Why A COVID-19 Vaccine That's Only 50% Effective Could Still Help Stop The Pandemic : Shots - Health News Scientists are racing to develop a vaccine that proves "safe and effective." It may not prevent infection in everyone who gets it, but it still could eventually stop the pandemic. Here's how.
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A COVID-19 Vaccine May Be Only 50% Effective. Is That Good Enough?

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A COVID-19 Vaccine May Be Only 50% Effective. Is That Good Enough?

A COVID-19 Vaccine May Be Only 50% Effective. Is That Good Enough?

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  • <iframe src="https://www.npr.org/player/embed/911987987/912612344" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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DAVID GREENE, HOST:

We have now surpassed 6.5 million cases of the coronavirus in the United States. The virus is still circulating widely, but new cases are down significantly, dropping about 20% over the last week or so. NPR's Allison Aubrey joins us, as she does on most Mondays, to talk about where we are in all this. Allison, thanks for being here.

ALLISON AUBREY, BYLINE: Good morning, David.

GREENE: So I so want to believe that these numbers are suggesting something encouraging here.

AUBREY: Yes.

GREENE: I mean, am I safe feeling a little encouraged about this decrease?

AUBREY: You know, yeah, I'd say over the last week, there've been about 35,000 cases per day documented - new cases. That's a significant decrease from the 60,000 we were seeing back in July. Deaths are declining, too. So, yes, there are signs of improvement, but the pandemic is not behind us, right? I mean, as we head into fall, infectious disease experts say there's a good chance we'll see an increase in cases as people, you know, spend more time congregating inside. And given that we don't yet have a vaccine, it's really important to remain vigilant.

GREENE: Well, I mean, let me ask you about that vaccine. What is the latest?

AUBREY: Yes.

GREENE: And what are the chances that we are going to have a vaccine that is effective enough anytime soon to make us feel better about this?

AUBREY: You know, it's not clear how effective the vaccine will be. But here's a bit of a reality check. Anthony Fauci has tried to set expectations by saying that the vaccine may only be about 50% effective. You know, everyone hopes for a higher rate of efficacy. But, in fact, the FDA has said that if a vaccine is shown to be safe and at least 50% effective, it could be approved.

GREENE: I mean, that's quite a reality check. I think a lot of us were thinking, like, it might be safe to - you know, with our loved ones with comorbidities, we can go visit them. It sounds like...

AUBREY: Right, thinking of it as a magic bullet, yeah.

GREENE: Yeah. Not that at all, it sounds like.

AUBREY: You know, it's not. It means if a hundred people get the vaccine, 50 of them could still end up getting infected with the virus. Now, there's still benefit there. I mean, infectious disease experts are hoping that it would be similar to the flu vaccine in terms of reducing the severity of illness, meaning that, you know, if you're a person who gets the vaccine and ends up getting sick with the virus, the hope is you won't get as sick. You know, you'd be less likely to end up in the hospital. But it's sort of too soon to say the extent to which this will be the case. The other reality check, David, is that lots of people, the majority of people need to be vaccinated in order for us to reach a sort of herd immunity to this virus.

GREENE: Well, and that seems like a real potential problem because you have a lot of Americans saying that they're very hesitant to get a COVID-19 vaccine whenever it is approved. Is that changing? Are efforts to get more people on board effective?

AUBREY: You know, an NPR/PBS/Marist poll found back in August that more than a third of Americans, some 35%, say they won't get vaccinated when a vaccine becomes available. And in recent weeks, David, with concerns about political pressure to have a vaccine before the November presidential election, you know, it seems that just - it has made more people hesitant.

I spoke to Robert Winn about this. He's a physician in Richmond, Va. He's been advising faith leaders at a number of black churches. He says he definitely hears this hesitance in the African American community he's a part of. He says he's not at all surprised that Black patients are among the most reluctant to participate in clinical trials of the vaccine.

ROBERT WINN: And, you know, this is built on a history of having almost no to little trust to begin with. I mean, if you think back to, you know, the United States Public Health study in 1932, otherwise the Tuskegee study, I think that that history now, on top of an eroding sense of trust and an eroding sense of where you can get accurate information, is really adding to a - not an illogical sort of mistrust and enhanced distrust of the system.

AUBREY: And he says this is really very unfortunate, right? His take is that this distrust is very widespread, well beyond the African American community. So the message that he's trying to get out is this.

WINN: Do we need a vaccine? We absolutely need a vaccine. A good vaccine does two things. It prevents people from getting, you know, the infection, and it reduces the symptoms if you get it. But now there is resistance and mistrust and distrust about taking even a good vaccine at this moment. And so I think it's just - it has been the most disheartening couple weeks for me.

AUBREY: You know, he says there's just such a loss of trust.

GREENE: Yeah, a loss of trust and entrenched distrust.

AUBREY: Yeah, yes.

GREENE: I mean, can trust be rebuilt on something like this?

AUBREY: I mean there's an attempt to do this. Nine companies, including the CEOs of AstraZeneca, Moderna, Pfizer, signed a safety pledge last week promising not to submit their vaccine candidates to the FDA for review until their safety and efficacy is documented, really nailed down. But Robert Winn says, you know, there's this sentiment out there that no one wants to volunteer to be first. They want to see how the vaccine works for others. He says he hears this a lot.

WINN: It might work, but let it work on other people first. And then we might decide to jump in. And I think the unfortunate thing is that if we all just wait for somebody else to get it done, it just delays us getting a vaccine that works, which means more people are going to get sick, means more people are going to die. I mean, it's just the fact of how this all works out and plays out.

AUBREY: Now, the first group to be offered a vaccine will likely be essential workers, health care workers. So clearly, trust within that community is key.

GREENE: Can I just ask you - I mean, this is something we've been covering at NPR a lot - I mean, the situation at college campuses that have been...

AUBREY: Sure.

GREENE: ...Reopening. You had some that reopened and then had to close for in-person learning, I mean, really quickly.

AUBREY: Right.

GREENE: Those COVID cases shot up. What are we looking at right now?

AUBREY: You know, I think it's highly variable. There have been more than 80,000 cases reported on campuses. I spoke to Aaron Carroll about this at Indiana University. He's a physician. He says the infection rate in dorms there is quite low. And there's actually no evidence of spread inside classrooms, where students are distanced and masked. But in the Greek system - so sororities and fraternities - there are very high rates of infection.

AARON CARROLL: It depends week to week. We have some fraternities where I think it's gotten above 80%, you know, where it's very likely that, soon, all of them will be infected if they are not already. Overall, we've had no significant illnesses, no hospitalizations at this point. But the spread in our Greek system has been significantly higher than we would like.

AUBREY: So this is not an environment where it's easy to stop the spread.

GREENE: NPR's Allison Aubrey. Thanks, Allison.

AUBREY: Thank you, David.

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