Incidence and risk factors related to SARS-CoV-2 infection, reinfection, and seroconversion: Analysis of a healthcare workers cohort from a university hospital in Colombia

OBJECTIVES: To determine the incidence and factors associated with SARS-CoV-2 infection and seroconversion among healthcare workers (HCWs) during the COVID-19 pandemic in a university hospital in Colombia. METHODS: We analyzed the CoVIDA-Fundación Santa Fe de Bogotá (FSFB) cohort, consisting of 419 HCWs from the FSFB university hospital. The cohort was followed during active surveillance (June 25, 2020, to April 30, 2021) and passive surveillance (May 01, 2021, to March 16, 2022) periods. Incidence rates for SARS-CoV-2 infection, reinfection, and seroconversion were estimated, considering pre- and post-COVID-19 vaccination. Cox proportional-hazards models were used to identify factors related to infection and seroconversion during the active surveillance period. RESULTS: COVID-19 incidence rate ranged between 16-52 cases per 1000 person-month. SARS-CoV-2 reinfections were rare, ranging between less than one case to 13 cases per 1000 person-month. The seroconversion rates ranged between 52-55 cases per 1000 person-month. High socioeconomic level was a protective factor for SARS-CoV-2 infection, while SARS-CoV-2 infection was the main factor associated with seroconversion. CONCLUSION: This study provides insights into the incidence and risk factors of SARS-CoV-2 infection among HCWs in a Colombian university hospital. The findings may offer valuable guidance for reducing virus spread within healthcare settings.