Piedrahita-Castillo, J. Bermejo-Higuera, J.R. Bermejo-Higuera, Sicilia- Montalvo, Machío-Regidor); European University of Valencia (
P. Guillem- Saiz); Institute of Health Carlos III (
P. Guillem-Saiz); International University of Valencia (
J. Guillem-Saiz) The emergence of the Internet as a key source of vaccine-related content.has made it essential to incorporate online information monitoring in the strategies for addressing vaccine hesitancy. Social media sites allow users from different countries to have public discussions about any topic, including vaccination, in real time. In the context of concerns about the increase in misinformation and rumours spreading online, social media can serve not only as communication tool for global health actors but also a platform for real-time surveillance of vaccine hesitancy. Sentiment analysis (SA) is a text-mining subfield that allows for the classification of opinions according to the polarity (positive, negative, or neutral), th