The richest man on the planet, Bill Gates, says he's not nearly so fearful nuclear war will wipe out humanity — a pandemic has a shockingly far greater deadly potential.
"I rate the chance of a nuclear war within my lifetime as being fairly low,"
Gates says in an interview with Vox.
"I rate the chance of a widespread epidemic, far worse than Ebola, in my lifetime, as well over 50 percent."
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Gates tells Vox a model he funded to help with his Bill and Melinda Gates Foundation's work eradicating polio was used to look into how a disease like the Spanish flu of 1918 would work in today's world.
"Look at the death chart of the 20th century," he tells Vox. "I think everybody would say there must be a spike for World War I. Sure enough, there it is, like 25 million. And there must be a big spike for World War II, and there it is, it's like 65 million.
"But then you'll see this other spike that is as large as World War II right after World War I, and most people, would say, 'What was that?'"
"Well, that was the Spanish flu."
The Spanish flu killed between 20 million and 40 million people worldwide.
Gates tells Vox no one knows where the Spanish flu came from — it was just called the "Spanish flu" because the press in Spain were the first to report on it.
In today's world, a Spanish flu-like outbreak "within 60 days [is] basically in all urban centers around the entire globe," Gates says. "That didn't happen with the Spanish flu."
And in 250 days, it would kill more than 33 million people.
"We've created, in terms of spread, the most dangerous environment that we've ever had in the history of mankind," Gates says.
The reason the disease could spread so fast is that human beings now move around so fast, and Gates' model, figured about 50 times more people cross borders today than did so in 1918.
Vox notes a 1990 study on infectious disease found they "have likely claimed more lives than all wars, noninfectious diseases, and natural disasters put together."
Flu kills 10,000 in a "good year," and "in a bad year … kills over five times that," Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, tells Vox.
Last year, the Ebola outbreak killed more than 10,000 people — and showed how unprepared the world was for a well-known disease that spreads slowly.
"Where was the equivalent of the military reserve, where you get on the phone and you said to people, Now come! And they had been trained, and they understood how to work together," Gates tells Vox.
"People who want to volunteer, do we pay them? What do we do with them after they come back, when people might have this fear that they've been exposed? Are employers going to take them back? What are the quarantine rules? It was completely ad hoc."