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Bonnie Maldonado: The science is clear. Vaccinations save lives.

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Bonnie Maldonado: The science is clear. Vaccinations save lives.

An expert in infectious diseases says that vaccinations are more powerful than ever, but better communication by the medical community is needed to combat misinformation.

Vaccinations carry very little to no risk for the vaccinated. | Stocksy/Cara Dolan

Vaccinations carry very little to no risk for the vaccinated. | Stocksy/Cara Dolan

Stanford professor Yvonne “Bonnie” Maldonado is a medical doctor and an expert in pediatric infectious diseases.

She has been fighting and preventing disease her entire career. She says that vaccinations have made remarkable progress in recent years and yet, despite well-known programs that have virtually wiped out once-dreaded diseases like measles, smallpox and polio, a more insidious foe than these diseases has appeared — misinformation that sows confusion, fear and distrust of vaccines in the general public.

The result has been a worrying reappearance of some of the diseases society has worked so hard to eradicate. But the science is clear: Vaccinations save lives and carry very little to no risk for the vaccinated. Meanwhile, scientific advances are making vaccines more effective and less risky by the day.

There is no magic solution, Maldonado says, but evidence suggests that a more personalized communication approach could help by avoiding stigmatizing naysayers in favor of greater understanding and cooperation with dubious audiences. In working with the public, she says, medical providers remain the first and best line of communication with both the scientific knowledge and the public trust to deliver these life-saving messages.

In this episode of Stanford Engineering’s “The Future of Everything” podcast, Russ Altman and vaccination expert Bonnie Maldonado for a clear-eyed look at the future of vaccines.

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Russ Altman: Today, on “The Future of Everything,” the future of vaccines.

Now, vaccines have been in the news recently. Unfortunately, much of the attention has focused on the declining rates of childhood vaccination, that are causing suffering for individuals, often children, who contract diseases that are preventable, and can have long term consequences, as well as suffering for society, where we risk the return of diseases that we thought had been successfully either eliminated or contained.

But there’s other news in vaccines. Researchers and companies are working very hard to create new ones for emerging infections that enter into the human population. These include deadly viruses, like ebola, viruses that can cause birth anomalies, like zika, and viruses like the flu, that vary in intensity, but always put millions of people at risk, especially vulnerable populations. And sometimes has the potential to cause very deadly epidemics, as it did in 1918 to 1920, when an estimate of about 500 million people were infected and perhaps as many as 100 million people died. 

There are many challenges to this successful creation and deployment of vaccines. We need to understand the basic biology, how does that virus or bacteria work? It often requires a deep understanding of the life of the bacteria to look for places, or virus, to look for places where we can take advantage of these vulnerabilities to remove them. The virus, the vaccines must work, they must be safe, and they must be accepted by physicians and patients.

Dr. Bonnie Maldonado is a professor of pediatrics and health research and policy, and an associate dean for faculty development and diversity at Stanford University.

Bonnie, you have recently been focusing some efforts on measles, a disease which was rampant until the late 50s and 60s when effective vaccines emerged, and we basically saw none of it. Now, however, we’re hearing about sporadic outbreaks and some heartbreaking stories about the people affected by the measles. What has happened with measles, and what have you found in your own work?

Bonnie Maldonado: Well, thank you, Ross. It’s a very timely topic. I feel that the measles is a real case study for the rise of anti-science sentiment, and an anti-fact sentiment in the public, partially as a result of social media and partially as a result of our own failure to communicate the benefit of some of these advances that many people take for granted today. For example, when you and I were young physicians, we saw lots of diseases that killed children and adults, all the time. I can say that every week, we saw terrible cases come in to the hospital, here at Stanford, and wish that there was something we could do to prevent these diseases, not just treat them.

And what we’re seeing now is we have had such a massive reduction in the prevalence of these infectious diseases, especially in the U.S. and other developed countries, that most people don’t recognize them as a risk. And, hence, they feel that the benefits of a vaccine are probably not that important to them because it’s always a risk-benefit calculation and they see the risk as being close to zero, or zero, which it definitely is not.

