The Delta Variant And The Latest Coronavirus Surge : Short Wave COVID-19 cases are on the rise in the last month due to the Delta variant. NPR correspondent Allison Aubrey talks with Emily Kwong about where the virus is resurging, how some public health officials are reacting and what they are recommending. Also, with a spate of outbreaks at summer camp, officials are weighing in on what parents can do before they send children to camp.

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The Delta Variant And The Latest Coronavirus Surge

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MADDIE SOFIA, BYLINE: You're listening to SHORT WAVE from NPR.


KWONG: All right. Emily Kwong here with science and health correspondent Allison Aubrey, who's been joining us for updates on the latest coronavirus news. What's up, Allison?

ALLISON AUBREY, BYLINE: Hey, Emily. Great to be here.

KWONG: Hey. So on a lot of people's minds these days is the delta variant. It's quickly becoming the dominant coronavirus variant in multiple countries. And Allison, I want to know, how is it affecting the U.S.?

AUBREY: Yeah. Well, after steep declines, coronavirus cases are on the rise again, thanks to this fast-spreading variant. The number of new cases has tripled since June. Hospitalizations and deaths are rising, too. This is mostly among unvaccinated people. And overall, these increases are concentrated in places with low vaccination rates.

KWONG: So today on the show, what you need to know about this fast-spreading variant and what precautions we may need to be taking.

AUBREY: You're listening to SHORT WAVE, the daily science podcast from NPR.


KWONG: OK, Allison, you were just saying daily cases and hospitalizations are dramatically rising here in the U.S. Where is this happening, and why?

AUBREY: Well, the U.S. is averaging about 30,000 new cases a day. And just for some perspective, this is far fewer than the 200,000 or so cases a day back in the winter. But there's been a 70% increase, on average, over one week. There are significant increases in states with low vaccination rates, including Arkansas, Mississippi and Missouri.

KWONG: Right. And Allison, Surgeon General Vivek Murthy warned that this rise in hospitalizations and deaths that are largely preventable may only continue.


VIVEK MURTHY: I am worried about what is to come because we are seeing increasing cases among the unvaccinated in particular. And while, if you are vaccinated, you are very well protected against hospitalization and death, unfortunately, that is not true if you are not vaccinated.

AUBREY: In fact, CDC officials say 97% of people hospitalized now with COVID are unvaccinated. Of course, there are instances where fully vaccinated people are getting infected, so-called breakthrough cases, but they tend to get much less sick. CDC Director Rochelle Walensky says we now have a pandemic of the unvaccinated.

KWONG: Pandemic of the unvaccinated, yeah. So the delta variant, especially among those without the vaccine, this is what's causing this surge in cases.

AUBREY: Yeah. I mean, the delta variant is estimated to be about 225% more transmissible than the original coronavirus strain. So, you know, when this variant finds pockets of unvaccinated people, it can just spread so much more quickly. Former FDA Commissioner Scott Gottlieb spoke on CBS about what this means in the coming weeks and months.


SCOTT GOTTLIEB: This variant is so contagious that it's going to infect the majority of them. Most people will either get vaccinated or have been previously infected, or they will get this delta variant. And for most people who get this delta variant, it's going to be the most serious virus that they get in their lifetime in terms of the risk of putting them in the hospital.

AUBREY: You know, the variant just can't be underestimated, he says. And that's why we are hearing, yet again, more pleas from public health officials to the roughly 30% of adults out there who have not yet been vaccinated in the U.S. to go ahead and get the shots.

KWONG: Right. I mean, this is super worrying. And so many people remain hesitant. But simultaneously, of course, millions of people who were eager to get vaccinated at the first opportunity back in the winter or are vaccinated now, are now wondering, what about a booster?

AUBREY: Well, there's really no decision yet on boosters. But at a White House briefing last Friday, adviser Jeff Zients said that the administration is ready for the possibility of boosters if and when the science shows they're needed. Dr. Anthony Fauci has said that the CDC and the FDA are getting as much data as they possibly can, including tracking the levels of immunity in people who were in the vaccine clinical trials to see if their immunity is waning.

KWONG: OK. And I heard there's a study underway to test a kind of mix-and-match approach to these boosters, right?

