Alexandre R Marra, João Luiz Miraglia, Daniel Tavares Malheiro, Yang Guozhang, Vanessa Damazio Teich, Elivane da Silva Victor, João Renato Rebello Pinho, Adriana Cypriano, Laura Wanderly Vieira, Miria Polonio, Rafael Herrera Ornelas, Solange Miranda de Oliveira, Flavio Araujo Borges, Silvia Cristina Cassiano Oler, Victória Catharina Volpe Ricardo, Aline Miho Maezato, Gustavo Yano Callado, Guilherme de Paula Pinto Schettino, Ketti Gleyzer de Oliveira, Rúbia Anita Ferraz Santana, Fernanda de Mello Malta, Deyvid Amgarten, Ana Laura Boechat, Takaaki Kobayashi, Jorge L Salinas, Michael B Edmond, Luiz Vicente Rizzo
OBJECTIVE: To compare the long-term vaccine effectiveness between those receiving viral vector [Oxford-AstraZeneca (ChAdOx1)] or inactivated viral (CoronaVac) primary series (2 doses) and those who received an mRNA booster (Pfizer/BioNTech) (the third dose) among healthcare workers (HCWs). METHODS: We conducted a retrospective cohort study among HCWs (aged ≥18 years) in Brazil from January 2021 to July 2022. To assess the variation in the effectiveness of booster dose over time, we estimated the effectiveness rate by taking the log risk ratio as a function of time...
2023: Antimicrob Steward Healthc Epidemiol