The following is the full transcript of an interview with Dr. Peter Marks, former head of FDA’s Center for Biologics Evaluation and Research, a portion of which aired on “Face the Nation with Margaret Brennan” on April 13, 2025.
MARGARET BRENNAN: We are joined by Dr. Peter Marks, who recently resigned as the FDA’s top vaccine regulator. Welcome to Face the Nation.
DR. PETER MARKS: Thanks so much for having me today.
MARGARET BRENNAN: I want to talk to you about a number of things, but let’s talk about one of the most immediate problems, and that is this measles outbreak. The CDC has now recommended additional measles shots for people traveling within the U.S., specifically to the states of Kansas and Texas due to record outbreaks. The guidance wasn’t on the website, but it was told to local authorities, what do you make of that public health guidance?
DR. MARKS: What I make of that is that we have enough spread of measles and some uncertainty in people’s vaccination status that they’re trying to make sure that people are as protected as they can be. Some people who were vaccinated, for instance, for a period in the early 60s, they may not be fully vaccinated in the extent that the vaccine was not as good back then. So sometimes we ask them to get revaccinated and additionally, some people don’t know their vaccination status. So better to be safe than to put yourself at risk, because it is a very- it’s one of the safer vaccines that we have. In fact, it is possibly characterized as among the safest vaccines that we have.
MARGARET BRENNAN: The MMR vaccine.
DR. MARKS: The MMR vaccine.
MARGARET BRENNAN: So you just said something interesting. You said the- the composition of the shot was different years ago, the quality of it?
DR. MARKS: It- it was- right, well, it was the quality of the shot that was being given, the potency, that’s the strength of it. For a period of time for a few years in the early 60s was such that there are generally people in the period between about 1957 and 1967 if they got vaccinated against measles, they may want to ask their doctor if they should be revaccinated.
MARGARET BRENNAN: Okay, I focus in on that, because the HHS Secretary said that the measles vaccine quote “wanes,” that was the word he used in effectiveness 4.5 percent each year, and that older people are essentially unvaccinated and unprotected. That’s slightly different from what you’re saying. Is what he characterized correct, because it does sound like you’re saying older Americans might want to look into this.
DR. MARKS: Older Americans- so first of all, if you were born before 1957 it’s unlikely that you have to worry about this, because you almost certainly had the measles like I did. I wasn’t born before 1957 but I had the measles just the same, okay. But if you were born before 1957 we don’t worry about measles vaccination because it’s assumed that people had the measles, and natural measles infection gives one pretty robust lifetime immunity. There’s a period between 1957, 1967 some people say 1963, but to be generous we’ll say 1967, when if you got the measles vaccine, you might want to check with your doctor. And then, since that time, though, the newer version of the measles vaccine, as long as you’ve had two doses of that vaccine, it’s generally considered to provide lifetime protection, and we don’t generally see people later in life getting measles. I mean, it’s true, there are people who have immunocompromising conditions that may need to be revaccinated later in life. But in general, if you’ve had two doses of the measles vaccine, one doesn’t need to get revaccinated.
MARGARET BRENNAN: Two doses, it’s not wearing off is what you’re saying.
DR. MARKS: It’s- well–
MARGARET BRENNAN: It’s not waning?
DR. MARKS: It’s- it’s not- so let’s- let’s be clear, many vaccines, the protection wanes over time, but there’s a threshold effect, and as long as you’re above that threshold in terms of protection, you’re safe. And so by and large, when people have had two doses of the existing MMR vaccine that’s used in the United States, they maintain, for all intents and purposes, lifetime immunity against measles.
MARGARET BRENNAN: Secretary Kennedy spoke to my colleague, Dr. Jon LaPook earlier this week, following the death of a second unvaccinated child in Texas due to measles. Kennedy reiterated people should get the MMR vaccine. Take a listen.
(TAKE VIDEO)
DR. JON LAPOOK: What’s the position philosophically of the federal government in terms of public health?
