Comparing COVID-19 Vaccines

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Brian Lehrer: Brian Lehrer on WNYC. Coming up next hour, it's our weekly Ask The Mayor segment, but right now, it's time for ask a virologist with Dr. Angela Rasmussen at 646-435-7280. Maybe you want to ask a question about vaccines, maybe you want to ask a question about variants, maybe you want to ask about double masking and the quality of different kinds of masks more in the news these days, whatever, 646-435-7280, 646-435-7280.

As your calls are coming in and before we bring on Dr. Rasmussen, some of the latest COVID vaccine news this morning includes that an FDA advisory committee is now officially scheduled to meet on February 26th to look at approving the use of the one-shot vaccine from Johnson & Johnson. Pfizer and Moderna vaccines are about 95% effective when it comes to preventing even moderate cases of COVID they have found in trials.

Johnson & Johnson, it appears to be 65% effective, but that could be in this leading stat because it still appears to be extremely effective against severe cases. There's breaking news just a little while ago about the AstraZeneca vaccine which has now been found to be protective against the Coronavirus variant first seen in the UK.

That, if true, is really good news. With all of that as prelude, joining me now is Dr. Angela Rasmussen, virologist and affiliate at the Georgetown Center for Global Health Science and Security. Dr. Rasmussen, thanks for doing this. Welcome back to WNYC.

Dr. Angela Rasmussen: Thanks so much for having me back, Brian.

Brian Lehrer: Can we start with that brand new AstraZeneca vaccine news yet? Have you even seen that yet? How do they tease out whether any of these vaccines are effective against the new variants?

Dr. Angela Rasmussen: This is a really complicated question. Part of it is that if you want to look at vaccine efficacy against the new variants, you really have to make sure you're conducting your clinical trial in a place where those variants are circulating. Right now, even though the variants have been detected, many places all over the world, including throughout the US, there are not many countries where those vaccines are actually circulating widely in the populations.

One of those countries is South Africa. Trials that have been conducted in South Africa are able to actually look at this variance. That's where we're seeing some of this clinical trial data about vaccine efficacy specifically with its ability to protect against the B1351 variant that circulating there.

Brian Lehrer: How about the Johnson & Johnson vaccine? I'm getting the sense from some science people that it's been under-reported in terms of its effectiveness that when we say a top-line 65% effective, and we've all heard 94% effective for the Moderna and the Pfizer, it really underplays how good the Johnson & Johnson one-shot vaccine is. Is that your take?

Dr. Angela Rasmussen: That is my take. I think that this has been really unfortunate and it really shows how difficult vaccine trials are to report on. One of the things you are correct in saying that it was less efficacious protecting against all symptomatic COVID-19, but it was extremely efficacious preventing severe COVID-19. That was actually an endpoint that wasn't studied in the Moderna or Pfizer trials.

Johnson & Johnson was completely effective. There were no deaths as a result of people who were vaccinated, meaning that this vaccine is also extremely efficacious. It has one other major advantage over the Pfizer and Moderna vaccines. That is that it's only one shot and it also doesn't require long-term ultra-cold storage the way that the mRNA vaccines do.

I think that we should be celebrating the Johnson & Johnson news because it means that we have one more fantastic vaccine to add to our toolbox. This is also going to make it a lot easier to vaccinate people who are either in areas that make it difficult for vaccinators to get to both in the US and abroad and areas that don't necessarily have the same type of cold chain infrastructure that larger cities, for example, will have. I think overall, the Johnson & Johnson news is fantastic.

Brian Lehrer: That's severe disease prevention. That's really the ballgame, isn't it? Because with any other cold or flu that's going around, if you get it, you get it. The problem with COVID is that so many people wind up hospitalized or wind up dying. Any vaccine that prevents that, that's the ballgame, right?

Dr. Angela Rasmussen: That's absolutely correct. The thing with COVID is that it's really a numbers game. SARS-CoV-2 is very transmissible. We've seen it really just tear through populations, especially when people aren't implementing precautions to reduce transmission and exposure. Out of those people who get it, many will not have severe disease, but enough people get it enough people have to go to the hospital, then the hospitals start to become overwhelmed.