Russ Altman: Right, and so in the olden days, you had neighbors and friends and family who had suffered from these diseases, and it was miraculously good news that you could avoid it in your children, and now that it a much less present, are there other reasons for the hesitation? You made a mention of social media, you made a mention of anti-science sentiment, how do you put this all together and is it, it seems that it’s happening, not only for measles, but for many of the other vaccines, as well.

Bonnie Maldonado: Yeah I think, so, first of all, I’m an epidemiologist and so I like to look at everything in terms of an epidemiologic perspective. I think there is an epidemiologic curve to anti-vaccination sentiment, and that is exactly what I said.

First, you see a disease, people get panicked, I think you remember in 2009, when we saw the pandemic flu, everybody lined up for miles and miles to get that vaccine. You don’t see people lining up for miles now to get flu vaccines, but when they knew people were dying, they were worried. And then you see the development of vaccines and preventive measures, then you start seeing a reduction in these diseases, and then, again, as I said, people forget and they discount the disease.

The other issue though, is we’ve always had people who have doubted, and that’s OK, our place as scientists and physicians is to explain to the public what facts we have discovered, what facts would like to know about, and what we just don’t know. And what’s different today is that social media really amplifies certain voices above others and that is the core groups of people who have very fervent ideas, can really have a huge platform. And it’s very difficult, when you’re on a media platform, social media platform, to distinguish between real and fake. And I don’t even like to say the fake piece, but really, to understand what is the truth.

Russ Altman: That’s right, and so these are well-meaning people who are, in many ways, are confused by signals that are coming at them from all areas of life, and just trying to make the best decision for their children, in many cases.

So, where did this, I don’t want to spend too much time on it, but do you have any insight as to the anti-vaccine group, and the idea of the connection of vaccination with a lot of other dreaded diseases? That’s extremely confusing, ’cause now you have two diseases, and some people might think they’re choosing between autism for their child, and measles for their child? That’s a totally falsehood, but where did that come from?

Bonnie Maldonado: Well, I mean, again I think that this has always been true. For example, Ben Franklin did not vaccinate his son against smallpox, and he actually died of smallpox.

Bonnie Maldonado: And that was his one regret. He said, “I have looked back on my life, and the one regret I have is that I did not follow the evidence, and I was not a believer.” Now, of course, hindsight is 20/20.

So I think, again, it comes back to us learning how to communicate effectively. And I think we’ve always been a little bit on a pulpit, our bully pulpit, that we’re right, we’re scientists, we believe in facts.

That’s not enough, we need to convince communities and that’s what we’re trying to do today, in our everyday life, is try and understand what families are worried about. They have so much more access to information that we did as young people, and they all care, obviously, for their children, so when they have to sort that out we have to be able to deliver that message. How do, for example, how do you sell mass marketed products that are bad for you, and get sold, how do we do that we’re clearly the society is able to sell things.

Russ Altman: Right, there are people who are very good at this.

Bonnie Maldonado: Very good at that.

Russ Altman: It’s not necessarily scientists.

Bonnie Maldonado: No, we’re not good at sending our messages out. So, that is an area of research now, which falls into the area of behavioral science, and one of the areas I worked on in the past, and still do too, a bit, is the prevention of mother-to-child transmission of HIV.

I did a lot of the early pioneering work here in the US, in setting up the case definition for pediatric HIV, along with the Centers for Disease Control and others. And then we worked in sub-Saharan Africa, and one of the things that we learned about HIV then is that the best, once we learned about the risk factors for transmission, we thought, well, now we have to try to sell the prevention of this disease by reducing risk.

The biggest predictor of risk reduction is knowing somebody with the disease. So, coming back to this issue of, if you know somebody in your community, if there’s someone in your community who you trust and you know, or god forbid, has that disease, that is the biggest driver of behavior change.

