Variants, Side Effects, Transmission: Coronavirus Vaccine Questions Answered : Short Wave Can people who are vaccinated still carry and transmit the coronavirus to other people? How effective are the vaccines against coronavirus variants? And what's the deal with side effects? In this episode, an excerpt of Maddie's appearance on another NPR podcast, It's Been a Minute with Sam Sanders, where she answered those questions and more.

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Coronavirus Vaccine Q&A: Variants, Side Effects, And More

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Coronavirus Vaccine Q&A: Variants, Side Effects, And More

Coronavirus Vaccine Q&A: Variants, Side Effects, And More

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You're listening to SHORT WAVE...


SOFIA: ...From NPR.

As more and more of the COVID-19 vaccines roll out, here at NPR, we've been getting a lot of questions from y'all - questions like, if I'm vaccinated, can I still pass the virus to somebody else? What are the side effects of vaccines? How soon until we've vaccinated enough people to return to normal?

So today on the show, we have answers as part of a special segment I just did on another NPR podcast called It's Been a Minute with Sam Sanders. Yeah, I am in the hot seat for this one, y'all. If you haven't checked that show out, do it. It consistently makes me think, laugh, cry. It is so, so good. I'm Maddie Sofia, and you're listening to SHORT WAVE, the daily science podcast from NPR.


SAM SANDERS: My dear friend, Maddie Sofia, how are you? Welcome back to the show.

SOFIA: I'm doing well, Sam. How are you, buddy?

SANDERS: I'm good. I feel like the last time we had you on seems like forever ago. But I think my biggest question with coronavirus was whether I could still pet other people's dogs.

SOFIA: Oh, that's interesting. That's an interesting version of that story 'cause it was about whether or not you could kiss them on the mouth is how I remember it.

SANDERS: They're so cute. They're so cute.

Over the past few weeks, we have asked you, our listeners, to send in your questions about the vaccine.


SANDERS: All right. If folks are able to get the vaccine, can they still carry and transmit coronavirus to other people?

SOFIA: OK. So let's start off with what we know for sure, right? We know that the vaccines that are authorized in the U.S. do an excellent job of preventing symptoms of COVID, including those really scary severe symptoms. And let's just take a moment here on the show to acknowledge how monumental that is. I mean, that means fewer cases that result in hospitalizations, finally giving our health care workers a break. That means less people dying every day. I mean, that in itself is huge. And that's what the vaccines were designed and tested to do.

So as far as whether or not a vaccinated person could have the virus in their bodies and pass it to somebody else even if they don't get sick, there is some early - and I mean, like, really early - data that looks promising, some that shows that vaccinated people are less likely to have the virus in their body at all or they carry less virus. So that's all very good news. But we still don't have enough data to say for sure that the vaccine cuts down on transmission or by how much. So for now, we just kind of have to wait, which means that vaccinated folks should still mask up when they're interacting with people outside their household, especially if those people are unvaccinated.

SANDERS: If we know that the vaccine will protect you from getting severe symptoms, most likely, is it safe for two people who are fully vaccinated to hug or, like, hang out in the same room?

SOFIA: Yeah, OK - so here's what I will say about this. Because we don't know for sure if vaccinated people can carry the virus, those vaccinated people just need to think about who else they are interacting with. Right? So if you are living at home with somebody who is severely immunocompromised who isn't vaccinated, you would treat the situation differently than if you lived by yourself. Right? But if you are two vaccinated people - maybe you're even wearing masks for that added layer of risk reduction - I think you've reduced risk enough, you know, to hug it out, especially if you are two people that don't have, like, close contact with other people. I am a big proponent of risk reduction that still allows us to have some of our humanity. Right? And two...

SANDERS: Permission to hug requested. Permission to hug requested.

SOFIA: You know, two vaccinated people hugging, I would argue, is one of those situations. People will argue with me, but I would say so.

SANDERS: You know, there are so many headlines. It seems like every day there is a new variant of the coronavirus. Who knows where they're coming from? How effective is the vaccine against other and newer variants of coronavirus?

SOFIA: So this is a great question - another great question, another stumper. You know, I wish your listeners would throw me a couple of easy ones once in a while. But you know, they're too good.

SANDERS: How do you spell coronavirus?

SOFIA: (Laughter).

SANDERS: Let's do that.

SOFIA: So what I would say is this is another situation where things are developing, right? We didn't know about these variants, like, a month or two ago. But there are some data that suggest that the vaccine might not work as well for a few of those variants. But at this point, you know, most of the experts that we're talking to say they will still work. Right? Like, that's the beauty of having vaccines that are super, super effective - that even if they don't work as well against one variant, they will still provide protection. In fact, public health officials are saying that the best way to prevent these variants from really taking off in the U.S. is by having as many people vaccinated as possible. So for now, with the variants that we're seeing in the U.S., it looks like the vaccines will work well on most of them and still provide some protection on the others, which is good news.