If we are at hospital capacity, our already fragile healthcare system is really going to be pushed to its breaking point. Making sure that we can protect people from a more severe outcome where they have to be hospitalized and where they might even die from having COVID is really great both for people receiving the vaccine as well as for public health at large. I think that vaccines that can reduce costs and deaths are really, as you said, the ball game.

Brian Lehrer: All right. Listeners, it's Ask a Virologist. The virologist is Dr. Angela Rasmussen from Georgetown University. Kyle in Astoria, you're on WNYC. Hi, Kyle.

Kyle: Hey, Brian. First-time caller. Thank you so much for taking my call. This is for Dr. Rasmussen. I wanted to ask about masking and specifically less about double masking so much as getting the KN-KS series of masks. I know that there's been some articles and popular media sources about getting those masks.

If you go on places like Amazon, which is where a lot of these things are available, I just wanted to know as a consumer, how fussy we should be when making the selection, like FDA approved stuff, if it's sold through an independent retailer is often sold out. When it comes down to it to something that you'd like platinum seal of approval for it to be more effective and a surgical mask or a surgical basket top of a cotton mask? That's my question.

Brian Lehrer: Thanks, Kyle.

Dr. Angela Rasmussen: That's a fantastic question, Kyle. There has been a real problem with counterfeit or low quality and KN95 masks or KF94 masks being sold through retailers like Amazon in particular. The trouble with this is that N95 masks are certified by NIOSH, which is an agency in the US that basically does quality control for these masks to make sure that they are adhering to standards stuff that you buy off the internet. It's anybody's guess because there's not really a seal of approval that any of these masks will get.

I've personally advised my parents to buy KN95 masks from a retailer like a drug store, Costco, Walmart. Places like that are going to probably between better quality control with the supplies that they have, even though it still won't have that NIOSH certification. The other thing to think about when you're looking at a KN95 or a KF94 mask is you want to make sure that it's fitted.

Normally, when we wear N95s in the hospital for my physician colleagues or for me in the lab, we have to get fit tested every year to make sure that the mask is forming a tight seal around your face. That's really how those masks, those respirators provide that level of protection. If you do buy a KN95 mask from anywhere, you're going to want to at least feel around the edges to make sure that it's sitting flush with your face.

If you have facial hair, you're going to be able to get a complete fit. For people who do have that, who aren't able to do fit testing, or who aren't noticing that their KN95 is fitting flush to their face, I would recommend putting a cloth or a surgical mask over the top to pull that mask against your face so that it fits more tightly.

I think for me, we unearth some old N95's from a home improvement project from years ago, but I really only wear those in situations where I know that I am going to be in an enclosed space for a long period of time, for example, the last time I flew and I don't do that very often.

When I go to the grocery store or run errands, I usually just wear a surgical mask that I make sure is fitted to the bridge of my nose and that there's not huge gaps on the side of it. That should be fine. I think that it's also fine to double mask. A lot of this has to do with what you're comfortable with, what is wearable to you? Not everybody is going to be able to tolerate wearing two-cloth masks or a cloth mask and a surgical mask for a long period of time.

The important thing is that you're wearing a mask that fits your face relatively well and that hopefully is layered and ideally has a filter layer in it. You don't want to be wearing one of these one-layer net gators that isn't necessarily going to be completely tight on your face. You want to be wearing some kind of mask that does form as good of a seal as possible around your mouth and nose and that also has multiple layers to filter those droplets that you would be inhaling better.

Brian Lehrer: Kyle, great question that prompted a really helpful response. Thank you for that. Dr. Rasmussen. Mary in Brooklyn. You're own WNYC. Hi there.

