Spanish flu
In 1918, everyone hoped that the world war was coming to an end. The United States had entered the war, and despite the collapse of the Eastern Front following the conclusion of the Brest-Litovsk peace between Germany and Bolshevik Russia, the conflict was coming to an end, after killing millions. But in January 1918 began the Spanish flu epidemic that would cause, by December 1920, between 50 and 100 million victims. It is said that this epidemic has killed more people in half a year than AIDS in 25 years, and in one year more than bubonic plague in a century.
