Economy of the United States in the 1920s
The Spanish flu pandemic lasted from 1918 to 1920. It killed between 17 million and 100 million people. Symptoms in 1918 were so unusual that initially influenza was misdiagnosed as dengue, cholera, or typhoid. One observer wrote "One of the most striking of the complications was haemorhage from mucous membranes, especially from the nose, stomach, and intestine". Most deaths were from bacterial pneumonia, a secondary infection caused by influenza. The virus also killed people directly. It caused hemorrhages and oedema in the lungs.