Russ Altman: This is “The Future of Everything,” I’m Russ Altman, I’m speaking with Dr. Bonnie Maldonado, and we’re talking about vaccines, generally, and let’s, I definitely want to get to the HIV work, and I also know you work with polio, but let’s, in the area of measles, that we’ve been learning a lot about the effects of measles on the immune system, through your work, and the work of others. So what have been the new things. You would think that this is an old story, was all solved in the 60s, but there’s actually new things coming out. What’s exciting to you about what we’re learning about measles?

Bonnie Maldonado: Yeah, so, as you said, Russ, we’ve known for many, many years now, decades, that, and some of our early work in measles really tried to elucidate that mechanisms of measles virus. It’s a very complicated virus, in the sense that, it itself, the wild-type measles virus, the natural measles, actually can induce an immunosuppressive state, that is, it suppresses your ability to develop normal immune function and immune response, for several weeks to months.

Russ Altman: OK, so this is not just while you’re sick.

Bonnie Maldonado: This is for the weeks to months, and this was actually especially a problem in the US, when nutrition and health were not as optimal as they are today. But especially in developing settings now, where children and already malnourished, they can actually die from normal health, normal diseases, such as pneumonia and diarrhea, but they’re more likely to die after they’ve had measles disease, and that effect persists for months.

We knew that already, what’s new, what just got published this year, which is very nice, in two science papers that were published, one earlier this year, and one just a few weeks ago, by investigators separately at Harvard and one at MIT, looking at the immune responses before and after getting measles disease, wild-type disease among unvaccinated children. A

nd the data shows that these children actually lose their ability to make antibodies to other diseases, even though paradoxically they eventually may get antibodies to measles, which they caught, and then become immune to.

Russ Altman: Right.

Bonnie Maldonado: It’s at the expense somehow for the immunity to other diseases, so they’ve been able to do these very sophisticated studies with a technique called veer scan, where you can measure thousands and thousands of antibody responses, and they’ve found that children who had wild-type, natural measles disease, and weren’t vaccinated, lost anywhere from 11 to 80 percent of their antibodies to other diseases that they had before.

Russ Altman: Oh, so even if they seen or even been vaccinated, they might lose that resistance.

Bonnie Maldonado: Yes.

Russ Altman: Because of the measles infection.

Bonnie Maldonado: Yes, so they had presence of these antibodies before and they lost them after. Then, the other elegant study that was done by Dr. Petrovka at MIT, recently published a few weeks ago. She actually did very similar work, and she then validated that, and then went back and looked for the immune cell subsets. And she looked at B cells, because we know that T cells are important to abrogate, or to kill measles ultimately, but you need B cells —

Russ Altman: These are the cells that make antibodies.

Bonnie Maldonado: To produce antibodies, so that when you see the measles virus, you will kill it. So, she looked at B cells, in kids who had either severe or mild measles disease. She had those cells typed, and she was able to pull out subsets of the cells, and she found that the cells that were killed, the vast majority, now these were in small numbers of children but in these 20 plus children, she found that the memory cells were the ones that were missing, and about, at least half of the immune cells were gone.

Russ Altman: So these memory cells are the ones that retain the memory of the old exposures, so you can fight them in the future.

Bonnie Maldonado: Yes, so they are cells that, and again they did not characterize what these memory cells responded to.

Russ Altman: What they were remembering.

Bonnie Maldonado: Right, they don’t remember what they were remembering. But these are cells that you produce, when you develop, for example let’s just say you have a, an infected knee, you’ve cut your knee and you develop an infection, your body will make antibodies to whatever bacteria might have infected your leg. And some of those cells will immediately fight the infection, another group of cells is primed to recognize that particular infecting organism, and it will reside in your body for a long time, many years to decades as memory B cells. And those memory B cells, are the ones that are destroyed. 50% of them are gone.

Russ Altman: This is “The Future of Everything,” I’m Russ Altman, I’m speaking with Dr. Bonnie Maldonado, and we’re talking about immunity and memory, and let me just clarify, this is for people who get measles the disease, is there any evidence that the measles vaccine causes any of these problems.

