The impact of the COVID-19 pandemic on vaccine sentiment among Brazilian healthcare workers: A cross-sectional online survey study

Background Vaccine hesitancy (VH) and vaccine sentiment (VS) among healthcare workers (HCWs) play a crucial role in vaccination programs. In response to this global challenge, an international project was initiated to investigate the determinants of VS. Method From 2022 to 2023, an anonymous cross-sectional online survey was disseminated to assess Brazilian HCWs’ characteristics, attitudes, and information sources regarding the COVID-19 vaccine. Five psychological constructs were derived using exploratory factor analysis (EFA), and associated with five VS (vaccination attention, vaccine intention, vaccine confidence, general attitude, and health system confidence) through multivariate logistic regressions. Results The prevalence of VH was low among 634 participants (3.9%), and VS was generally positive. Most HCWs reported strong knowledge confidence (7.3/10), high fear of infection (8.0/10), broad agreement on vaccine necessity (98%), and frequently adopted institutional websites (85.4%) or scientific societies (70.8%) as information sources. Extended from the 5C model, obligated collective responsibility (OCR), representing a professional sense of duty, was significantly associated with vaccine intention, confidence, and attention. Trust in institutional websites emerged as a key determinant of positive VS, while institutional skepticism persisted, especially among HCWs in hospitals, universities, and research settings. “Calculation” was not a significant factor, potentially due to HCWs’ time constraints. Social media, friends, or community members did not significantly link to VS. Conclusions This study identifies key determinants of VS and introduces OCR as a novel expansion to the 5C model. Enhancing VS will require trusted, concise institutional communication and ethics-driven workplace policies that appeal to HCWs’ professional responsibilities.