HHS SECRETARY ROBERT F. KENNEDY JR.: The federal Government’s position, my position is, people should get the measles vaccine, but if- the government should not be mandating those–
DR. JON LAPOOK: Understand, but the–
HHS SECRETARY ROBERT F. KENNEDY JR.: – I always said during my campaign and in every part, every public statement I’ve made: I’m not gonna take people’s vaccines away from them. What I’m gonna do is make sure that we have good science so that people can make an informed choice.
(END VIDEO)
MARGARET BRENNAN: Is that a sufficient endorsement?
DR. MARKS: So I’m not going to comment to that, but I’m going to tell you as a public health professional. I’m going to tell you what an endorsement of the measles vaccine sounds like right now. If you can hear my voice right now, and you have a child that is unvaccinated against measles, we have measles spreading in this country very significantly. You wouldn’t put your child in a back seat of a car without being strapped into their car seat. You want to get your child vaccinated against measles so that they don’t have a one in a thousand chance of dying from measles if they contract it. There’s no reason to put your child at that risk, because the vaccine does not cause death, it does not cause encephalitis and it does not cause autism. So a vaccine that is safe, yes, occasionally kids get fevers. If you don’t keep the fevers down, about 15 in 100,000 will get a convulsion that happens once it goes away. But if you take their temperatures, keep it down, that’s unlikely. And the other four or five side effects per 100,000 are ones that come and go. So, very safe vaccine that is going to potentially protect your child and save its life. And there’s just- the issue here is we should love our children enough that if you care about your child, just like you’d strap them in that car seat, you’re going to get them vaccinated with two doses of the measles vaccine. They will be well protected against this. Once you’ve had two doses of the measles vaccine, it’s virtually unheard of that a child dies of measles. Three or four percent may get the measles, but it’s not a life threatening illness, so it’s really important to get vaccinated. Get your child vaccinated if you need to, you have questions, ask your pediatrician, ask your health care provider. If you have religious objections or issues, go to your clergy member, because most major religions actually understand how important vaccination is, and they will go ahead and tell you that it’s okay to get vaccinated. So that’s what an endorsement sounds like. Just make the comparison.
MARGARET BRENNAN: That has to be extremely frustrating for you. As someone who worked in the vaccine space for so long, you clearly feel that this is safe and effective, and that not saying it clearly is endangering people
DR. MARKS: Yeah
MARGARET BRENNAN: Am I understanding–
DR. MARKS: So another way. Yes, No, exactly–
MARGARET BRENNAN: Your frustration?
DR. MARKS: Exactly. But there’s a whole host of people who can’t speak out like I am that are saying, you know, this is a vaccine for which the benefits so greatly outweigh the risks that to not use it is the equivalent of, again, throwing- I mean, if you saw a child, if you saw a 15-month-old rolling around in the backseat of a car, you’d probably call Child Protective Services. Now, I’m not saying we should have, we should order parents to do this, because I don’t want to get into the whole issue of mandates, but we should have a moral responsibility to protect our children against something that could potentially be life threatening, particularly when it’s spreading across the United States the way it is. Just this week, we now have additional states that have been declared as outbreak states. That means they have at least three cases of measles in them. There are now seven states, the epicenter being obviously Texas, but now Indiana has an outbreak. Ohio has an outbreak. So you can see these are places that are very concerning, particularly because Ohio, Pennsylvania, these are states that have Amish populations, that typically have vaccination rates that are can be as low as in the low 20% range.
MARGARET BRENNAN: You said there are people like you who can’t speak freely. You can speak freely because you’re no longer at the FDA.
DR. MARKS: Correct.
MARGARET BRENNAN: You’re saying your former colleagues can’t directly answer a question. They can’t honestly answer a question and endorse a vaccine, right now?
DR. MARKS: I think it’s challenging in this environment for some of them, but you’d have to ask them directly.
