Spanish Flu Pandemic
The influenza pandemic of 1918–1919 was the deadliest disease event in recorded human history. It spread in three waves: a mild spring wave (spring 1918), a devastating second wave (September–November 1918), and a moderately severe third wave (winter 1918–19). Unlike typical influenza, the second wave killed healthy adults aged 20–40 in large numbers — the very demographic that filled the trenches — through a cytokine storm where the immune system attacked the lungs. The disease killed more American soldiers than combat did. It was misnamed "Spanish Flu" because Spain, neutral and uncensored, was the first country to report it widely; the actual origin remains debated. The pandemic infected an estimated 500 million people — a third of the world's population — and killed between 50 and 100 million, compared with approximately 17 million war deaths. Wartime conditions of mass troop movements, crowded camps, and suppressed reporting facilitated its spread. The pandemic contributed to economic collapse and social upheaval in the war's aftermath, and may have influenced the punitive terms of the Paris Peace Conference, where Woodrow Wilson fell seriously ill during negotiations.
- Year: 1918 CE
- Category: Social
