Around the world, there are more than 90 vaccines in development against SARS-CoV-2, the virus that causes COVID-19, but there there are still some huge challenges to overcome in the race to create a vaccine.

But what does a vaccine look like? Who is getting close and why does it matter? What does it take to bring a vaccine to market? And what are the politics of distributing a life-saving vaccine during a global emergency?

And the big question: What if we don't manage to develop one and just how much will it cost us if we fail? Hint: the answer is in trillions.

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