AUBREY: That's right. I mean, they're giving a shot of the Moderna vaccine as a booster to people who originally got any of the three authorized vaccines, including the Johnson & Johnson vaccine and the Pfizer vaccine. I spoke to Robert Atmar about this. He's a professor of infectious diseases at Baylor College of Medicine, and he's also a co-principal investigator of the study.

ROBERT ATMAR: What we want to figure out is, what kind of reactions do people have when they get a booster dose, and do they generate a good immune response both to the original coronavirus strain but also to the variants of concern?

AUBREY: You know, although there's not a strategy yet or a decision about whether a booster is needed, the CDC is doing a lot of thinking about this. And it could be that boosters will be recommended for some portion of the U.S. population, such as older adults above a certain age, or people who are immunocompromised.

KWONG: OK. So in the meantime, as the delta variant continues to surge, is there any move to reinstate masking mandates or other protections?

AUBREY: Well, over the weekend, Los Angeles County reinstated a mask mandate for both unvaccinated and vaccinated people. And Surgeon General Murthy said local leaders certainly have the flexibility to do this, though it's really very unlikely that there will be any kind of new national mask mandate. But that doesn't mean it's not a good idea to mask up. I mean, lots of public health experts tell me it makes good sense to stay masked right now in crowded indoor settings because this variant is so transmissible, and it's still possible for fully vaccinated people to become infected. I spoke to one doctor, Sage Myers. She's an emergency room physician at Children's Hospital of Philadelphia. And she points out that masking can also help protect children and other people who are vulnerable in your household.

SAGE MYERS: We're expecting our unvaccinated children to continue to wear those - wear their masks. And helping them to feel more comfortable takes us doing it, too. And so I definitely will wear my mask when I'm with my 11-year-old who can't be vaccinated yet, who has to have her mask on, even if it's a situation that, as a vaccinated person, I may otherwise have been able to not wear it.

KWONG: Yeah. I mean, I have no plans to stop carrying my mask around. You know? Just so I can put it on when I need to.

AUBREY: Yeah. It's not that big of a deal. And, you know, we know it can be effective in helping protect us and others.

KWONG: Yeah, yeah. So, Allison, some experts have called on the CDC to change its guidance, actually, to encourage more masking. Right?

AUBREY: That's right. Leana Wen, a physician and former health commissioner for the city of Baltimore, and Ali Mokdad, a well-known modeler at the Institute for Health Metrics and Evaluation - they've both been pretty critical of the CDC. Wen tweeted that 38 states have a greater than 50% increase in COVID infections. And she argues that this can be traced back to the CDC's actions that she says basically ended mask mandates. She says the honor system did not work and instead disincentivized people from getting vaccinated.

KWONG: Yeah, right - 'cause there were no repercussions for unvaccinated people going unmasked.

AUBREY: That's right. And experts say it would make it a lot easier for local leaders to reinstate mask mandates if the CDC were signaling that it's beneficial.

KWONG: Yeah. One other thing I've been thinking about before we go, Allison - it's summer camp season, summer break. And there have been a spate of outbreaks tied to camps. So if you're a parent, what's the best advice to keep kids safe?

AUBREY: Yeah. There are reports of camp outbreaks in a bunch of states - Texas, Illinois, Florida, Missouri, Kansas. And Dr. Sage Myers, who's also a medical director at a camp, says the risks can be higher at sleepaway camps compared to day camps because kids are bunking together. They're just in close quarters more. So more precautions may be needed.

MYERS: We are testing prior to arrival, encouraging families to quarantine their children for the days prior to going to camp, definitely between five and seven days of quarantine and keeping them away from other contact with other people. And so camps really need to be on top of that. And even minor symptoms, kids have to quarantine and be tested to ensure that they aren't the start of a spread.

AUBREY: This is especially true for the under-12 crowd that cannot be vaccinated yet.

KWONG: Yeah. We all need to be staying safe while having fun this summer. That is my takeaway from this reporting. Allison, thank you so much for joining us and giving us these updates.

AUBREY: Great to be here.


AUBREY: This episode was edited by Jane Greenhalgh and Gisele Grayson, produced by Rebecca Ramirez.

KWONG: It was fact-checked by Indi Khera. I'm Emily Kwong.

AUBREY: I'm Allison Aubrey.

KWONG: Thank you for listening to SHORT WAVE, the daily science podcast from NPR.


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