Previous research has examined learning from crises. However, comparatively neglected is the analysis of learning during such events. This explorative case study reports findings on how learning took place during the outbreak of Escherichia coli in Germany in 2011, which resulted in 53 fatalities. We identify three broad communities: (a) public agencies, (b) research institutions and hospitals and (c) opposition parties and non-governmental organizations. We discuss their conflicting interests in the face of the unfolding crisis, and we explore how their (re)actions and sensemaking affected the way the outbreak progressed. By conceptualizing the crisis as an epistemic object, we show how transepistemic sensemaking both enabled and constrained learning. The crisis, as an epistemic object, is a contested terrain, and each epistemic group’s commitments influenced the trajectory of their responses, demanding a processual perspective to capture the constantly realigning ways actors interpret and react upon the crisis. This study demonstrates how learning during a crisis may thus be transitory since it is hampered by a ‘war for meaning’. This ‘war’ potentially also prevents significant learning subsequent to a crisis, as institutional and epistemic commitments are quickly reformed and transepistemic engagements are closed.