ARI SHAPIRO, HOST:
The coronavirus variant that was first detected in India has become a, quote, "variant of concern" in the United States. That's according to the Centers for Disease Control and Prevention. The announcement comes as the dangerous new variant, the Delta, has been spreading more widely in this country. NPR health correspondent Rob Stein is with us to talk about this. Hi, Rob.
ROB STEIN, BYLINE: Hey, Ari.
SHAPIRO: There are so many new variants that have emerged. What makes this one unique?
STEIN: Yeah. So, you know, as you said, this is the variant that was first spotted in India. And you might remember some people originally called it the double mutant because it had two mutations that had made earlier variants more of a threat. It's now known as the Delta variant. And it turned out to be the most contagious variant to come along yet. It spreads fast, like 50% faster than the one first spotted in the U.K. And that one was way more contagious than the original virus. And that helps explain why it just ravaged India and then took over in Britain, forcing the U.K. to roll back some plans to reopen. It's also causing big problems in lots of other parts of the world. And now the CDC says enough data has accumulated about the variant in this country to declare it a real threat here, too.
SHAPIRO: Tell us more about what that data is. What does it show?
STEIN: Yeah, so it really looks like it's taking off and starting to overtake some of the other variants that have become dominant in this country. The CDC estimates that it went from less than 3% of all infections to more than 6% and now may account for almost 10% of all infections. I talked about this with Summer Galloway at the CDC.
SUMMER GALLOWAY: It was really when we saw this data and we could see how quickly this was increasing in the United States and the data from the U.K. indicating that it's more transmissible - that's a very concerning feature, that it's spreading, you know, more easily from person to person. That's definitely concerning.
STEIN: And it looks like the Delta variant is even more common in some parts of the country. The CDC estimates it already accounts for almost 13% of infections in some Southern states, like Texas and Louisiana, more than 17% percent of infections in some Northeastern states, like New York and New Jersey, and more than 25% of infections in some Western states, like Utah, Montana, Colorado.
SHAPIRO: So it's more transmissible. It's spreading fast in the U.S. Does it make people sicker than other variants?
STEIN: Yeah. Yeah, so the evidence is mounting that it could. A study just came out earlier this week from Scotland, indicating that people who catch the Delta variant may be twice as likely to end up in the hospital. So it just adds to the worry that this is a, you know, really nasty mutant.
SHAPIRO: How do the vaccines do against this variant?
STEIN: You know, that's - Ari, that's the good news. All the evidence so far indicates that the vaccines still work really well against this variant - maybe not quite as well as they did against the original strain, but still quite well if people get fully vaccinated. So the thinking is this variant probably won't cause a big new national surge this summer in this country, but it could cause big outbreaks in the parts of the country where lots of people still haven't gotten vaccinated. I talked about this with Angela Rasmussen. She's a virologist at the University of Saskatchewan.
ANGELA RASMUSSEN: If you have been fully vaccinated, then this variant isn't really much of a concern. However, if you are not fully vaccinated or if you're unvaccinated, it's a big concern. So the real moral of the story is to not worry about this variant; you really should go out and make sure you are fully vaccinated.
STEIN: And, you know, Ari, there are parts of the country where only about a third of people are fully vaccinated, especially in some Southern and Western states where the Delta variant is spreading fast.
SHAPIRO: That's NPR's Rob Stein. Thank you very much.
STEIN: You bet, Ari.
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