The Spanish Flu
The\xa0Spanish flu, also known as the\xa01918 flu pandemic, was an unusually deadly\xa0influenza pandemic. Lasting from January 1918 to December 1920, it infected 500\xa0million people\xa0\u2013 about a quarter of the world's population at the time. The death toll is estimated to have been anywhere from 17\xa0million to 50\xa0million, and possibly as high as 100\xa0million, making it one of the\xa0deadliest pandemics\xa0in human history.[2]