The 1918-1919 influenza outbreak was the most deadly in human history (in absolute numbers; the 14th-century plague killed more people as a percentage of population). Estimates range from 20 to as high as 100 million dead. The high degree of uncertainty has to do with the global nature of the outbreak, with remote areas such as the Arctic being the most uncertain.
As the author explains,
Influenza killed more people in a year than the Black Death… killed in a century; it killed more people in 24 weeks than aids killed in 24 years. (p. 5)
Two factors made the pandemic especially devastating. First, it came on the heels of the Great War. In fact, war and disease have historically been close bedfellows–disease killed more U.S. soldiers than combat before the 1950’s. War brings people into close quarters, both troops in their barracks and transports, as well as support workers in urban settings. Conflict also causes travel of distances that are historically unusual, both for soldiers and displaced civilians.
The second reason for the flu’s historical impact was that many of its victims were young adults. Typically most influenza casualties are the very young or the elderly. By killing people in the prime of their lives, they were “doubly dead,” as one observer put it.
In this book, the author argues convincingly for one origin tale of the outbreak. He shows how it likely originated at a military camp in Kansas in March, 1918. From their, it spread via troops trains and ships, and by the fall of that year had become a global disease. A second outbreak in spring, 1919, took even more lives. In the American military alone, the disease caused more deaths than all Americans killed in combat in Vietnam (p. 239.)
The social response mostly involved banning public gatherings, including religious services. Different cities responded with different degrees of urgency. Boston was very proactive. Philadelphia was in a state of denial. Gunnison, Colorado, isolated itself, its citizens keeping outsiders at bay by threatening them at gunpoint.
Civilian response was complicated by the fact of wartime censorship. Bad news was “unpatriotic,” so early warnings about the pandemic were silenced. In fact, this is why the outbreak is known as “Spanish influenza”: Spain remained neutral during the war, so outbreaks there were reported widely and early (p. 171).
This is an important book for students of history, science, and politics. Most instructive is how such an outbreak might still occur today.