Caracterização da (Des)Informação das Narrativas sobre Vacinação em Grupos Públicos no WhatsApp no Brasil
Resumo
WhatsApp has become one of the main channels for disseminating health information in Brazil, especially during the COVID-19 pandemic. In this work, we investigate the spread of (mis)information about vaccines in public groups on the platform, focusing on identifying dominant narratives, engagement patterns, and connections to other online information sources. Using a set of 84,640 messages collected between 2020 and 2023, we applied Natural Language Processing (NLP) techniques, including topic modeling (BERTopic) and textual similarity analysis. Overall, the results show that alarmist, misinformative, and politicized content is prevalent, with many messages repeated across multiple groups. We also observed a concentration of activity among a few highly active users, suggesting coordinated amplification strategies. This analysis helps to understand the mechanisms of misinformation spread in private messaging environments and provides insights for public policy and digital health countermeasures.
Palavras-chave:
WhatsApp, Saúde, Vacina, COVID-19, Desinformação, Fake News
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Publicado
10/11/2025
Como Citar
SANTOS, Jônatas H. dos et al.
Caracterização da (Des)Informação das Narrativas sobre Vacinação em Grupos Públicos no WhatsApp no Brasil. In: BRAZILIAN SYMPOSIUM ON MULTIMEDIA AND THE WEB (WEBMEDIA), 31. , 2025, Rio de Janeiro/RJ.
Anais [...].
Porto Alegre: Sociedade Brasileira de Computação,
2025
.
p. 121-130.
DOI: https://doi.org/10.5753/webmedia.2025.15783.
