Dr. Jerome Adams, who served under President Trump, once advised against mask wearing. Now, cases are rising, fueled by the delta variant, and Adams says even the vaccinated may need to mask up.

Transcript

A MARTINEZ, HOST:

The delta variant is pushing coronavirus numbers up in the U.S. The number of people getting COVID is nearly three times greater than it was just a month ago. And CDC director, Dr. Rochelle Walensky, says it's due in large part to those who are still unvaccinated.

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ROCHELLE WALENSKY: We are seeing outbreaks of cases in parts of the country that have low vaccination coverage because unvaccinated people are at risk.

MARTINEZ: All right. So is it time to change the guidance on masking requirements again? Former U.S. Surgeon General Dr. Jerome Adams says, the CDC may need to.

Dr. Adams, welcome to the show. I know the CDC's masking guidance relied on a - kind of an honor system. Wear a mask indoors if you're not vaccinated. Now, on Twitter, you call that guidance harmful. Why'd you tweet that?

JEROME ADAMS: Well, though well-intentioned, the former CDC guidance or, more appropriately, the messaging of it has just absolutely, unequivocally failed. Cases are rising everywhere. More people than ever, vaccinated and unvaccinated, are going maskless. And it doesn't seem to have convinced anyone to get vaccinated. And now you have local law enforcement officials, like the LA County Sheriff, directly citing the CDC guidance as a reason not to enforce local health mandates.

But what your listeners need to understand is this delta strain is much more contagious - 1,000 times more virus particles in the air if you have it. So even if you're an asymptomatic young person, maybe you're an Olympian or a boxer or a college baseball player or an NBA star, you're now 1,000 times the problem to everyone around you by being unvaccinated, even if you get it and you're asymptomatic.

MARTINEZ: Doctor, what's the difference between the guidance and the messaging?

ADAMS: Well, the guidance was based on vax it or mask it. And the science at the time suggested that if you were vaccinated, you had a very low chance of spreading the virus. So you could go without a mask. The problem is that what people heard was, no more mask. And they also rolled it out so quickly that it kind of took local health officials, many that I've talked to, completely by surprise. They didn't have time to implement a plan. Businesses - Walmart just throws their hands up in the air and says, hey, we don't have a way to figure out who's vaccinated or who's not - so no mask for anybody. That was the problem with it.

MARTINEZ: So does the guidance need to change from the CDC?

ADAMS: The - I absolutely think that the CDC needs to come out and and say to people, look, this virus is changing rapidly because here's something else that people don't understand. When you look at the Israeli data, the Pfizer vaccine was still incredibly effective at preventing severe disease and hospitalization but 64% effective at stopping spread. So even the vaccinated now could be spreading - much less spread relative to being unvaccinated. But that's being counteracted by delta being so much more contagious. We cannot afford to send the message that if you're vaccinated, you have no worries and no responsibilities.

We need both vaccinated and unvaccinated adults to take this seriously. And taking it seriously means if your local health officials say cases are going up and positivity rates are going up in your location, you may need to vax it and mask it.

MARTINEZ: Now, one place where cases and hospitalizations are rising is Arkansas. Republican Gov. Asa Hutchinson spoke to All Things Considered yesterday. Let's take a listen.

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ASA HUTCHINSON: Quite frankly, this delta variant, the longer it hangs around, the easier it is to give positive results to somebody who has been vaccinated.

MARTINEZ: Dr. Adams, how likely is it that vaccinated people will be able to catch COVID and show symptoms?

ADAMS: Well, we still don't know that yet. And that's one of the challenges. You know, I talked about the messaging that Tony Fauci and I had on masking last year. And one of the things is, this virus has humbled us. What we thought we knew changes very quickly.

We thought there was low asymptomatic spread. We, quite frankly, were not suspicious enough of reports that there were high degrees of asymptomatic spread. And our messaging didn't reflect what ultimately came to be true. This delta variant is changing what we thought we knew. And again, when you look at boosters, particularly for people who are vulnerable or older, it may be that at least in terms of stopping spread, that we need to, again, focus on vaccinated as well as unvaccinated. Now, I don't want people to take that vaccines are not highly effective.

MARTINEZ: Sure.

ADAMS: They're still highly effective at preventing serious disease and death. And you're going to spread less if you're vaccinated than if unvaccinated. But again, we may need to vax it and mask it...

MARTINEZ: Yeah.

ADAMS: ...Sorry - in places where cases are going up. And you've got places where you've got 10%, 15%, 20% positivity rates.

MARTINEZ: Dr. Adams, I realize we don't know what we don't know. But that's frustrating and a little scary to know that you and Dr. Fauci didn't know as much or (laughter) more than us. I mean, it feels like - we're looking to you to tell us what to do and lead us.

ADAMS: Well, exactly. And one of the things that we need to have comfort in is letting the public understand that we are trying to build the plane as we're flying it, that this virus is changing in real time. And that's how the scientific process works. Science isn't a destination. It's a journey.

And we need to have the courage to say, look, that we had this is our hypothesis. It didn't prove to be true. Now we've got to course-correct. The hypothesis that if we told people, vax it or mask it, it would encourage more people to get vaccinated, has failed. So we need to change the message.

MARTINEZ: So bottom line, Dr. Adams, vaccinated or not, what should people be doing when they're considering going out, say, to the store?

ADAMS: They need to consider where they're going, who they're going to be around, whether they're vaccinated or not and whether they can ensure themselves that the people around them are going to be vaccinated. So me personally, when I go out, if I'm going out around people who I all know are vaccinated, I - right now I don't wear a mask. If I go out around people who I'm not sure whether or not they're vaccinated, I'm going to be much more likely to wear a mask. And I'm always going to make sure I'm careful when I'm bringing my 11-year-old daughter around because something else that people need to remember is that when you talk about unvaccinated in a pandemic of unvaccinated, that includes our kids. That includes people with access issues. That includes...

MARTINEZ: Yeah.

ADAMS: ...Older and vulnerable people. So you may need to mask it and vax it the future.

MARTINEZ: Dr. Jerome Adams, former U.S. surgeon general - Doctor, thanks a lot.

ADAMS: Thank you, A. Transcript provided by NPR, Copyright NPR.