The Doomsday Flu

In 1918 an innocuous seasonal disease mutated into a monster, dubbed the Spanish Flu. Within three months it had killed 22 million people across the globe - more than ten times the death toll of the medieval Bubonic Plague. It outstripped the slaughter of World War I, bringing that war to a halt. Where did the flu come from and why did it suddenly disappear?

This is the story of the flu that brought the world to a standstill in 1918. It killed within hours of striking, spreading rapidly across the world from America where it began. Transatlantic ocean liners would arrive with 7 per cent fewer passengers than when they set sail.

The flu's contagion was inexplicable - it killed strong healthy farmhands and spared stunted city-dwellers. Trying to understand the disease, Americans used volunteers from its punishment stockades as guinea pigs, injecting them with matter from infected lungs. The volunteers remained healthy, but the doctors conducting the experiments died.

Scientists estimated that if the disease maintained its rate of acceleration it would eradicate mankind in a matter of months. But the disease disappeared as suddenly as it arrived. Recent research suggests that the disease came to us via pigs and that it could happen again at any time.