Measuring the co-evolution of online engagement with (mis)information and its visibility at scale

Online attention is an increasingly valuable resource in the digital age, with extraordinary events such as the COVID-19 pandemic fuelling fierce competition around it. As misinformation pervades online platforms, users seek credible sources, while news outlets compete to attract and retain their attention. Here we measure the co-evolution of online "engagement" with (mis)information and its "visibility", where engagement corresponds to user interactions on social media, and visibility to fluctuations in user follower counts. Using a scalable temporal network modelling framework applied to over 100 million COVID-related retweets spanning 3 years, we find that highly engaged sources experience sharp spikes in follower growth during major events (e.g., vaccine rollouts, epidemic severity), whereas sources with more questionable credibility tend to sustain faster growth outside of these periods. Our framework lends itself to studying other large-scale events where online attention is at stake, such as climate and political debates.