Bonnie Maldonado: That’s a great question, they actually looked at the measles vaccinated children and had none of these responses at all, not one, not a single signal.

Russ Altman: Okay, very important.

Bonnie Maldonado: So very clearly, the measles vaccine not only conferred immunity to measles, but it actually protected your immune system so that it could fight off other infections that you would encounter over your life course. Now the other question of course is, how long does this effect last, and does it change your ability to mount a normal immune response, later on in life.

Russ Altman: Yes and so I think the bottom line is measles is an even worse disease than we thought it was, than we realized. And it has profound, it’s not only causing problems with hearing loss and there can be neurological damage and it’s a terrible disease itself and it might also be increasing the risk for infection by other agents. So just a terrible disease and one that is preventable with vaccination.

I know that you have also done a ton of work with polio and in particular the oral polio virus. This is another disease that we don’t think about in America because hopefully everybody gets their polio vaccine as a kid, and I know I have never seen a case of it as a physician in my practice in Palo Alto, California. What is the state of oral polio and why does it attract your attention?

Bonnie Maldonado: Well it’s interesting, when I first started as a junior faculty member here many years ago, people said, here in the US, “Why are you studying measles “and polio those don’t exist anymore.” And in fact, at the time, measles killed a million children a year in developing settings. And the same can be said for polio in the sense that measles is not a high mortality disease but it cripples children.

Russ Altman: Measles or polio?

Bonnie Maldonado: I’m sorry, polio, polio will cripple children. When I started at Stanford, the World Health Organization had just declared that they wanted to eradicate polio. I worked on viruses, intestinal viruses, and polio is an intestinal virus, so I thought, you know, this would be a very interesting virus to look at, let me understand how, what the approach is around eradication and so I looked at that. Again, as an epidemiologist, I saw that there were some major gaps in our understanding of how this virus really works and how we could best eliminate it.

As we’ve seen, it hasn’t happened very quickly and I think there was some epidemiologic flaws in the way we approached it originally, but I think those are being corrected and some of the work I did was among Mayan children in Southern Mexico as well as in children in sub-Saharan Africa and the idea was to understand how the virus works outside of developed countries.

That is, do you see the same immune responses, do you see the same protection in children who come from lesser developed backgrounds where they might not be as healthy. And the answer is generally no, and so we needed to understand better how do we prevent diseases in these developing settings, so every child can be healthy.

Russ Altman: So can you describe, briefly for us, how does the oral polio virus work? Is it live attenuated, what do all those words mean, what is it?

Bonnie Maldonado: Well so the two vaccines, there were two major vaccines that were invented, and this is really the fabulous story here, is that these were two vaccines that were invented in the 50’s and 60’s that we still use today. They were very good vaccines, we didn’t really understand them well, but they were great vaccines.

One of them was a killed vaccine, that was the first one that was produced by Jonas Salk. And Albert Sabin produced a live vaccine. And the reason that these are important is because a killed vaccine you can inject, as a shot, into somebody and then you develop immunity to that particular virus or organism.

The live vaccine was important because polio is an intestinal virus, it grows in the intestinal tract and you don’t make good immune responses to intestinal organisms in general, you do a better job at making immunity in your blood than you do in your intestinal tract.

Albert Sabin, correctly figured that, if you gave a live virus that looked like polio and in many ways was polio, but had a lot of the bad characteristics, that is the ability to cause paralysis, taken away, we call those attenuated, it’s been modified so that it produces immune responses but you don’t get the disease. So he produced that vaccine. And between the two vaccines, used in the US, in particular, and in Western Europe we were able to really see massive reductions in the number of polio cases in the US over the 50’s, 60’s and 70’s.

Russ Altman: Definitely want to dive into this a little bit deeper in a moment. This is “The Future of Everything,” I’m Russ Altman, more with Dr. Bonnie Maldonado about polio, vaccines, and a little bit about HIV next on Sirus XM.

