This week in virology, the podcast about viruses, the kind that make you sick.

From micro TV, this is Twiv, this week in virology, a special episode recorded on August 7, 2023.

I'm Vincent Racken-Ello. You're listening to the podcast, all about viruses.

Joining me today from the state of Maryland, Coistia Tumakoff. Welcome back.

Thank you. Thank you, Vincent.

And from Germany, Roelandina, welcome back, Roel.

Hey, Vincent, thank you.

Both of you have been on this program a couple of times in various places. We're scattered

all over the world today. But the goal today is to talk about NPV2. The end stands for novel,

is that right? Right. It's a derivative of Albert Sabin's OPV serotype 2, which I a few months

ago on Twiv called the failure and both Raul and Coistia emailed me and said, no, it's not a failure.

It's not fair. So I said, come on and talk about it. So here we are. We're going to talk about it.

And give it a broad discussion. So first, let's talk about why was NPV2 designed to begin with?

What was the problem with Sabin's original OPV2 that necessitated a redesign? Maybe

Coistia, you could start by talking about that. Sure. Yes. I mean, when Sabin's strains were introduced

at the turn of the 1950s, 1960s, I mean, at the time, there was not much attention paid to

the side effects that this vaccine can produce. And only by the, I would say, mid-1980s,

it became clear that these strains are not really as stable as we hoped for. Even though reports

were trickling in earlier, but then by the time when the United States and Europe practically

eliminated polio, there was a realization that the only few cases of periodic polio that

are observed, actually are caused by a vaccine derived virus. At the time, it was called

vaccine-associated pervetic polio. It was a virus. Sabin virus that accumulated a few mutations.

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