In spring of 1918, World War I was underway, and troops at Fort Riley, Kansas, found themselves felled by influenza. By the summer of 1918, the second wave struck as a highly contagious and lethal epidemic and within weeks exploded into a pandemic, an illness that travels rapidly from one continent to another. It would impact the course of the war, and kill many millions more soldiers than warfare itself. Of all diseases, the 1918 flu was by far...

"Already contacts between virus-carrying animals and humans are increasing due to loss of habitat, population growth, climate change, and other factors. Global travel means that an outbreak can race around the world within weeks. A sudden outbreak like COVID-19 can overwhelm the richest nations and leave their health systems struggling to catch up. And poorer countries can face health crises that quickly spiral out of control. The variety of possible...