AUDIE CORNISH, HOST:
The coronavirus variant first spotted in India appears to be spreading in the United States, and that's worrisome because this variant appears to be highly contagious and better at evading the immune system. NPR health correspondent Rob Stein is here to talk more about it. Welcome back, Rob.
ROB STEIN, BYLINE: Thanks. Nice to be here.
CORNISH: Remind us exactly which variant this is.
STEIN: Yeah, so the one we're talking about is called B1617. And like you said, it was first spotted in India, and it's sometimes called the double mutant because it's got two mutations that scientists have been concerned about because they may make the virus more of a threat. And we've all seen how bad things are right now in India. You know, it's unclear how much of that is because of this variant. But this variant may be playing a role.
CORNISH: As you said, B1617 - it's already in the U.S.
CORNISH: How common is it?
STEIN: So, you know, the variant that was first spotted in the U.K. is still the dominant strain in the United States. But the one first spotted in India seems to be on the rise and could already be starting to overtake some of the other variants that have been circulating in the country. According to the latest CDC estimate, this B1617 variant may have increased from about 1% of infections to more than 3% nationally. And it may be way more common than that in some parts of the country. The CDC estimates it could account for more than 10% of infections in the New York, New Jersey area and more than 17% of infections in some Western states - you know, like Colorado, Montana, Utah, Wyoming and the Dakotas. I talked about this with Dr. Jeremy Luban at the University of Massachusetts Medical School.
JEREMY LUBAN: It looks like the 617 is gaining ground. It's outcompeting the other viruses. It's replacing whatever variants were there before. And it's always a concern when something like this changes because we don't know what will happen.
CORNISH: Rob, can you outline what paths this could take?
STEIN: Yeah. So, you know, this variant looks like it could be the most contagious one yet to come along. So, you know, it could just ratchet up the pandemic again in this country if it starts spreading, you know, widely. Now, the good news is that the vaccines look like they probably work really well against it, especially at protecting people from getting really sick and dying, which is the most important thing, but maybe just not quite as well at preventing any infections at all. But the immunity the vaccines do provide may not last as long, so we may need boosters sooner. And people may also not be as protected from infection if they had already been infected with one of the earlier strains, so they may be more vulnerable to this one.
I talked about this with Dr. David Montefiori at Duke University. He's been studying how good this variant is at outsmarting the immune system.
DAVID MONTEFIORI: I'm very concerned about the increasing number of cases of this variant in the United States and other parts of the world. You know, we're keeping a close eye on it. What it's likely to do is prolong the pandemic, and we want to get this pandemic under control just as quickly as possible.
STEIN: So, you know, Audie, it's just another reason why it's really important to vaccinate as many people as possible as quickly as possible, both in this country and around the world, to keep this variant from taking off and prevent new ones from evolving.
CORNISH: That's NPR health correspondent Rob Stein.
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