Effectiveness and safety of COVID-19 vaccines in healthcare workers in Buenos Aires City, Argentina.

Abstract

COVID-19 vaccination aids pandemic limitation. In Argentina, three vaccines are approved, and healthcare workers are priorized (HCWs). The aim was to determine the effectiveness of COVID-19 vaccines, analyzing change in Immunoglobulin G levels and the incidence of new COVID-19 cases up to 12 months after the second dose. Prospective cohort of HCWs between March 2021- 2022. COVIDAR IgG test was used to measure antibodies. A mixed-effects model was employed to compare the levels of immunoglobulin G at different time points, Kaplan Meier was used to estimate incident COVID-19 cases. 82 participants were included Adverse events were frequent but mild. All participant showed positive antibody at 12 months. Antibodies levels showed an increase one year after 2nd dose. Sinopharm took a long time to yield positive results. More than half of the people had mild COVID-19 disease. COVID-19 vaccines are safe and effective.