Objective: To estimate the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through antibody detection among healthcare personnel (HP) in Gran Santa Fe (Argentina) during virus sustained circulation and remission phases. Materials and methods: A longitudinal, population-based, seroepidemiological study was conducted. The target population consisted of HP working in second- and third-level public health centers in the Gran Santa Fe region. The sample comprised 600 active health workers, proportionally distributed across selected health centers. A self-administered questionnaire collected data on sociodemographic, occupational, clinical and exposure variables of interest. IgG and IgM antibodies to SARS-CoV-2 were detected from serum samples using indirect enzyme-linked immunoassays. Results: The prevalence of IgG antibodies to SARS-CoV-2 was 7.6 times hi...