RFK Jr. says CDC covered up data that showed a 10-fold increase in autism: is this true?

It is not.

Last week, a clip widely circulated on social media, with current HHS Secretary Robert F. Kennedy Jr. claiming that the hepatitis B vaccine was found to cause a more than 10-fold increase in the rate of autism, with the CDC burying this finding.[1]

RFK Jr. portrayed the agency as malevolently “covering up” the finding to hide its malfeasance and continue pushing vaccines.

This is false.

Now, I have no love for the CDC. During the COVID-19 pandemic, the agency and its leadership coordinated with other agencies, institutions, and the news media to spearhead one of the most catastrophic and criminally incompetent mass “behavioral modification” (read: propaganda) campaigns in the history of public health.

The sheer volume of lies, dissimulation, and gaslighting from the government officials at these agencies and others—many of whom had once given an oath to “do no harm”—remains incomprehensible.

And I am not alone in that opinion. The Atlantic published on this just today:[2]

Suffice to say, when The Citadel publishes on it, it’s now a thoroughly commonplace view. Not much that is new or interesting makes it into the pages of the Atlantic: it is a weathervane for consensus long after consensus has already been established.

But this view wasn’t commonplace when I first wrote about it in Newsweek, the aftermath of which led to the loss of my career.[3]

I will speak truth here, regardless of where that truth lies. The truth is important, regardless of who speaks it and whose agenda it promotes. And, for those for whom this is not obvious, I will explain why in a moment.

RFK Jr.’s claims are simply false. And are frankly so far from the truth that they would make Fauci blush—if he had the shame to blush. (He does not.) Indeed, while Fauci repeatedly lied by narrowly interpreting the scientific evidence, shorn of the context that was widely known to his scientific colleagues (who quietly warned that we were heading toward disaster), RFK Jr. distorts every fact that he comes across, contorting them all to fit his predetermined view.

I will show a sample of this in this post and the ones to follow.

Let us begin.

The "study" being referred to by RFK Jr. was a preliminary analysis by CDC scientists of health records for ~124,000 children conducted in 1999, called the Vaccine Safety Datalink study.[4]

But, contrary to RFK Jr.’s implication, this 1135% increase in the rate of autism figure did NOT come from this study. It came from a spreadsheet containing a preliminary analysis that was being passed around among CDC scientists, who were discussing how to properly analyze the data for the study.

This figure was obtained by an organization named SafeMinds through FOIA. SafeMinds submitted a FOIA that asked the CDC for the emails and the attached spreadsheets, and they found this 1135% figure in one of the spreadsheets.[5]

This is important, as we shall see in a moment.

The study that this analysis was conducted for came to be known as Phase 1 of the Vaccine Safety Datalink study. Phase 1 of VSD was a data-mining exercise. Investigators ran hundreds of statistical tests under varying assumptions. The goal was to look for any possible signal that they could find. They were trying to find a safety signal, because they wanted to make sure the vaccine was safe. Hunting for a safety signal by any means possible is how you do this. This 1135% figure was the outcome of one of those tests.

It is important to understand that when you run hundreds of statistical tests even on pure noise, some tests will come up positive and others will come up negative.

To demonstrate this, here are some plots from the early screen, from a slide deck from SafeMinds:[5]

These figures pose a crucial question that illustrates the point.

Why do some brain disorders statistically increase in vaccinated children, while others statistically decline?

In other words, if the vaccine is harming the brain in some ways, why is it also helping the brain in others?

This is what the CDC scientists asked themselves.

But then the researchers asked themselves another question.

Could this noisy dataset that had been tested hundreds of times for associations have simply produced spurious associations by chance, in both directions?

It's worth pausing for a moment here to ask ourselves another question: why did RFK Jr. only focus on the autism finding in this preliminary analysis?

Why didn't he mention the lower risk of cerebral palsy, coordination problems, other developmental delays?

Because these signals were equally present as the autism signal. So why only focus on one of them?

Conceivably, this could have actually been a story about how the CDC buried the positive effects of vaccines.

But back to our story.

Something that bothered the scientists: some of these signals were highly statistically significant. This means that it is less likely that these results resulted purely from applying a bunch of tests.

So that couldn't be the only explanation.

So they started digging deeper into the data and found a number of inconsistencies:

a. The unvaccinated children were very different from the vaccinated children and many rarely visited the doctor, so they were much less likely to be diagnosed with ANYTHING.

b. The coding between the clinics was highly inconsistent, skewing the data.

c. There were only 2,500 unvaccinated children, out of more than 100,000 total. Given this tiny sample, tiny changes in the incidence of any diagnosis in this group could have large effects on the differences in diagnoses, if this sample was used as the reference against which to compare the other groups.

And they found a number of other ways that the data was broken and biased.[4,6]

For example, there were only 13 cases of autism among more than 100K children and only 2500 unvaccinated children. This means that by chance there were unlikely to be any unvaccinated children with autism. It may be the case that 0.5 was the count of unvaxed children with autism in the prelim analysis (because the real number was 0), due to default settings in SAS at the time, to avoid a denominator with zero.[4]

So the scientists ran what is called sensitivity analyses: variables like which codes were used or which birth year or whether you got the vaccine at one clinic or the other down the street shouldn't impact the findings. And so on.