Mary: Hi, Brian. Hi, Dr. Rasmussen. I'm very curious to ask what is the process by which virologists and public health folks are going to be able to figure out whether the current vaccines offer, I think, it's called sterilizing immunity, or simply put, whether they're going to protect people from being asymptomatic carriers and spreading the virus. When I look around online, I don't see any answers, not only to like what we know so far but how are we going to know and how long is that going to take? When might we start to see data coming in?

Dr. Angela Rasmussen: Mary, that's a fantastic question. There's a couple of different ways that we can get this type of evidence. One way is to actually just look in trial participants or vaccinated individuals at how many of them become infected will test positive for having COVID after receiving the vaccine. AstraZeneca has already looked at that a little bit in one of their trials.

They have been taking weekly nasal swabs from participants and doing PCR testing on them and seeing how many people in the vaccinated group versus the placebo group actually tested positive for COVID after receiving the vaccine. That's one way to look at whether the vaccines can protect against infection. Looking at how well they reduce transmission is another story. The way that you would look at-- There's a couple of different ways that you can look at that, first of all.

You can start measuring viral loads from those same types of experiments that I was talking about and try to figure out whether if people who are vaccinated do get infected. Are they shedding as much virus when they are infected as people who have not been vaccinated? You can indirectly try to infer whether or not those people would be as transmissible as unvaccinated people.

Another thing you can do is look at it in terms of the epidemiology. You can see if vaccinated people over time are associated with any new clusters of transmission. If they are the index case, for example, their entire household getting infected. That will take a little longer to gather because that requires quite a bit of on the ground epidemiology work.

You can also look at it at the country level. People are starting to look at this in Israel, for example, where they've already vaccinated a large portion of their population. They have seen reduction in cases suggesting that transmission might be slowing down. The trouble with that is that they haven't vaccinated their entire population and they've also had a lockdown.

It's really hard sometimes to try to dissect out the effects that the vaccine is having in relation to all these other variables, the other interventions that are in place. I think over the next month or two, we're going to be seeing more of all of these different lines of evidence that will really tell us, I think, how well the vaccines will both prevent infection for people who receive them, but more importantly, will curb transmission at the population level because that's the really important question, I think, that we need to be thinking about long-term.

If everybody's getting vaccinated and we know not everybody probably will, then how likely is it going to be that people who are vaccinated are going to be able to transmit this to people who are not? I think that's the real question. I hope that we will have that information, or we'll at least know a lot more about it in the next month or two.

Personally, I can't say any more than any of my colleagues because we don't have the data. Personally, I think that vaccines this efficacious will probably have some impact on transmission. I don't think that we're going to be looking at the worst-case scenario in which everybody's vaccinated and protected against disease, but everybody's also getting infected and shedding asymptomatically all over the place. I think that that's just very unlikely. The short answer is, give it a couple of months.

Brian Lehrer: Cindy in Montclair, you're on WNYC with virologists Dr. Angela Rasmussen. Hi, Cindy.

Cindy: Hi, good morning. Thank you, Brian, as always for 20 years listening to you. I so appreciate this. My question is two-fold. On one hand, I'm wondering, there's so much competition, there's a lot of money to be made with vaccines. At what point do these companies collaborate where we have, it's not only 93, but 94% advantageous?

It's not only efficacious. It's not only something that you give in one shot or two shots. Is there a point at which they want to collaborate for the good of humanity? Number one, and number two, I forgot my damn question. Go ahead with number-- I can't remember the second part but-- [crosstalk].

Brian Lehrer: That's right. I'll come back to you after Dr. Rasmussen answers your first question. I would just follow-up on that question by saying, is it necessarily what we want for pharmaceutical companies to collaborate, or maybe the competition that we've been seeing that develops these various vaccines produces results in the long run?

Dr. Angela Rasmussen: I think that I'm not entirely sure what the caller means by collaboration, but I think that there's a couple of places where collaboration is potentially very helpful. One is in the area of manufacturing. We've already actually seen this start to happen where vaccine manufacturers whose vaccines either failed or have been delayed have agreed or are making deals with the manufacturers who do have authorized vaccines or vaccines that are very likely to be authorized soon to manufacture those vaccines, to increase the authorized vaccines manufacturing capacity. I think that that is fantastic and we should be seeing more collaboration like that.

