The so-called âSpanishâ influenza virus seems to have to originate from Haskell County, Kansas. World War I gave rise to ideal conditions for a viral pandemic through overcrowded military camps around the world and the massive transfer of military personnel. Unlike other viral pandemics, the Spanish influenza selectively killed young people at an astonishing speed. The Spanish influenza had three waves, of which the second wave was most severe, causing several million deaths. It swamped many large cities around the world, as well as military camps. The influenza virus uses two proteinsâhemagglutinin and neuraminidaseâto invade cells and replicates through insertion of the viral genome into the invaded cell nuclei. An influenza pandemic generally develops when a radical change in these two proteins occurs through antigen drift. There were no effective treatments or preventive methods during the Spanish influenza pandemic. No authorities, including governments or cities, presented effective guidelines to prevent the spread of the virus, and they sometimes even misled the populace through absolute media control during World War I. The virulence of the virus finally abated by way of âreturning to the mean.â Key words: Spanish influenza; Pandemics; World War I.