Welcome back to “The Future of Everything,” I’m Russ Altman. I’m speaking with Dr. Bonnie Maldonado, and we were just talking about oral polio virus. And you were saying it was an intestinal, that the Sabin version is an attenuated virus that lives in the intestine. But it works, first of all, and second of all, this, I think, relates to this idea of herd immunity. And I wonder if you could just take us through what does that mean, herd? I don’t think of myself as a member of a herd but maybe I should.

Bonnie Maldonado: Well we actually, for an epidemiologist, we all are, we’re related, we’re all herds, we’re all big populations.

So polio virus, the live vaccine is great in the sense that, in developing settings in particular, when you take a live oral vaccine and you ingest it. First of all it’s very cheap, super cheap, you can use it anywhere, it’s a couple of drops on the tongue, I’m sorry the back of the throat, you shed that, not only do you develop immunity, you shed that into the environment and given that these are contaminated environments, people will pick up the virus from the environment and become immune themselves.

Russ Altman: Without officially being vaccinated.

Bonnie Maldonado: Yeah, exactly, without getting vaccinated. So the concept of herd immunity is that, is that that’s one way to think about herd immunity. the other is just how many people in a population, whether they’re transmitting disease themselves have been reduced.

For example, if you have a highly contagious disease, like measles, coming back to that, out of 15 people who don’t have immunity to measles, one person with measles can infect 14 of those people. And so, so if you have a room of 15 people and 14 of them are already immune, and not susceptible and then somebody comes in with measles and then you will only have one person infected, instead of 14. So the idea of herd immunity is that you keep your herd healthy if you are yourself immune, by keeping yourself from exposing other people.

Russ Altman: That’s right, and it prevents the spread and can snuff out epidemics before they occur.

Bonnie Maldonado: Yes absolutely.

Russ Altman: So I know that you have also looked, in the case of HIV work, and you mentioned your HIV work earlier, but especially there’s been some progress in helping people with HIV understand the importance of their treatment regimens and their vaccine regimens, what has been learned there.

Bonnie Maldonado: Well so, I think that it’s very applicable to the vaccine area even though we don’t have a vaccine, because what we’ve done in the last 30 plus years is really de-stigmatize HIV so that people were not afraid to come forward, not afraid to listen, not afraid to get involved, and now we have opened programs where counties and cities and states are giving people testing centers and also getting treated and prophylactic treatment, that is preventative treatment so that they don’t get HIV, and 30 years ago nobody wanted to come forward and say they were infected or try to find out.

I found that in sub-Saharan Africa, what really worked for us and has worked in this country as well is getting community involvement. So getting the message to the community is so important because once you get buy in from communities, then they will be the best messengers in their own local areas, I think that’s what we need to try to do with vaccines.

Russ Altman: And it sounds like this is a generalizable set of practices that you might be able to apply even outside HIV. You’ve already applied it outside of the US, so it seems to have legs, as a general strategy.

Bonnie Maldonado: Yes and we’re trying to do that here in the US, too. There are, I am a part of the American Academy of Pediatrics and many other academies as well as the Centers for Disease Control, other government agencies and non-profit organizations who are really trying to engage as community members in this message that we need to protect our children and adults against diseases.

Russ Altman: So relating to that, I know you also have some thoughts and observations about the anti-vaccine community. And it directly relates to this idea of both educating and reaching out. What have your observations been?

Bonnie Maldonado: Well these are my personal anecdotal observations, but actually now a science behind it as well, which it took us a while to get there, but there are now some studies.

And one of the things we found is that this is not one community, people have varying reasons for not wanting to vaccinate themselves or their children. And I think it’s a mistake for us to assume that they all speak with one voice. We really need to personalize, there’s this kind of this personalized medicine approach, find out what a person is really concerned about and what is the community concerned about.

