As a citizen, probably one of the best ways I can contribute to combat

in the virus is being a participant in a trial like this.

If there's anything on the planet that everybody is hoping for, it's a vaccine for COVID-19.

And all over the world, trials are underway.

The timeline for the development has been compressed dramatically,

with testing on animals and humans taking place at the same time.

Usually, animal testing comes at least a year before a vaccine would ever get to humans.

But with the help of existing research on previous coronaviruses, like mirrors and SARS,

the search for a COVID vaccine has become one of the fastest moving in history.

I'll explain the promise and the pitfalls during this race to get a vaccine.

I'm Dr. Sanjay Gupta, CNN's Chief Medical Correspondent.

And this is coronavirus, fact versus fiction.

You can have nausea, you can sometimes develop fever,

which may not be a bad response necessarily, because it might indicate the immune system is mounting response,

meaning it could fight the virus in the future potentially.

But you really never know what's going to happen.

That's 31-year-old John Doyle.

He's one of a small handful of people in the United States testing a possible vaccine for COVID-19.

When I spoke with Sean, he said his family and friends were nervous about his involvement with experimental medicine.

But ultimately, they trusted his instincts as a medical student.

And he's also had some practice.

Sean was involved in a 2017 trial for an Ebola vaccine.

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