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 the most urgent questions about the virus

and the disease.

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

I'm Tony Lewis.

I'm Josh Fishman.

And we're scientific American senior health editors.

Today we're going to discuss the new alphabet soup of variants and sub variants likely

to be around this winter.

And we'll talk about ways that boosters add protection, even if you've already had

COVID.

We're heading into another pandemic winter.

Although no completely new variant of the COVID virus has emerged yet, there are several

new Omicron sub variants.

And you call them Halloween scarions, Tanya.

What do we know about them so far?

That's right.

Well, the Omicron variant first appeared last fall.

And for the last year, COVID cases have mostly been driven by different versions of Omicron.

First there was B1.1.529, then there was BA1, BA2 and BA3, then BA4 and BA5.

Now there are some new kids on the block.

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