In terms of collaboration over what are called heterologous vaccine regimens or a mix and match vaccine approach, which I think the caller might also have been asking about, I think that we'll be seeing more about that, particularly because of these variants. Most of the manufacturers have announced plans to reformulate their vaccines to address the variance for the Moderna and Pfizer mRNA vaccines.

That's actually technically very easy to do. There's another technical issue as well. The AstraZeneca and Johnson & Johnson vaccines are what are called viral vectored vaccines. They're very effective in many cases, but they also are using a virus called an adenovirus to deliver the spike protein from SARS-CoV-2 to the person being vaccinated. That means that people who receive those vaccines will not only develop antibodies to spike from SARS-CoV-2, they'll develop antibodies against the vaccine itself because it is another type of virus.

That means that you might not be able to boost as effectively with those viral vectored vaccines, at least the ones developed using the adenovirus vector platform. We may be looking at a situation if we continue to see variants emerge, and we do need boosters where we have to boost with a different vaccine platform that won't have those problems with vector immunity.

I think that going forward is going to be really important for all of these vaccine manufacturers to collaborate with each other looking at these so-called heterologous dosing regimens or mix and match boosting because I think that we may be in a situation where every couple of years or at least once more we are needing to vaccinate people again to account for these variants that are emerging.

Brian Lehrer: Cindy, did you remember your second question?

Cindy: Yes, I did. The mix and match part of it was hard for me to articulate, but I was wondering what would happen if you take one and then a variant comes around. Also, how do we even ever have a chance to pick? I'm waiting for Kmart to give me whatever they have.

Our local Kmart here in West Orange is where they're going to administer them. I don't have a choice. I can't decide whether it's the Pfizer 30% or the other. They have different formulations which I've actually read into, but I don't know that I have a say in it. Is my doctor going to support me in that or am I just lucky to get anything?

Dr. Angela Rasmussen: Right now, as far as I'm aware, most people are getting the second shot of the first shot that they get. Nobody is recommending a heterologous boosting regimen with what the example would be like, you get your first shot of Pfizer and then you get your second shot of Moderna. Now, that's not to say that that's not happening in some places. Overall, I think people are getting Pfizer and Pfizer or Moderna and Moderna.

I think that going forward, we may see that you can mix and match these things and that would be great. Certainly, as supply increases, people may have an option to choose one vaccine or another. Right now, though, I'm with you. I will take whatever vaccine I can get when it's my turn to get one including Johnson & Johnson if it's authorized then. I was saying earlier, I think that the Johnson & Johnson vaccine is a great addition to the vaccine toolkit. Probably, I would take AstraZeneca as well once that is evaluated by the FDA if it also receives authorization.

I think though that as supply increases, we will have more of an opportunity to pick which vaccine we might be getting. There may even be circumstances that some vaccine platforms are more appropriate for certain people than others. We just still need to get data on all of that, and of course, we need to increase vaccine supply as well.

Brian Lehrer: Here's another second dose question from Giovanna in Washington Heights. Giovanni, you're on WNYC with Dr. Angela Rasmussen. Hi?

Giovanna: Hi. I was wondering if Pfizer and Moderna have looked into delaying the second shots, the benefits of doing that. The AstraZeneca people have found that you get a much better immune response because of the delay. There was a British virologists on the BBC explaining that the initial response, there are efficient and less efficient cells coming to attack, but if you wait the efficient ones to take over until the response is better.

Brian Lehrer: You mean wait longer than the three or four weeks that they're now being admitted after?

Giovanna: Yes, they were mandated in England to do that because they wanted more first shots.

Brian Lehrer: That's, of course, is a controversy here too. Dr. Rasmussen, do you know that science?