And the researchers found that the results were highly sensitive to these kinds of variables, which suggested that these variables were skewing the data.[4]

To be clear, the question wasn't whether if you went to clinic B in Boston or clinic A--would that affect your rate of brain disorders. The question was whether getting a vaccine would. So they tested to see if their results were robust to these kinds of irrelevant differences.

And they weren't. The entire analysis fell apart when extraneous variables like these were accounted for.

In epidemiology, this means that the analysis simply isn't robust: if irrelevant variables can have a major impact, it means that your data are introducing biases that you are not adequately controlling for and/or do not understand.

Once these chance variables were adjusted for, most of the significant findings disappeared in both directions. The reductions in brain disorders fell to nearly 0, and so did the increases.

Once they made these adjustments, they convened a meeting with dozens of top experts in the world who did not work at CDC, discussing all of the above. These experts were convened to provide outside opinions, from outside scientists. The CDC scientists were looking for feedback and dissenting opinions.

This was called the Simpsonwood Workshop, and a full transcript of its proceedings was immediately published by the CDC, as well as the findings, made available to the public.[6]

The transcript is 259 pages and anyone can read it today to see what these scientists had discussed. They discussed everything I have just mentioned above.[6]

Now, to give some more relevant context, the issue being discussed with the hepatitis vaccine was whether the thimerosal was causing neurotoxicity. There was some concern from the literature on mercury toxicology literature that thimerosal (ethyl-mercury) could be neurotoxic.

Given that context, most attendees endorsed the goal of eliminating mercury from pediatric vaccines "as soon as feasible", out of an abundance of caution.[6,7] Meanwhile, the participants still believed that the data that the CDC scientists presented was "interesting but too fragile".

It was, basically, a bunch of scientists who generally favored eliminating thimerosal out of an abundance of caution but who did not think that these findings were very compelling.

This is what RFK Jr. does not talk about. To call this a cover-up is an insult to proper cover-ups. It was all out in the open. It exemplified the kind of open science that would be almost unthinkable today.

These findings were then published, showing a modest increase in tics (nearly 2x) and speech delay (about 10%).[4]

A follow-up study was then planned. This time, the protocol was circulated for comments. This wasn't an exploratory analysis like last time. They knew exactly how they wanted to conduct the study to control for the messy data, so there could be no question of tinkering with variables. And they collected a completely new batch of data, including from clinics that hadn’t been included in the original study.

The study, VSD Phase 2, was then published, which failed to show any impact on tics, speech delay, or autism.[4]

Let's be clear. The unvaccinated group was NOT made the reference group in these studies for the reasons I have described above. It was too noisy, and the unvaccinated group simply was completely unlike the vaccinated group.

Instead, the low-thimerosal group was compared to the high-thimerosal group. And nothing could be found.

This wasn't to hide anything, but because of intrinsic flaws in the data.

And get this:

Later work years later confirmed that thimerosal blood levels acutely rose to less than 10% of the levels required to produce neurodevelopmental effects if a baby is exposed for a ~year.[8]

And the exposure of babies to this ~10% level from thimerosal? They were exposed for just hours to days, compared to the months of chronic methylmercury exposure (from high fish consumption in pregnant women) required to see small IQ effects at more than 10x the level.[8-12]

In other words, this work later confirmed that the removal of thimerosal was almost certainly precautionary. But regulators were vigilant and removed the offending chemical anyway, and were doing so long before this study was conducted.[7,8]

So, I ask again: where was the cover-up exactly?

Allow me to make an additional meta-point.

Elsewhere, RFK Jr. insists that only RCTs can provide valid evidence of vaccine risk profile. Now this is completely untrue: in fact, observational studies are often dramatically superior to RCTs in this regard. But suddenly, throwing out that position completely, in this case a preliminary analysis with definitive evidence of residual confounding becomes some dispositive signal of vaccine harms and insisting on proper covariate adjustment is an indication of some kind of dramatic autism "coverup".

Does RFK Jr. ever listen to his own words, to the obvious contradiction here and the obvious motivated reasoning and double standards in his own statements?

Again, I get that people are upset about COVID-19. I got pericarditis from the COVID vaccine. I was afraid I would die. I thought it was a conspiracy theory that the COVID vaccine caused pericarditis, even after I got it. It wasn't. We were lied to during the pandemic. A hysterical ideology took hold of our public health establishment. They politicized the pandemic, and they lied to the public relentlessly.

When I came to understand this, I wrote about it extensively, first in Newsweek, and then on this platform. I wrote bangers on X, and I was viral. My medical school didn't like it, and there was a massive cancelation campaign launched on that platform. A flood of emails and notified the school of my Wrong Think. I was betrayed by almost every single person closest to me, in ways that are almost impossible to describe (but which I will, soon). The physicians at my school participated in the way they knew best, with relentless bullying, harassment, and fake evaluations. I was dismissed.

