Flu: The Story of the Great Influenza Pandemic of 1918 and the Search for the Virus That Caused It

by Gina Kolata

How many became ill? More than 25 percent of the U.S. population. What about servicemen, the very young and healthy who were the virus’s favorite targets? The Navy said that 40 percent of its members got the flu in 1918. The Army estimated that about 36 percent of its members were stricken. How many died worldwide? Estimates range from 20 million to more than 100 million, but the true number can never be known. Many places that were bludgeoned by the flu did not keep mortality statistics, and even in countries such as the United States, efforts at tabulating flu deaths were complicated by the fact that there was no definitive test in those days to show that a person actually had the flu. But still, the low end of the mortality estimates is stunning. In comparison, AIDS had killed 11.7 million people through 1997. World War I was responsible for 9.2 million combat deaths and around 15 million total deaths. World War II for 15.9 combat deaths. Historian Crosby remarks that whatever the exact number felled by the 1918 flu, one thing is indisputable: the virus “killed more humans than any other disease in a period of similar duration in the history of the world.”