Professor David Earn is an interdisciplinary scientist who combines mathematical analysis of dynamical systems with detective work on historical disease outbreaks to explore and understand complex epidemic patterns, from the Black Death in the 14th century to the COVID-19 crisis. Throughout the current pandemic, Professor Earn has been deeply involved in real-time assessment and forecasting of infections, hospitalizations, and deaths. He co-leads the Canadian Network for Modelling Infectious Diseases (CANMOD, https://canmod.net) and currently chairs the Ontario COVID-19 Modelling Consensus Table. His research is especially relevant to long-term infectious disease control, and to pandemic preparedness and management.