Microsoft founder Bill Gates is out to save the world. And he knows it’s not going to be easy.

Vox’s Ezra Klein recently asked Gates what keeps him up at night, what his “nightmare scenario” is for the human race.

Fellow tech icon Elon Musk worries about artificial intelligence, the possibility that robots are going to rise up and enslave us. Gates does too. But he considers such concerns “very low probability.” He’s even surprisingly sanguine about the threat of nuclear war.

But a global pandemic? That possibility strikes him as very real. “I rate the chance of a widespread epidemic far worse than Ebola, in my lifetime, as well over 50 percent,” he told Klein.

The 2014-16 Ebola epidemic in West Africa was the largest in history and killed thousands of people, according to the Centers for Disease Control and Prevention.

Gates, through his philanthropic foundation, has focused a lot of time and money on this issue in recent years. He funded a “disease modeling group” to study the problem of controlling an epidemic in the modern age.

“The Ebola epidemic showed me we’re not ready for a serious epidemic,” he said.

Gates points to the Spanish flu pandemic of 1918 that killed tens of millions of people across the world. A similar outbreak today, he says, would be far deadlier because of the world’s interconnected travel systems.

“Within days it’s basically in all urban centers of the entire globe,” he said, referring to the results of his team’s pandemic modeling. “That is very eye-opening. That didn’t happen with Spanish flu in the past.” He added: “This is the most likely thing by far to kill over 10 million excess people in a year.”

Watch Gates talk about the pandemic problem and the possible solutions:

— Douglas Perry

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