applicable), six months and a year of the following vaccines: BNT162b2 mRNA, mRNA-1273, Gam-COVID-Vac, Coronavac, ChAdOx1-S, Ad5-nCoV and Ad26.COV2. Mixed model and Poisson generalized linear models will be performed for the analyses.