endIndex: (CNN) — A widespread sense that time has split into two — or pandemics creating a "before" and 'after' — is an experience that's associated with many traumatic events. That's the reflection of Elizabeth Outka, a professor of English at the University of Richmond and author of "Viral Modernism: The Influenza Pandemic and Interwar Literature." This social phenomenon is both psychologically and practically relevant, in that pandemics -- including the 1918 influenza and COVID-19 pandemics -- significantly affect how we assess and act on risk, or stay resilient, but also how we work, play and socialize. The startling and harrowing nature of the 1918 flu and its fatal consequences induced a sense of caution that, in some places, had permanent implications for how people would respond to disease outbreaks in later decades -- such as using isolation and quarantine, according to a 2010 paper by Nancy Tomes, a distinguished professor of history at Stony Brook University.