Academy of Medical Sciences of I.R. Iran Archives of Iranian Medicine 1029-2977 25 1 2022 01 01 Spanish Flu in Tehran from 1918 to 1920 71 75 10.34172/aim.2022.10 EN Seyyed Alireza Golshani https://orcid.org/0000-0003-1635-4578 Mohammad Ebrahim Zohalinezhad https://orcid.org/0000-0002-5538-8247 Fatemeh Amoozegar https://orcid.org/0000-0002-4092-2013 Mojtaba Farjam https://orcid.org/0000-0002-9705-2143 Journal Article 10.34172/aim.2022.10 2021 04 05 2021 09 22 The Spanish flu spread from September 23, 1918 to 1920. This disease was one of the historical catastrophes in Iran, and a large number of people in Tehran were infected. Evidence also shows that 5000–10000 out of the 250000 infected people died in Tehran over three years. Besides, an increase was detected in the prevalence of other diseases such as pericarditis, orchitis, mastoiditis, meningitis, optic neuritis, paralysis of the palate, mania, cholera, and dysentery. Overall, five percent of the city were destroyed, and the population and economic development were severely damaged. This study aims to evaluate the importance of the history of local medicine in Tehran, the spread of Spanish flu, World War I, and presence of Russian, Ottoman, and British troops in Iran during the flu outbreak. The critical role of Britain in artificial famine, malnutrition, and drug embargo was assessed, as well.