The 1918 influenza pandemic (colloquially known as the Spanish flu) was an unusually deadly influenza pandemic, the first of the two pandemics involving H1N1 influenza virus,  It infected 500 million people around the world, or about 27% of the world population which was then 1.8 and 1.9 billion, The death toll is estimated to have been anywhere from 17 million to 50 million, and possibly as high as 100 million, making it one of the deadliest epidemics in human history.                     

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The World Health Organization (WHO) declared COVID-19 a global pandemic on Wednesday 11 March, 2019 as the new coronavirus, which was unknown tjust three months ago, has rapidly spread to more than 121,000 people from Asia to the Middle East, Europe and United States.