MARGARET BRENNAN: Yeah, in your resignation letter, you wrote of the measles outbreak, and what happens when confidence in science is undermined. You said it’s clear truth and transparency are not desired by the Secretary, but rather he wishes subservient confirmation of his misinformation and lies. Did you ever speak to him about your concerns?
DR. MARKS: So just a matter of record, I never interacted with the secretary. I don’t, I don’t intend to engage on, you know, disputing any of that.its administration can have me come and go. That’s fine. The more important thing here is that we deal with the issue at hand, which is vaccine confidence is really important for this country, and it’s been undermined over and over again over the past years, and now we’re seeing the result of this. By the way, it’s not just measles. We had two deaths in Louisiana from whooping cough, which is caused by pertussis. Again, these are deaths that in under vaccinated or unvaccinated populations, we don’t need to be seeing. And I don’t buy the idea that we need to take a break from infectious diseases to deal with chronic diseases. We can do both. We are a great nation, and we should be able to do both.
MARGARET BRENNAN: That is the current stated policy of the secretary. What you just said, looking more at chronic.
DR. MARKS: You’ll have to say whether it is or not. I can just tell you that, from my perspective, I think we have a broad enough public health enterprise to do both.
MARGARET BRENNAN: But what you seem to be saying there, and I think it gets to the core of what scientists do is you’re dealing in fact, and you are constantly questioning the evolution of the science and adjusting conclusions you need to be able to take in information. You are saying here that the man running HHS doesn’t take in information, wishes subservient confirmation of misinformation and lies. There’s presumed outcomes, is what you’re saying.
DR. MARKS: I think that my words then spoke for itself. I don’t need to belabor it here. You know, science is the pursuit of objective truth for the benefit of mankind and those of us who believe in it, we we take it very seriously, and it hurts us deeply when there are those who would undercut the name of science, undercut the very name of science, because It’s convenient for them to purvey lies. And that’s just, it’s not okay, because at the end of the day, I was so strongly affected by what happened last week with the death of a second child that I actually, actually used profanity with a reporter without while I was on the record without realizing it, which is something I’ve never done. I just- people who know me know that just I try to avoid it, and it just showed me how badly I was affected. Because even one death, even a single death in this country from measles, it’s just it’s not excusable. It’s not, and a second death. And I really, I don’t believe that we should be saying, well, these are people who believe that they shouldn’t be vaccinated. Because my experience–
MARGARET BRENNAN: –The Mennonite community.
DR. MARKS: The Mennonite community. My experience is that if you meet people on their level, they generally will eventually come around. Because in generally, in every religious community, you eventually find someone who understands that part of that religious belief is that you don’t harm those who can’t help themselves. We are as adults, can take care of our children. And I think I don’t have any problem of working on the faith level with people and telling them, look, you know, if you- let me try to answer all your medical questions, and if you’re still left with faith issues that you know that you feel like God will provide for your child. Well, guess what, God provided me. I know about science. Science has provided us with these vaccines that can save your child’s life. God helps those who help themselves. So we have to, we have to communicate better. I’m not- I’m the first to acknowledge that over the course of the past years, particularly during the COVID 19 pandemic, we could have communicated better as scientists. So you’re not going to get any arguments with- from me on that. But right now, with this crisis, there is no reason why we should not as a country be making a full court press to get our measles vaccination rates above 90%, because otherwise we’re not going to get this under control. And for those who can’t, for those who really don’t care about little babies dying or children dying, I’ll tell you what will happen too, once we lose measles elimination status, we will then be forced, potentially, when we go overseas, to places in Europe which have achieved elimination status, we’ll have to show little yellow cards showing that we have either immunity or been vaccinated against measles.
MARGARET BRENNAN: –Those little vaccination passports–
DR. MARKS: Right, those little passports yeah. Now, but, but, I mean, I’m, I’m embarrassed to even use that as a reason, because I couldn’t care less. What I really care about is the fact that along the way of getting there, we will have more deaths.