SANDERS: All right. As more and more people in my circles get the vaccine, I'm starting to hear them talk to me about side effects. And a few folks I know said first dose was fine. Second dose, I was, like, knocked out for a day or two. Yeah, yeah. What, in general, are the side effects of the vaccine?

SOFIA: Yeah, this is a great question. I mean, I'm just really glad we're talking about side effects because I think it's important to talk about them and be transparent. So all vaccines can cause side effects, right? And that's because vaccines work by kick-starting your immune system, similar to what would happen with a natural infection. So if you do get side effects, like you get a little bit of swelling from the shot or you get a mild fever, that is just your immune system doing exactly what we want it to do. Now, rarely vaccines do cause more serious reactions, like allergic reactions, for example, so it's really important to talk, you know, about allergies with your doctor before getting the vaccine. Or, you know, if you get the shot and swelling gets worse after a day or if your other symptoms are getting more severe, lasting more than a few days, you should call the doctor.

But the overwhelming majority of the time, Sam, for the two vaccines that are authorized for use in the U.S., the most common symptoms are pain at the site of injection, swelling, as well as fevers, chills, aches, feeling tired. And some people experience very little of those symptoms. And some feel pretty uncomfortable, like you said, for a few days, especially after that second shot, because that first shot, your immune system's like, oh, hey, what's up? What's up? What's going on? And that second shot was like, oh, you again. Watch this.

SANDERS: It's like, oh, you want to move in now. Oh, my goodness.

SOFIA: Yeah. Like, now you're trying to - so that is really your immune system really being kicked into action. So like you said, I've heard of people that need to take the day off after that second shot. But here's the thing, Sam. Those types of side effects go away, right? And you know what doesn't always go away after a few days?

SANDERS: Let me take a guess.


SANDERS: COVID. You're right (laughter).

SOFIA: Yeah. You know what I mean? So I think it's important to be transparent about vaccine side effects, but also to remind people, like, for the overwhelming majority, this is not even as close to being as bad as a bad case of COVID.

SANDERS: All right. Next question for you - let's say your grandparent has been vaccinated, but you, a younger person, have not. Can you still see them? And is this scenario a little bit safer for the more vulnerable person?

SOFIA: OK. So this is a good one because it's all about assessing levels of risk. And like I said, you know, risk is not an all-or-nothing scenario, and there's a lot to work through to make these types of decisions. So let's walk through this example. So you've decided you really, really want to see your grandparent, right? Your grandparent has been vaccinated, so you've cut the risk of them getting that bad case of COVID down quite a bit. And that's big, right? You know, before going, I would probably try to quarantine for a while myself, especially if they are in a nursing home, because I don't want to bring COVID into that facility because I'm not just going to interact with my grandparent. You know, if they're in their own house, maybe that's a different story. So that's all, like, before the visit.

And then on the day of the visit, one thing I would leave your audience with is when you're seeing anybody, like, the thing to think about is, how do I cut down on the amount of air I am sharing with people. Right? That's the big - if you can carry that one thing in your head, that's the biggest thing because most transmission happens in close contact through the air, not through necessarily, like, groceries or stuff like that. So that's important to keep in mind.

So if I'm going over to my grandmother's - and she makes me call her that, Sam, by the way - the full grandmother. She demands respect. She will not be called grandma.

SANDERS: (Laughter) That's right.

SOFIA: I would be wearing a well-fitted mask, like we talked about. And if I could - and this is a huge one - I would try to take it outside if I could. If not, I would want to get fresh air circulating in the room because fresh air circulation is one of the best things you can do if you have to be indoors. And then the last thing to think about is time, right? It's not just proximity; it's also time. So I'd make the visit pretty short, too. I mean, the CDC suggests less than 15 minutes if you're indoors. But that's variable.

SANDERS: But it's Grandmother.

SOFIA: Yeah. Yes (laughter). It is. It is.

So it's just about keeping that visit as short as you can. And then after the visit, like I said, same thing as going in, I'd probably quarantine for a bit just to make sure if I got it, you know, somehow from being out and about, I don't spread it.

SANDERS: Gotcha, gotcha.

We are seeing millions of Americans getting the vaccine, which sounds good and feels good. But when do we know that we're there? Like, what percentage of the population needs to be vaccinated before you can have herd immunity?

SOFIA: Yeah. So, OK, this is, unsurprisingly, another complicated one.

SANDERS: Complicated - Avril Lavigne over here - Avril Lavigne.

SOFIA: (Laughter) Oh, my God. You know what? I'll take it. I'm not mad at that. I mean, it's not my first choice, but it's not my last. OK, OK, OK.

