Dr. Yanina Purim-Shem-Tov shoulders a lot as she helps lead the emergency department at Rush University Medical Center amid the coronavirus crisis. The grueling 70-hour workweeks. An ever-evolving understanding of COVID-19. Her husband moving into the guest room to reduce the chance of a possible transmission. Purim-Shem-Tov accepts it all with an unflustered shrug, confident in the knowledge that her department — the entire hospital, really — was built for this exact moment.