Despite recommendations from some of this country’s most influential physicians and scientists—those who now populate the upper ranks at HHS beneath Kennedy all know who I am, some well—I will never return to a profession that can treat a person like that. I will not live in fear of that happening. I will never see the profession the same away again.

I wrote what I did because I care about the truth, because I have dedicated my life to scientific truth, and the public health establishment spread a hysteria at the expense of truth.

So allow me to suggest that we should reverse the narrative.

What's really important here?

The reason the public health establishment botched the pandemic response is that they claimed to speak in the name of science when they didn't.

They spoke in the name of fear at the expense of science.

They got school closures wrong, masks wrong, vaccines wrong, lockdowns wrong. It was a disaster of monumental proportions, because they called certain claims scientific that weren’t, and they used fear to compel conformity to their lies.

So let me end this with a question:

How is what RFK Jr. doing any different from what Fauci did, just in the opposite direction?

He's creating hysteria and calling it science, at the expense of science.

That's what Fauci did.

That's what the entire public health establishment did.

There are different players now they're doing it again. Right now.

I paid the price with my med school dismissal. I didn't sacrifice my medical career for nothing.

Public health deserves more. Medicine and public health are all that I am, and I will fight for what they represent and could and should be. Today, corruption is endemic. I won’t abet it with my silence. If I do, then everything I gave up will mean nothing.

I will explain more in other posts about RFK Jr. soon.

Then as now: I will not comply.

While others take sides, I will fight for science, as I always have.

The truth is the only chance our species has.

Bibliography

[1] ABC News. "RFK Jr., CDC panel have been casting doubt on the hepatitis B vaccine." Published July 3, 2025. https://abcnews.go.com/Health/rfk-jr-cdc-panel-casting-doubt-hepatitis-vaccine/story?id=123423585

[2] The Atlantic. "How Public Health Discredited Itself." Published July 7, 2025. https://www.theatlantic.com/ideas/archive/2025/07/public-health-politicization/683409/

[3] Newsweek. "It's Time for the Scientific Community to Admit We Were Wrong About COVID and It Cost Lives." By Kevin Bass. Published January 30, 2023. https://www.newsweek.com/its-time-scientific-community-admit-we-were-wrong-about-coivd-it-cost-lives-opinion-1776630

[4] Verstraeten T, Davis RL, DeStefano F, et al. "Safety of thimerosal-containing vaccines: a two-phased study of computerized health maintenance organization databases." Pediatrics. 2003;112(5):1039-1048. https://publications.aap.org/pediatrics/article/112/5/1039/28714/Safety-of-Thimerosal-Containing-Vaccines-A-Two

[5] SafeMinds. "Generation Zero: Preliminary Analysis of VSD Data on Thimerosal (PowerPoint Slide Deck from FOIA Materials)." Accessed via SafeMinds archive. https://www.safeminds.org/wp-content/uploads/2014/04/GenerationZeroPowerPoint.pdf (Related FOIA request details: https://www.safeminds.org/wp-content/uploads/2014/02/SafeMinds-CDC-FOIA-request-Nov-13-2000.pdf)

[6] Centers for Disease Control and Prevention (CDC). "Scientific Review of Vaccine Safety Datalink Information (Simpsonwood Transcript)." June 7-8, 2000. https://www.safeminds.org/wp-content/uploads/2014/03/simpsonwood-transcript-scientific-review-of-vaccine-safety-datalink-information.pdf

[7] Centers for Disease Control and Prevention (CDC). "Thimerosal and Vaccines." Last reviewed 2023 (with updates on precautionary removal). https://www.cdc.gov/vaccine-safety/about/thimerosal.html

[8] Burbacher TM, Shen DD, Liberato N, et al. "Comparison of Blood and Brain Mercury Levels in Infant Monkeys Exposed to Methylmercury or Vaccines Containing Thimerosal." Environmental Health Perspectives. 2005;113(8):1015-1021. https://pmc.ncbi.nlm.nih.gov/articles/PMC1280342/

[9] Grandjean P, Weihe P, White RF, et al. "Cognitive deficit in 7-year-old children with prenatal exposure to methylmercury." Neurotoxicology and Teratology. 1997;19(6):417-428. https://www.sciencedirect.com/science/article/abs/pii/S0892036297000974

[10] Davidson PW, Myers GJ, Cox C, et al. "Effects of prenatal and postnatal methylmercury exposure from fish consumption on neurodevelopment: outcomes at 66 months of age in the Seychelles Child Development Study." JAMA. 1998;280(8):701-707. https://jamanetwork.com/journals/jama/fullarticle/187942

[11] U.S. Environmental Protection Agency. "Methylmercury (MeHg) (CASRN 22967-92-6)." Integrated Risk Information System (IRIS). 2001. https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=73

[12] Institute of Medicine (IOM). "Immunization Safety Review: Vaccines and Autism." Washington, DC: The National Academies Press; 2004. https://www.ncbi.nlm.nih.gov/books/NBK25349/