AILSA CHANG, HOST:
Dr. Anthony Fauci is calling the Delta variant the greatest threat to the nation's prospects for winning the battle against the COVID-19 pandemic. NPR health correspondent Rob Stein joins us now with more details.
Hi, Rob.
ROB STEIN, BYLINE: Hey, Ailsa.
CHANG: Hey. So this Delta variant, I mean, it's the strain that was first spotted in India - right? - before it took over in the United Kingdom and other countries. Why is Dr. Fauci issuing such a strong warning about it now in the U.S.?
STEIN: You know, Ailsa, it's a combination of factors. No. 1 is it's incredibly contagious, the most contagious mutant to emerge yet. And it's spreading fast in this country, so fast now that it's doubling the proportion of infections it's causing every two weeks and already accounts for more than 20% of all new infections. Let's listen to a little bit of what Dr. Fauci said about this today at the White House COVID-19 briefing.
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ANTHONY FAUCI: Similar to the situation in the U.K., the Delta variant is currently the greatest threat in the U.S. to our attempt to eliminate COVID-19.
STEIN: You know, according to some estimates, the Delta is on such a fast trajectory that it's likely to become the dominant strain in the U.S. within weeks. In fact, CDC Director Rochelle Walensky noted at the same briefing that the Delta already accounts for nearly half of all infections in some parts of the country, you know, like parts of the Midwest and West.
CHANG: Wow. OK, so it spreads really quickly. But does it make people sicker?
STEIN: You know, it looks like that could be the case. Dr. Fauci cited some new research that indicates people are significantly more likely to end up in the hospital if they catch this virus compared to if they caught the original strain. And he noted that young adults and children look like they're driving the spread of the virus, at least in Britain that is.
CHANG: OK. Well, the question on everyone's minds is, how well do our current vaccines work against the Delta variant?
STEIN: Yeah. We're all wondering, am I protected or not? And that's the good news. All the evidence so far indicates that they work very well if people are fully vaccinated. But, you know, remember; there are lots of unvaccinated people still in this country. So Dr. Fauci says this new threat posed by the Delta variant makes it more urgent than ever that people roll up their sleeves, especially, you know, given how close the country is to finally getting back to normal.
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FAUCI: We have the tools, so let's use them and crush the outbreak.
STEIN: The fear, Ailsa, is that the Delta variant could spark yet another round of new outbreaks in the parts of the country where lots of people still aren't vaccinated. In fact, a new projection that just came out found that yet another national surge could start as soon as July if a virus as contagious as the Delta sweeps through unvaccinated parts of the country.
CHANG: Well, if the Delta variant does spread through certain parts of the U.S. unchecked, could it lead to the emergence of even more dangerous variants?
STEIN: You know, absolutely. As we've been saying for a while now, the more the virus spreads, the greater the chances that even more dangerous mutants could evolve. If we let it run wild, who knows what could emerge? And, you know, Dr. Walensky noted that there's no reason for one more person to get sick or die from the pandemic in this country at this point when the vaccines have essentially made COVID-19 a preventable disease.
CHANG: That is NPR's Rob Stein.
Thank you, Rob.
STEIN: You bet, Ailsa. Transcript provided by NPR, Copyright NPR.