Abstract
In response to significant societal challenges, there is a growing demand for scientists to actively engage in public discussions. The recent Covid-19 pandemic led to the sudden visibility of certain scientists, necessitating them to extend their roles beyond research and actively communicate with the general public. Online platforms allow for direct engagement but increase the challenge by interconnecting different public arenas. Our case study examined the role performance of visible virologists on Twitter/X in six different time periods during the pandemic in Germany (N = 1003). Findings indicate that they often express calls to action, and voice their own views, but seldom address uncertainty. Differences over time were found in their use of different types of statements, scientific jargon and emotional language. They also utilised the opportunities of direct communication, performing roles like watchdogs or advocates, highlighting the importance for scientists to reflect on their roles as communicators.