A history of the 1918 Spanish influenza pandemic and its impact on Iran.

Approximately ninety two years ago, the worst influenza pandemic or "Spanish flu" occurred in 1918, at the end of the First World War (WWI, 1914-1918) which resulted in the deaths of millions of people worldwide. The death toll exceeded the total number of victims of WWI. The 1918 Spanish flu was a deadly, major global event that affected many countries, including Iran. In Iran, it was accompanied by a high mortality rate estimated to be more than one million. However, detailed information on the impact of this outbreak in Iran is scarce. The present paper describes a brief history of the influenza pandemics in the world as well as the spread of the 1918 Spanish flu to Iran.