Dr. Angela Rasmussen: That is very much a complicated and emerging area of research. That is true for the AstraZeneca vaccine that was a finding that they just recently shared that increasing the interval between the first and second shot for the AstraZeneca vaccine actually seemed to improve it, or at least improve the immune responses that it elicited after the second shot.

It's not clear though whether that would also be the case for the Pfizer and Moderna shots. One of the reasons for that is that, they are a completely different vaccine platform. The AstraZeneca vaccine is an adenovirus vectored vaccine. It uses a virus to deliver the spike protein for your immune system to look at.

It's possible that that longer interval makes vector immunity that I was just talking about a little bit less of a problem. Also, those viral vectored vaccines are replicating viruses. They don't go through their complete replication cycle and make new virus, but they do engage in some of those viral replication processes which can trigger different parts of your immune system.

The Pfizer and Moderna mRNA vaccines just express the spike protein. There's no viral replication occurring at all. When you give those vaccines, they might trigger slightly different immune responses as a result. Ultimately, with Pfizer and Moderna, we've only looked out to about a six-week interval between the two shots.

I'm very reluctant to recommend going beyond that, just because there is some evidence that neutralizing antibodies will go down very quickly after that first shot. I think, for now, we should definitely look into this, we should do more studies.

Actually, in the UK, they are essentially doing a natural experiment because they've advised people that they can wait 12 weeks to take the second shot of the Pfizer vaccine for people who are receiving that one there. I think we just need more data before we should be making that recommendation since we just don't know.

Brian Lehrer: One more and it's not on vaccines. Brian in the Bronx, you're on WNYC. Brian, I'm so glad you're calling with this question. Hi?

Brian: Oh, hi. Can you hear me okay?

Brian Lehrer: Yes, ye got you.

Brian: If you look, just at a world COVID tracker, Wikipedia, the mortality rate per million in China is three, the mortality rate in the US is 1,300, and that has nothing to do with the vaccine. It seems like they're doing something we're not doing. Why are we always talking about vaccine? Because they seem to kind of being successful.

Brian Lehrer: Brian, thank you very much. I thought he was going to go one step further, so I'll have this piece. Treatments, which I don't know if science, the pharmaceutical companies have focused so much on vaccines that they haven't been working on treatments. How would you answer Brian's question and maybe my tack on too?

Dr. Angela Rasmussen: I'll address treatments in a moment, but there's one big difference between us and China. We have a lot more SARS-CoV-2 circulating here than they do. This really illustrates one point and that is that you actually don't need vaccines to control COVID in your country. China did it in a way that's probably not very feasible, certainly not in the US, but in most countries.

That is that they had a very, very draconian extended lockdown where people were in their homes not able to leave for any reason for months in some cases. I think that that's not very practical. If you look, there's a number of other countries that have used a combination of different non-pharmaceutical approaches to control COVID.

Australia, New Zealand, Taiwan, Vietnam, South Korea, all of these places have really been very effective at controlling COVID. I'm using a combination of testing of isolation and quarantine, contact tracing, these basic epidemiological approaches, and to some degree, travel restrictions, or at least well-impremented travel restrictions.

Brian Lehrer: You can without the vaccine. One quick follow up, and we have 30 seconds in the segment. I've seen some people on TV recently say, "If only everybody would really mask up for one month, we could be done with the virus in this country." Do you agree?

Dr. Angela Rasmussen: I agree to a point. I think that masking alone is not going to be enough. I think we also need to be very conscious about distancing, about avoiding gatherings, about implementing ventilation, about avoiding crowds, things like that. I think that a combination of those types of targeted interventions should be implemented right now while we are not vaccinating enough people.

The combination of vaccination and those non-pharmaceutical measures will really, really help us. It's been a little frustrating that the message has been just about vaccines when we should still be encouraging people to take these other precautions to get transmission down.

Brian Lehrer: Dr. Angela Rasmussen, virologist and affiliate at the Georgetown Center for Global Health Science and Security. Thank you so much for so much great information. We really appreciate it.

Dr. Angela Rasmussen: Thank you so much for having me again, Brian. Always a pleasure.

 

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