The Structural Influence of Low-Credibility Narratives During the COVID-19 Vaccine Rollout
2026-06-01 • Social and Information Networks
Social and Information Networks
AI summaryⓘ
The authors studied how false or misleading stories about COVID-19 vaccines spread on social media, focusing on the difference between bots and human users. They created two new ways to measure how popular and far-reaching these stories are in the network. By analyzing millions of messages, they found that humans shared these messages more effectively than bots overall. However, bots were more influential before vaccines were available, while humans had more impact during the vaccine launch. This shows that bots and humans play different roles at different times when false stories spread online.
low-credibility narrativessocial media influencebotshuman usersnetwork analysisAppeal metricScope metricCOVID-19 vaccine misinformationtemporal stagesX platform
Authors
Lynnette Hui Xian Ng, Wenqi Zhou, Kathleen M. Carley
Abstract
This work examines the structural influence of low-credibility narratives and the comparative role of automated accounts (bots) versus human users on social media platforms. To more accurately quantify the structural influence of a narrative on social media, this study proposes two novel metrics: (1) Appeal, which measures the network-weighted popularity of a message; and (2) Scope, which measures an author's message popularity-weighted network penetration. Applying these metrics, this study analyzes 5.8 million messages from X that contain low-credibility narratives regarding COVID-19 vaccine across three distinct temporal stages: Pre-Vaccine, Vaccine Launch, and Post-Launch. The results demonstrate that across all timeframes, human-distributed low-credibility narratives achieved higher structural influence compared to those generated by automated accounts. Furthermore, statistical analysis reveals a significant conditional temporal effect: human-driven low-credibility narratives attained their highest Appeal and Scope during the focal Vaccine Launch week, whereas automated accounts maximized their Appeal and Scope during the highly uncertain Pre-Vaccine period. These findings highlight the distinct operational capacities of automated and organic accounts, illustrating how the Appeal and Scope of low-credibility narratives is moderated by the lifecycle stages of critical public events.