STEVE INSKEEP, HOST:
Just as the omicron surge starts to recede in parts of this country, scientists are watching another version of omicron. It's spreading in Asia and parts of Europe. This week, it was even detected in several U.S. states, including California, Washington and Texas. So we've brought in NPR global health correspondent Michaeleen Doucleff. Michaeleen, good morning.
MICHAELEEN DOUCLEFF, BYLINE: Good morning, Steve.
INSKEEP: This sounds a bit dismaying. What's going on?
DOUCLEFF: Yeah, you know, you're not the only one to feel this way. Many scientists I speak to are like, you know, when is this going to stop or at least slow down?
DOUCLEFF: But I'm here with some good news. And that's while this new version of the virus does have scientists on alert, it isn't a new variant of concern. It's actually a different version of omicron, kind of like a sibling. I was talking to Emma Hodcroft about this. She's an epidemiologist at the University of Bern and one of the key scientists tracking variants around the world. She says when researchers first discovered omicron, they also found the second version right around the same time.
EMMA HODCROFT: They share a lot of mutations. So they're, like, obviously related, but they're also different - very sibling-like, in my opinion, like, exactly how you feel about siblings, right? Definitely related but also different.
DOUCLEFF: At first, scientists kind of thought the second version was weaker, kind of like a little sister that couldn't keep up with the first version, which was spreading really fast all over the world. So they thought this little sister was just going to die or peter out.
INSKEEP: I have a lot of experience with little sisters. They don't peter out. They get bigger, which seems to have happened here. So how did that happen?
DOUCLEFF: Yeah. So over the past several weeks, this new omicron did something really surprising in Denmark, and it could possibly happen in the U.K. and Germany. What happened is that as cases of the original omicron started to decline and the surge started to slow down in Denmark, this new version, this little sister, started spreading really rapidly and took over and now is making Denmark's current surge last longer.
INSKEEP: OK. Is that going to happen here, then?
DOUCLEFF: Yeah, you know, we don't know yet, but that is obviously the concern. You know, evidence suggests this second omicron, this little sister, is just as contagious as the first one and possibly a bit more. So it will spread here, though it's rare right now.
INSKEEP: Is this version of omicron less deadly than others in the same way that the version of omicron we've been familiar with has been less deadly than others?
DOUCLEFF: Yeah. So so far, data from Denmark suggests that that's the case. You know, this new version doesn't appear to be more dangerous than the first omicron, which is great news. The disease it causes and the severity of that disease look very similar to what we see right now with this original version. And furthermore - and this is really important - the two versions of omicron share a bunch of mutations, and because of that, doctors and scientists expect that the vaccine and the booster shots are going to work about the same with this little sister. I was talking to Dr. Peter Chin-Hong about this. He's an infectious disease specialist at the University of California, San Francisco. He says for healthy people, if you're boosted, you're going to be well protected from severe disease. And that's also likely true if you were infected recently with the original omicron.
PETER CHIN-HONG: I have no guarantee that you wouldn't get reinfected, meaning that you might have a sniffles or might feel like you got another cold. But I feel very, very confident that you would be protected from serious disease in the general population.
DOUCLEFF: And, you know, Steve, that is really the key thing going forward with this pandemic, you know, is keeping people from getting sick enough that they end up in the hospital or even dying. Chin says going forward, this is what we really need to focus on.
INSKEEP: NPR's Michaeleen Doucleff, thanks so much.
DOUCLEFF: Thank you, Steve.
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