So if you're not familiar with this term, herd immunity happens after enough people have been infected or vaccinated until there's essentially nowhere for the virus to go. There's not enough susceptible people left for coronavirus to infect, so there aren't those, like, massive outbreaks. But there isn't one straightforward number to reach herd immunity. It changes based on a lot of things. The biggest one probably is the germ itself. So for this coronavirus, some public health officials have thrown around that, like, 70 to 85% of people would need to be vaccinated or infected to have, you know, the level of immunity that we would need.

And the difficulty in knowing the answer to your question, Sam - like, when do we reach that number? - is that we don't actually even know how many people have gotten the coronavirus, you know, realistically. There's a lot of infections that we don't catch for multiple reasons. There's a lot of people that have asymptomatic infections, you know, that kind of stuff. So that complicates it. We also don't know how long immunity lasts. So for some diseases, you get it once and you're protected for years or your lifetime. And that's probably not what's going to happen with this one.

SANDERS: Really?

SOFIA: And then, you know, we've got those variants on the scene. You've heard of those variants. So those could play a role here, too. So...

SANDERS: So there's a scenario in which this first round of vaccine that folks get - first two rounds - they'll have to be more vaccine shots down the road?

SOFIA: I mean, there's the potential for that. It would be kind of like a booster situation, perhaps. We don't really know yet. Like I said, right now it looks like our vaccines are working really well. But I know that there are some vaccine companies that are looking into developing more vaccines that would, you know, basically be kind of a booster situation.

SANDERS: Gotcha, gotcha, gotcha.

SOFIA: So I think, you know, Sam, when we ask, like, when can we reach herd immunity, when can things go back to normal - you know, I would argue - and people would argue with me again - that herd immunity might not be a reality for this virus. Like, some people might achieve...

SANDERS: (Groaning) No, you're hurting my heart.

SOFIA: No, no, no. No, it's not that...

SANDERS: You're hurting my heart.

SOFIA: It's not that bad. Some places might achieve something close to it. But this is a global pandemic, right? Like, viruses travel with people who travel. So real herd immunity - you know, global herd immunity would be tough to achieve. And so, you know, I think we have to learn how to live with this virus to be realistic. You know, the coronavirus will probably be around to some degree for a long time. And so I think focusing on what we can do - you know, getting vaccinated if you can, continue masking up, physically distancing, you know, reducing your risk as much as you can. The more we do those things right now, the faster we will get to our new normal, which, Sam, I am happy to tell you, will be much, much, much more livable than where we are now.

SANDERS: Last big-picture question for you, Maddie - like a lot of the answers around these questions are complicated and nuanced, and data and information will change over time as scientists learn more things. But is there any kind of certainty yet or any kind of forecasting on the uncertainty horizon about what our springs and summers might look like regarding the vaccine? Can you forecast what the next few months might feel like in any way?

SOFIA: Yeah, I mean - Sam, it's really, really tough. I mean, I wish I could give you a better idea of this. But what I will say is that I understand the question. And it's something that I sit with, you know, every single day. It's really hard - right? - like not to know when this thing is going to be over, like, when things are going to feel better. And what I would say is that these vaccines are going to make a huge difference. You know, when I said we're not going to be coronavirus-free, that doesn't mean that it's going to be in our face like this all the time. I mean, it could be something similar to the flu where it, you know, still impacts our lives but we have systems to live with it.

And, you know, if these vaccines are rolled out quickly and equitably, I've heard public health officials talking about this fall or maybe more the end of the year, like, really feeling a lot more of a return to normal, even if it's not totally back to normal. But I think more importantly than predicting when it will happen is just, you know, keeping the faith that it will happen, like, knowing that this will happen. We will return to this newish normal and that we have agency, you know, and that we have a say in this. So that's kind of what's getting me through.


SOFIA: We can get there.

SANDERS: What's the first thing you're going to do in that new normal that you can't do now?

SOFIA: Oof. I don't know, Sam. Oh, I don't know. I'll probably - honestly, I'll probably go see my parents, you know. Like, it would be nice to see my parents. I might also - I've never been to the Grand Canyon. I've been thinking about maybe trying to do a little traveling, do a little hiking. What are you going to do, Sam?

SANDERS: You know what I miss...

SOFIA: What?

SANDERS: ...And what I realize I miss so much? It is gathering with friends and eating. And I want, like, a nice lounge-y Saturday where we're either potlucking or the best cook is cooking and, like, 10 or 12 of us just, like, hang out for a few hours and eat and drink together. I miss that so much - breaking bread.

SOFIA: Breaking bread.

SANDERS: I miss that.


SOFIA: This episode was reported by myself and Rasha Aridi - whoop, whoop - produced by Brit Hanson and Jinae West, edited by Gisele Grayson, Viet Le and Jordana Hochman. I'm Maddie Sofia. Thanks for listening to SHORT WAVE from NPR.


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