<P> In August 1918, a more virulent strain appeared simultaneously in Brest, France; in Freetown, Sierra Leone; and in the U.S. in Boston, Massachusetts . The Spanish flu also spread through Ireland, carried there by returning Irish soldiers . The Allies of World War I came to call it the Spanish flu, primarily because the pandemic received greater press attention after it moved from France to Spain in November 1918 . Spain was not involved in the war and had not imposed wartime censorship . </P> <P> The global mortality rate from the 1918 / 1919 pandemic is not known, but an estimated 10% to 20% of those who were infected died . With about a third of the world population infected, this case - fatality ratio means 3% to 6% of the entire global population died . Influenza may have killed as many as 25 million people in its first 25 weeks . Older estimates say it killed 40--50 million people, while current estimates say 50--100 million people worldwide were killed . </P> <P> This pandemic has been described as "the greatest medical holocaust in history" and may have killed more people than the Black Death . It is said that this flu killed more people in 24 weeks than AIDS killed in 24 years, and more in a year than the Black Death killed in a century . However, a 2016 article in The Atlantic states that the Black Death, over the course of the decade of the 1340s, killed more than 10% of the world population whereas the 1918 flu pandemic killed less than half this percentage . </P> <P> The disease killed in every corner of the globe . As many as 17 million died in India, about 5% of the population . The death toll in India's British - ruled districts alone was 13.88 million . </P>

Where did the outbreak of the 1918 influenza viral strain originate