There are very different reasons, for some groups, for example it’s a religious issue, for other groups it’s really a freedom of choice issue, and for others it’s really something about science and maybe not understanding science. So we’ve gotten a better idea of that and really the core group of anti-vaxxers we think is smaller, but there are a number of people who question, and we should be much more accepting of those who question, and try to get to them so that we answer their questions, allay fears and tell them, be very transparent about the information that we have and that we don’t have.

Russ Altman: This is “The Future of Everything,” I’m Russ Altman, I’m speaking with Dr. Bonnie Maldonado, and this very difficult task of convincing people who come into a situation, probably with pretty strongly held beliefs and rather than pushing them away, trying to engage them in conversations. Have there been emerging best practices for how to do that in a non-confrontational, scientifically based way? Or are we just at the very beginning days of that?

Bonnie Maldonado: Well, the good news is that if you ask people in surveys, they still trust their medical provider, and families do trust their medical providers, and so that’s a really good platform to start with. We really try to educate our local physicians on the messaging that we want them to understand around the facts and the science and they really come back to us and tell us how they message and we study those messaging practices to see which ones work best.

Russ Altman: Great and I know this is important because in particular you were involved in a committee, it’s called The Advisory Committee on Immunization Practices. First of all, who are you advising, and tell me about the mission of that committee and the successes or challenges.

Bonnie Maldonado: Yes, so we’ll call it the ACIP for short, but it is a Federal committee, and I am a liaison to that committee. One of my faculty members here at Stanford is actually a voting member of the committee. And that’s an advisory committee, it does not make policy itself, but it does a lot of really in-depth work, there’s a very broad representation of public health experts, academic physicians, community based advocates.

We advise on any vaccine that has come up for approval and licensure by the FDA, and of course not every vaccine is approved by this committee or reviewed by this committee for use, but those that are salient, those that are important for public health are really looked at in depth.

For example, every year this committee works in understanding guidelines for influenza vaccination. And this committee does a great job of engaging community members across the country, in fact this is one of the hallmark committees, I think, in an international setting. How we can be engaging at the community level, through internet-based webinar meetings, these are all free and open to the public, and we engage in the facts of vaccines, we openly debate the risks and benefits of vaccines and we help to make policy recommendations around how vaccines should be used.

Russ Altman: Excellent, and so from your perch as a liaison to that committee, can you tell us about of some of the exciting new things that are coming down the pike, or persistent challenges that frustrate the committee, either one of those, I think, will be of great interest.

Bonnie Maldonado: Right, well the one that’s always both, happy and sad news is influenza, because that is always a very cryptic virus, we don’t understand it very well yet even though we should. But every year we are, the group is, tasked with trying to decide how to communicate influenza effectiveness for the last year and try to predict what’s gonna happen in the next year. So that can be frustrating but it’s also exciting to hear all the news that’s coming.

Russ Altman: It does seem variable, sometimes the public learns that this year’s virus is a particularly good one, and sometimes you hear, “oh we might have to re-do it.” And so I’m sure that causes problems in terms of communication and uptake.

Bonnie Maldonado: Yeah, it does, it is a communications issue but I think what’s really exciting about it is we do get community feedback and people understand. I think a lot of people do understand that we just don’t have that crystal ball yet, so it would be great if some of our colleagues, our immunology colleagues, could help us understand how to predict what’s gonna happen from season to season. We do a reasonably good job overall but we could do a much better job.

Russ Altman: And finally I wanted to make sure that we mention that, even though there have been outbreaks of measles in the United States, I think, my understanding is, that this has come from the outside and that we still consider the US to have eliminated measles as an endemic thing within the US, is that correct?

Bonnie Maldonado: Yes, so in 2000 we were declared having elimination status for measles and we almost lost that designation this year because we had a series of long outbreaks, but fortunately, because people stepped up to the plate, we have overall good vaccination rates, we were able to maintain our elimination status.

Russ Altman: Thank you for listening to “The Future of Everything,” I’m Russ Altman, if you missed any of this episode, listen anytime on demand with the Sirus XM app.


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