MARGARET BRENNAN: I appreciate everything you’re laying out there. I want to talk to you about some of what happened during COVID as well, but to follow up on- particularly the MMR vaccine. You know where I’m going next, the allegations of that specific vaccine and links to autism. Many parents probably know ASD diagnosis rates are on the increase in this country. The CDC says the current numbers are one in 36 American children. This is a huge- very broad spectrum of neurodevelopmental disorders. There’s no established cause, but yesterday- on Thursday, the HHS Secretary, Kennedy, said he’s got hundreds of scientists from around the world working on it, and he promised this.
(TAKE VIDEO)
HHS SECRETARY ROBERT F. KENNEDY JR.: By September, we will know what has caused the autism epidemic, and we’ll be- we’ll be able to eliminate those exposures.
(END VIDEO)
MARGARET BRENNAN: That gives tremendous hope to a lot of people. Do you know anything about that ongoing research?
DR. MARKS: I know a minimal amount of effort that’s being going on to try to relook at prior autism research, but I’m not aware of what is being discussed there. And I would just say the following- so I’m somebody who in my career as a physician taking care of patients- and there are people probably who are hearing me now who know that I cared for leukemia patients for a significant number of years. Giving people false hope is something you should never do. It is absolutely- you can be incredibly supportive of people, but giving them false hope is wrong–
MARGARET BRENNAN: –Can you–
DR. MARKS: Unless someone- unless somebody actually knows the answer or has a pretty good idea of the answer right now, or thinks they have a good idea of the answer, I don’t see how one could have- as a scientist, I’m not speaking about anything. If you just ask me, as a scientist, is it possible to get the answer that quickly? I don’t see any possible way. And remember, you’re talking to the person who came up with Operation Warp Speed for vaccines. Autism is an incredibly complicated issue, so we have the issue of diagnosis bias. We don’t know how many of those cases are true- how much of this is true growth of autism, how much of this is just that we now have diagnostic criteria and we diagnose it more often.
MARGARET BRENNAN: You’re saying- just to be clear here, because you hear Secretary Kennedy often compare rates now to when he was a child. What you are saying is that the broad array of things under that ASD umbrella has only widened, so it was a much narrower category than what it is now.
DR. MARKS: Right. And I’m not denying that there could be environmental- and we know there are probably genetic features, there have been publications in scientific journals. There are genetic and environmental possibilities here, but the totality of all these interactions and sorting out this incredible complexity, to try to do that in six months time- my calculation of how many months it is till September, I don’t- you can help do that, but six months time–
MARGARET BRENNAN: Unless you’re buying research from somebody else who’s already in the midst of it?
DR. MARKS: Yes.
MARGARET BRENNAN: I mean, is that credible way to come to a conclusion?
DR. MARKS: He may be aware of a bunch of research that I’m not aware of, and that’s why I’m going to be respectful here. I’d love- you know something? I just- I’d love to hear it presented. But the piece, though, that I will put to- put to you that I will not accept as a cause of autism is the MMR vaccine- or, for that matter, any of the other vaccines we use because we’ve studied them in so many millions of children.
MARGARET BRENNAN: We’re going to- I want to come up to you specifically on this issue, because the President the United States said something artificial is causing autism rates to go up on Thursday, he said, maybe you stop taking something, you stop eating something, or maybe it’s a shot, but something’s causing it. Right after that, RFK appeared- the HHS Secretary, appeared on Fox News and dismissed 14 studies that have shown no link between autism and vaccines. He said it is an epidemic.
(TAKE VIDEO)
HHS SECRETARY ROBERT F. KENNEDY JR.: Epidemics are not caused by genes. Genes can provide a vulnerability, but you need an environmental toxin. So we know that it is an environmental toxin that is causing this cataclysm, and we are going to identify it.
(END VIDEO)
MARGARET BRENNAN: Is there scientific evidence ruling out genetics as a cause of ASD?
