Beliefs in misinformation about COVID-19 and dengue ina sample ofthe Rio de Janeiro State

Given the ongoing dengue epidemic in Rio de Janeiro (RJ) and the prevalence of misinformation related to COVID-19 anddengue, this study aims to: 1) compare belief levels in COVID-19 and dengue misinformation; 2) examine associations between sociodemographic factors, health-related outcomes, and misinformation beliefs; and 3) explore the reasons underlying these beliefs among residents of Rio de Janeiro. A cross-sectional opinion online survey was conducted using quantitative and qualitative data retrieved from 180 adults who live in RJ.Participants answeredaself-report questionnaireabout sociodemographic and health-related outcomes. Next, they rated as true or false and inform why they believe or not in six misinformation.Our findings reveal higher levels of belief inCOVID-19 compared to dengue misinformation among the Rio de Janeiro population.Furthermore,for each unity increase in number of receivedCOVID-19 vaccine doses,there is an increase of 277% in the odds of the individualsnot believing in misinformation about COVID-19.Individuals with right-wing political affiliations and those opposed to child vaccination exhibited a moderate to strong propensity to believe in misinformation.Trust in vaccines and health professionals emerged as primary determinants of belief in misinformation.