It’s hard to think of a symbol of COVID-19 more fraught than the N95 respirator. The mask fits tightly around the face and is capable of filtering 95% of airborne particles, such as viruses, from the air, which other protective equipment (such as surgical masks) can’t do. It’s a life-saving device that is now in dangerously short supply. As such, it has come to represent the extreme challenges of the global response to COVID-19. How did a flimsy polymer cup become the most significant health device of the 21st century? It all started in 1910 with a little-known doctor who wanted to save the world from one of the worst diseases ever known. Read more at Fast Company.