DR. MARKS: There’s no- there’s no scientific evidence ruling out genetics. In fact, there’s data that have been published that say that genetics may contribute to autism. There are obviously data that can- that suggest that perhaps environmental factors may, but one has to be incredibly careful- incredibly careful about making associations between environmental factors and autism. There’s a wonderful graphic that shows that Coca-Cola increase goes along with the increase in autism. But there’s also a wonderful graphic that you can find online that shows that the increase in spending on organic food also goes along with the rise in autism. False causality. Scientists do not want to find false causality. We want to find true causality. And maybe, let’s say this- those of us who- many of the people at FDA are like me, we’ve spent six years- I spent six years after getting a college degree, getting an MD and a PhD. I spent six years after that training in internal medicine and getting- doing a fellowship in in hematology oncology so that I have three board certifications. After that, I worked in academic medicine, in industry and in government on really focusing on human health. We have a pretty good sense of science. And so the question is, I hope that people, at least when they’re listening me today, find me a credible witness to say that if I’m telling you that- you know it’s hard to trust people that you see on TV, but if you’re hearing my voice, I hope I’m a credible witness in support of the science behind the benefit and risk- particularly for the MMR vaccine, but it’s true for vaccines in general.
MARGARET BRENNAN: You said there may be environmental factors, environmental toxins. He said, “We know it is an environmental toxin.” How can you know it if the study is ongoing?
DR. MARKS: I’m not going to engage again with Mr. Kennedy on this, but I’m going to tell you how science works. Science, when it’s done as it- at its best, is keeping an open mind to all the possibilities. I don’t know about this, with a large number of cases we have, for sure what causes- and that’s because I’m not an expert in autism. And at least the people I talk to are also wondering and and trying to look at all the different possibilities of environmental, genetic, and it could be one or the other or interactions, but I don’t think anybody has that knowledge that they can speak dispositively like that. People who don’t know science, people who don’t know how science works, people who want to control other people by pseudoscience – they talk in absolute terms. But you will- the way you detect a true scientist from a pseudo scientist is because it’s very rare for scientists to speak in absolutes. There are some absolutes. If I take this mug and drop it now, I know that gravity is going to make it fall to the ground, and it’s going to probably break and make a mess in the studio. On the other hand, most things are not that black and white, and we don’t speak in absolutes. Whereas pseudoscientists find it very easy to speak in absolutes because they’re not actually looking to use science for the benefit of mankind, they’re usually using science for their own benefit.
MARGARET BRENNAN: You spoke about credentials, it stood out to us that Secretary Kennedy has hired someone named David Geier to conduct analysis of the links between autism and vaccines. He was charged by the state of Maryland in 2011 with practicing medicine without a license. That was weeks after his father’s medical license was suspended for putting autistic children at risk by giving them a hormone blocking agent. So what should the public know or expect from the work that he will do for the U.S. government?
DR. MARKS: So all I can say is I would not concede- he’s to the best of my knowledge, he’s not had any training after college in any of the sciences that we value here. What I think we can expect is the expected: that there will be an association determined between vaccines and autism, because it’s already been determined. This is not how science is conducted.
MARGARET BRENNAN: You’re saying there’s a preconceived notion he’s going into the study with is what you’re saying.
DR. MARKS: I know the body of evidence that his- his father, who recently passed away, and I know what Mr. Geier has written in the past, that they have a firm and fixed notion that vaccines cause autism. So it’s very hard for me to see how we’re going to get to any other idea than vaccines cause autism.
MARGARET BRENNAN: Well, we’ll watch for the outcome of his research, but it could have impact, clearly, on vaccines, and uptake of them or faith in them.
DR. MARKS: Yeah. So I just I- I- I think, as someone who believes in the strength of our country, our strength is that we remain healthy as a nation. And we will be less healthy as a nation if we don’t take advantage of vaccines, and our adversaries will laugh at us, because I sincerely doubt that countries like China will actually sit around and- and think that, you know, oh, we should have doubt about measles vaccine. They know that measles vaccine works, and they’re going to have their populations vaccinated. I would also say to you one other thing, while I have a moment on measles.
