1918 Pandemic Influenza: Three Waves

https://www.cdc.gov/flu/pandemic-resources/1918-commemoration/three-waves.htm

 There were 3 different waves of illness during the pandemic, starting in March 1918 and subsiding by summer of  1919. The pandemic peaked in the U.S. during the second wave, in the fall of 1918. This highly fatal second wave was responsible for most of the U.S. deaths attributed to the pandemic.