(author note: this pic is from a photo archive of Spanish Flu victims. One of the dangerous aspects of this epidemic is that it could kill within hours, even a young, healthy subject.)
This article explores the 1918-1919 Spanish Flu Epidemic. It offers some historical, medical, and social insight on one of the most virulent strains of pathogens to take down a significant portion of the population. Apparently, the battle against misinformation is an on-going one.