MARGARET BRENNAN: Sure.
DR. MARKS: To compare our numbers of measles cases to the WHO Europe region, which includes Romania, Uzbekistan, Kazakhstan, other places that have less robust public health efforts than we do, is just- that’s just not the right thing to do. We should be comparing our measles response now to what we accomplished during the first two decades of the 20th century, until the 2019 measles outbreak, which is, we shouldn’t be having any deaths from measles. We shouldn’t be- I have had this problem with several individuals–and this is the closest you’ll get me to a statement that may be a little bit out there–to dismiss children’s deaths due to infectious diseases that are preventable by vaccines as just expected or not a big deal, that’s just not acceptable to me. I’ve watched in my life close family members, two children who have died of parents- those parents were broken. They were broken for years, and it’s bringing tears to my eyes right now. No family should have to lose a child. Even- I- I feel for the families in Texas, even those that feel that they did the right thing by not giving their child the measles vaccine because God wanted it, I feel for them, because they needlessly lost a child.
MARGARET BRENNAN: There are more vaccines your colleagues at the FDA are still working on. I want to ask you about the Novavax COVID vaccine approval. It was delayed. Do you know of any reason why the FDA shouldn’t be approving this COVID vaccine?
DR. MARKS: So I really can’t speak about matters that are still under- under consideration by the agency that I was involved in, but I would say that the fact that we haven’t heard anything about it- because normally, by the goal date for these we’re supposed to hear about them, it’s concerning.
MARGARET BRENNAN: Concerning to you because you think there may be a change in our government’s approach to vaccine approval going forward?
DR. MARKS: I guess on a larger scale, stepping back from any particular vaccine. I think just the fact that I was let go is a concern to me. I think- I hope that it wasn’t because of my work on cell tissue gene therapies and on modernizing the blood donation policies that someone thought I did something wrong. I suspect–
MARGARET BRENNAN: Why would they think that?
DR. MARKS: I don’t know, I don’t know, but I suspect it was because we wanted to- there was a distinct change in how the approach to vaccines would be. And I- I understand that it’s a- it’s a choice, potentially, that we want to focus more on chronic diseases today. But this is like, you know, why would you- why would you de-emphasize something that is so basic to public health? It’s like me telling you, you know, don’t bother anymore separating where you get your drinking water from, from where you put your sewage. You would never do that, right? Because that’s going back 300 years when it was figured out that you shouldn’t do- do that. Why would we go back to putting our children at risk? Remember that- remember that in the- in the 18th century, in places around the globe, 10% of people- 10% of people, died of smallpox because they got it at some point in their life. There were populations where it was 5%, populations 20%. We don’t know what smallpox is anymore. Why? Because of vaccines. And anyone who tries to tell you that it was public health or sanitation or the virus just got tired out, all they need to do is- is look at how robust that virus is to know that the only reason why it’s not here is because of vaccines.
MARGARET BRENNAN: There have been massive personnel cuts to many federal agencies, particularly in the public health space. It’s about 10,000, I believe more than 3,000 at the FDA itself. What does the public need to know about the impact of those cuts?
DR. MARKS: It’s- I think what I can comment on is that the people that are left behind are going to do their best to maintain the public health, okay? They’re struggling because there’s a lot to be done. But they are heroes. I- you know, the people who are the heroes in public health are the everyday people who come in every day. They keep tabs on the infections. They make sure that the vaccines that are coming in for approvals might- work their way through. They make sure that outbreaks are investigated. Those people are continuing to do their job the best they possibly can. And it’s my hope that, you know, things organize appropriately.
MARGARET BRENNAN: Dr. Peter Marks, thank you for your time.
DR. MARKS: Thanks so much.
MARGARET BRENNAN: We’ll be back in a moment.
