I'm Brian Lehrer. This is my daily politics podcast from WNYC Studios. It's Tuesday, December 28th.

Let's keep getting to know our new neighbor, our new roommate, the Omicron variant, similar to, but different from its

relatives like Beta, Delta, and what virologists call the ancestral variant, which dates

back to ancient times, meaning early last year. And with so many people getting sick and so

many people not feeling sick, but testing positive anyway. Let's requaint ourselves

with what it means to isolate and to quarantine. The big news from yesterday afternoon, you've

probably heard it, is that the CDC has shortened the length of time that certain people

with COVID have to stay away from others. Our very special guest for this is Dr. Daniel Griffin, infectious disease clinician

and researcher at Columbia, chief of infectious disease at Pro Health, Senior Fellow for Infectious

Disease at UHG Research and Development, president of the group Parasites Without Borders,

and as some of you know, the weekly presenter of the

COVID clinical update on the podcast this week in virology. Dr. Griffin, thanks for coming back on

with us at a really astonishing and frightening time in the pandemic, just when we thought we had

maybe turned the corner a few months ago. Welcome back to WNYC. Oh, thank you, Brian.

Can you explain first what the CDC did yesterday because I think a lot of people are confused.

What exactly got shortened from 10 days to five days? Yeah, I think that you are right.

A lot of people are confused, shocked, not sure how they feel about this.

And thank you for mentioning this week in Virology clinical update because I tried to get people a little bit ready for this because the science was moving in this direction.

But let's talk about what exactly they did. And there's a little bit of terminology here. So there'll be a test, not at the end,

but basically every day of our lives going forward. Isolation of the infected. So when we talk about

isolation, we're talking about what an infected person should do to keep those around them safe. And it had

been previously a 10-day period of isolation if you were infected. And what they

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