Hi and welcome to COVID Quickly, a scientific American podcast series.

This is your fast track update on the COVID pandemic.

We bring you up to speed on the science behind most urgent questions about the virus and

the disease.

We demystify the research and help you understand what it really means.

I'm Josh Fishman, scientific American senior health editor.

Tanya Lewis, usually here with me, has the day off.

Today, new research shows how old cold viruses may help protect you against the coronavirus

causing the pandemic.

And vaccine makers are not rushing out shots against the Omicron variant, even though

the original shots have lost some effectiveness.

What's the hold up?

We'll explain.

From early in the pandemic, it's been clear that not everyone is equally vulnerable to

SARS-CoV-2, the coronavirus that causes COVID.

Some people get really sick while others have mild symptoms or none at all.

And this was true before any of us were protected by vaccines.

Overall, about 80% of infected people get a mild illness.

The virus is so wildly infectious, though, that the 20% of serious cases have been a global

catastrophe, 5.5 million people dead, 850,000 of them in the US.

But in people who don't get very ill, what's protecting them?

We hear a lot about neutralizing antibodies, but this is a new virus to us.

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