Epidemiological evidence of an early wave of the 1918 influenza pandemic in New York City

Olson, Donald R.; Simonsen, Lone; Edelson, Paul J.; Morse, Stephen S.

The 1918 "Spanish flu" was the fastest spreading and most deadly influenza pandemic in recorded history. Hypotheses of its origin have been based on a limited collection of case and outbreak reports from before its recognized European emergence in the summer of 1918. These anecdotal accounts, however, remain insufficient for determining the early diffusion and impact of the pandemic virus. Using routinely collected monthly age-stratified mortality data, we show that an unmistakable shift in the age distribution of epidemic deaths occurred during the 1917/1918 influenza season in New York City. The timing, magnitude, and age distribution of this mortality shift provide strong evidence that an early wave of the pandemic virus was present in New York City during February-April 1918.

Geographic Areas


  • thumnail for Olson_-_Epidemiological_Evidence.pdf Olson_-_Epidemiological_Evidence.pdf application/pdf 382 KB Download File

Also Published In

Proceedings of the National Academy of Sciences of the United Statesof America

More About This Work

Academic Units
National Center for Disaster Preparedness
Published Here
June 21, 2012