Vaccinating kids will be very important in getting to herd immunity: Expert

Kristen Choi, PhD, MS, RN, Assistant Professor, UCLA School of Nursing, joins Yahoo Finance’s Kristin Myers and Alexis Christoforous to discuss the latest on the coronavirus.

Video transcript

KRISTIN MYERS: Welcome back. It's likely that people will need a coronavirus vaccine booster, at least that's according to Pfizer's CEO. So let's chat more about that. We're joined now by Kristen Choi, assistant professor at UCLA's School of Nursing.

So Kristen, we're hearing from Pfizer's CEO that folks will need a third shot. As we know, Moderna and Pfizer need two shots in order to be fully vaccinated. We'll need to get a vaccine booster. I'm curious to know how long you think folks are going to need this booster regimen. Is this something that folks are going to have to do every single year, like the flu shot? Or might this be something that might be short-term until we can get boosters every five or 10 years, perhaps?

KRISTEN CHOI: Sure. Well, first, thank you so much for having me on this afternoon. You know, the booster shots and how frequently will we need it is really still something that's a major question. We don't know for sure what's going to happen with coronavirus variants. We have seen a couple of big dominant variant strains emerge. But it's difficult to predict at this point whether those strains will take hold in the population or whether, with our current vaccination process, we'll be able to sort of tamp them down.

At this time, both Pfizer and Moderna are testing boosters of the vaccine. At this point, also, though, we know that the original two-dose regimen has seemed to be fairly effective against some of the dominant strains we're seeing, which is really good news. At this point, we sort of need to wait for the research to bear out whether or not these vaccines will be effective and if they're needed. And at the moment, our priority still is just getting those first and second doses to people that haven't gotten them yet.

ALEXIS CHRISTOFOROUS: What do you make of these breakthrough numbers that we're getting now, Kristen, about, you know, people who have been fully vaccinated and still getting COVID? I know the numbers are small, but it is happening. Is that to be expected?

KRISTEN CHOI: Yes. We know that the vaccines even though they are very effective-- in the case of Pfizer Moderna, 90% to 95%-- they're not perfectly effective. And we do still have some cases of people who contract the coronavirus even after being vaccinated. These cases are very rare. And the good news about our vaccines-- all three of them, including Johnson & Johnson, which is now paused, is that they are very effective at preventing severe COVID.

So even if you contract COVID after getting vaccinated, which no one wants-- it's rare, but it can happen-- you're very unlikely to be in a situation where you would need to be hospitalized or you are at risk of dying. But for most people, these breakthrough cases are something that most people can expect not to happen to them. The vaccines are very, very effective, for the most part.

KRISTIN MYERS: Kristen, I'm curious to know how concerned we should be going forward, in terms of vaccine hesitancy about these blood clots. Johnson & Johnson, that vaccine was paused. And right now, the demand is still exceeding the supply. Are you at least hearing from patients at all a lot more concerns about the vaccine? And do you think that that might play out perhaps a little bit later on in the year, as folks start refusing to take it?

KRISTEN CHOI: Yes, I am concerned about vaccine hesitancy in the US. Right now, we are still in a place where sort of demand exceeds supply and there are more people that want the vaccine still that need to get it, which is great news. But I think we're pretty close to seeing a place where that supply-demand relationship is going to shift. And we're going to be in the position of getting vaccines out to some key groups that haven't gotten it yet.

And there are a couple of groups that I'm especially concerned about, when it comes to getting the vaccine. One is kids and teens. We know that Pfizer and Moderna are both testing their vaccines for much younger kids. We've seen some really promising data from Pfizer about the vaccine in adolescents, but kids are going to be a very important group for us to vaccinate to get to herd immunity. And we know that with vaccines being new, it's going to be really important to reach parents and help them understand that the vaccines are safe and effective for their children.

Another group, interestingly, is men. There have been some interesting data points coming out showing that men are less likely to get the vaccine than women. We also know, unfortunately, that men are more at risk for severe COVID than women. So it's going to be very important for us to think about outreach to some of these groups that might not want to get the vaccine.

In terms of the Johnson & Johnson, that concerns me as well. I think that the pause to review these cases of these very rare blood clots was probably the right thing to do. But at the same time, we want to make sure that people know that these-- the risk of the blood clots is so rare and our risk for COVID is so much higher that it's likely that Johnson & Johnson will still be a vaccine that's worth taking for a lot of people out there.

KRISTIN MYERS: Kristen, we heard that you are actually are in the trial for that booster vaccine. Of course, you wouldn't know if you received the third shot or if it might be nothing but-- more than saline. But curious to know how you're feeling, if you've received the third shot as yet, or if you have any insights from being a participant of that trial you could share.

KRISTEN CHOI: Yeah, I do. So I've talked with your audience before about being a part of the Pfizer study last summer. I was in the phase-three clinical trial and was fortunate to receive the active vaccine. A couple of weeks ago, I had the opportunity, through that same study, to get a third-dose booster as part of a small study of safety and tolerability of a booster shot.

I got that booster dose a couple of weeks ago here. And so far, I'm feeling fine. I had some mild symptoms after the vaccine, similar to what people see in the first or second dose. But you know, I feel really fortunate to be a part of this study and hopefully help learn whether this vaccine will work for a lot of people and whether it works against some of the variants that we're seeing. But I feel good so far.

ALEXIS CHRISTOFOROUS: That is great news, and thank you for being part of that trial. It's so important that they have people to be able to-- to be willing to be tested for things like this, so thank you. You know, there's been some confusion, I guess I'll say, about people who've been fully vaccinated and whether or not they should be getting tests for COVID. Because, you know, you can be asymptomatic and still get it. We're seeing that there are these breakthrough cases. So how important is it that folks who have been fully vaccinated do get COVID tests, especially if they're going to be around younger people who have not yet been vaccinated?

KRISTEN CHOI: Sure. I think that COVID testing is still something that is a very important tool for public health that we all need to be participating in. Again, at this point, we are still not at that level of herd immunity, and we know that there is still a fair amount of coronavirus circulating in our community. Once we get to the point of herd immunity, I think that's where we'll be able to really see reduction of some of these measures, like testing and masking that we currently still follow. But until we get there, and we still have a little ways to go, it is important that people continue to wear masks, social distance, and get tested.

And certainly, for folks who are interacting with groups, who are around people that may not have been vaccinated, getting those tests is really important. Testing has become more and more accessible. It's fairly easy to get a test in most states now and so certainly would encourage folks to continue to be tested regularly, especially if they're going to be around people that are not vaccinated.

KRISTIN MYERS: All right, Kristen Choi, assistant professor at UCLA's School of Nursing, thanks so much for joining us today.