Brazilian Social Media Anti-vaccine Information Disorder Dataset -- Telegram (2020-2025)
João Phillipe Cardenuto, Ana Carolina Monari, Michelle Diniz Lopes, Leopoldo Lusquino Filho, Anderson Rocha
TL;DR
The study tackles the rise of vaccine hesitancy in Brazil driven by online misinformation by constructing a large-scale Telegram dataset collected from 119 public anti-vaccine channels spanning 2020–2025. It employs a Telethon-based data collection pipeline, language identification, and a Portuguese prompt-driven LLM (Sabiá-3) to label vaccine-related content, resulting in a dataset of nearly 4 million posts with rich metadata and media links. The contribution includes a detailed data schema, anonymization and ethical safeguards, and open data access under CC BY-NC 4.0, enabling NLP, social science, and network-analysis research to understand and counter misinformation. The work provides a foundation for evidence-based, empathetic public health communication and policy design to counter vaccine misinformation in Brazil and similar contexts.
Abstract
Over the past decade, Brazil has experienced a decline in vaccination coverage, reversing decades of public health progress achieved through the National Immunization Program (PNI). Growing evidence points to the widespread circulation of vaccine-related misinformation -- particularly on social media platforms -- as a key factor driving this decline. Among these platforms, Telegram remains the only major platform permitting accessible and ethical data collection, offering insight into public channels where vaccine misinformation circulates extensively. This data paper introduces a curated dataset of about four million Telegram posts collected from 119 prominent Brazilian anti-vaccine channels between 2020 and 2025. The dataset includes message content, metadata, associated media, and classification related to vaccine posts, enabling researchers to examine how false or misleading information spreads, evolves, and influences public sentiment. By providing this resource, our aim is to support the scientific and public health community in developing evidence-based strategies to counter misinformation, promote trust in vaccination, and engage compassionately with individuals and communities affected by false narratives. The dataset and documentation are openly available for non-commercial research, under strict ethical and privacy guidelines at https://doi.org/10.25824/redu/5JIVDT
