Uploaded January 2020 | Updated September 2026, 2 weeks ago
Annual influenza epidemics are estimated to affect 5–15% of the global population. Although most cases are mild, these epidemics still cause severe illness in 3–5 million people and 290,000–650,000 deaths worldwide. The 1918 flu epidemic began with a wave of mild cases in the spring, followed by more deadly waves in the autumn, eventually killing hundreds of thousands in the United States and 50–100 million worldwide.
Annual influenza epidemics are estimated to affect 5–15% of the global population. Although most cases are mild, these epidemics still cause severe illness in 3–5 million people and 290,000–650,000 deaths worldwide. The 1918 flu epidemic began with a wave of mild cases in the spring, followed by more deadly waves in the autumn, eventually killing hundreds of thousands in the United States and 50–100 million worldwide.
