From Whispers to Roars: The Temporal Evolution of Anti-Vaccine Narratives on Telegram

• Fernando H. M. de Oliveira UPE
• Cleyton M. de O. Rodrigues UPE

DOI: https://doi.org/10.5753/webmedia.2026.30814

Resumo

Vaccine-related misinformation on instant messaging platforms like Telegram represents a dynamic threat to public health, requiring computational tools to detect emerging narratives before they reach discursive saturation. This study implements and validates the BERTrend framework to monitor and predict the temporal evolution of vaccine-related discourse within Brazilian public Telegram channels. We analyzed a longitudinal corpus of approximately 330,000 Portuguese-language text messages spanning March 2020 to June 2025. Topics were extracted weekly, then classified into strong or weak signals using adaptive popularity percentiles. Qualitative analysis revealed a progression in rhetorical sophistication across macro-narratives, transitioning from early clinical and mandate concerns (2020–2021) to complex pseudo-scientific, genomic, and globalist conspiracy theories (2024–2025). Under out-of-sample temporal testing, our predictive model demonstrated outstanding performance, showing that emerging weak signals exhibiting immediate subsequent growth were 43.46 times more likely to consolidate into dominant strong signals. We identified a median transition latency of just two weeks between signal emergence and narrative consolidation, establishing an actionable window for early public health intervention.

Palavras-chave: Vaccine Hesitancy, Information Disorder, Topic Modeling, Public Health Surveillance, Social Media Analytics

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