In the Spring of 1918 a strain of Influenza that had never circulated in the human population before popped up in a group of soldiers training to fight in WW1 in Kansas. They took the virus to Europe with them. At first the infection was limited to the camp where the soldiers lived, and it killed a few hundred people. Not much of entry for a sickness that just a little less than a year later would sweep around the globe killing somewhere between 50 and 100 million people worldwide. Viruses are like the thermonuclear weapons of the biological world. They are mysterious, can strike without warning, and have the potential to cause destruction on a truly terrifying scale.