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Dr. Yomaris Pena, internal medicine physician with Somos Community Care, extracts the last bit of Pfizer-BioNTech COVID-19 vaccine out of a vial at a vaccination site in New York. (AP) Dr. Yomaris Pena, internal medicine physician with Somos Community Care, extracts the last bit of Pfizer-BioNTech COVID-19 vaccine out of a vial at a vaccination site in New York. (AP)

Dr. Yomaris Pena, internal medicine physician with Somos Community Care, extracts the last bit of Pfizer-BioNTech COVID-19 vaccine out of a vial at a vaccination site in New York. (AP)

Daniel Funke
By Daniel Funke February 26, 2021

The coronavirus vaccine doesn’t cause Alzheimer’s, ALS

If Your Time is short

  • Classen’s paper presents no evidence other than a three-sentence methods section that summarizes an unspecified analysis of the COVID-19 vaccine.

  • Coronavirus vaccines developed by Pfizer-BioNTech and Moderna have not been linked to neurodegenerative or prion diseases.

A research article making the rounds online claims that the COVID-19 vaccine could cause diseases like Alzheimer’s. Don’t believe it.

In the article, published in the journal Microbiology & Infectious Diseases in January, J. Bart Classen wrote that components of the coronavirus vaccines may cause the misfolding of proteins associated with Alzheimer’s and Lou Gehrig’s disease, also known as amyotrophic lateral sclerosis.

"The enclosed finding as well as additional potential risks leads the author to believe that regulatory approval of the RNA based vaccines for SARS-CoV-2 was premature and that the vaccine may cause much more harm than benefit," Classen said in the paper.

The article was surfaced to PolitiFact by VineSight, a firm that tracks online misinformation. It has been shared widely on social media and blogs that advocate against vaccines, so we wanted to take a closer look.

The research article is baseless — there is no evidence that the coronavirus vaccine causes Alzheimer’s, ALS or prion diseases. When we reached out to Classen for a comment, he said his paper "speaks for itself."

Microbiology & Infectious Diseases is hosted by SciVision, a platform for open-access journals that librarian Jeffrey Beall listed as a potential predatory publisher aimed at profiting from academics instead of offering rigorous peer review. Classen has previously published research falsely linking vaccines to diabetes. He speculates on his website that the coronavirus pandemic "is actually a bioweapon attack and may be linked to the U.S. anthrax attack of 2001."

He also included that claim — which PolitiFact has repeatedly debunked — in the body of his research article.

Putting the bogus bioweapon claim aside, let’s take a closer look at Classen’s paper.

Prion diseases are a family of rare neurodegenerative disorders. They’re caused by pathogens called prions, which can cause abnormal folding of proteins most commonly found in the brain. One example is mad cow disease, a brain disorder in cattle that can spread to humans through infected meat.

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The coronavirus vaccines use a new but well-researched technology called mRNA, which tells the body how to produce copies of the protein on the surface of the virus without infecting the patient. In his paper, Classen says mRNA vaccines may trigger the misfolding of proteins associated with Alzheimer’s and ALS, as well as prion diseases.

His evidence? He doesn’t really say. All he includes is a three-sentence methods section summarizing an unspecified analysis of the coronavirus vaccine.

In an article debunking Classen’s paper, the American Council on Science and Health, a nonprofit science advocacy organization, wrote that Classen’s paper lacks evidence and is "entirely speculative."

"How was (the vaccine) analyzed? What software was used? Did he examine any controls, like cellular mRNA sequences? He doesn't say," the organization wrote.

RELATED: Deaths after vaccination don’t prove that COVID-19 vaccine is lethal

The Food and Drug Administration has granted emergency use authorization to two coronavirus vaccines: one from Pfizer-BioNTech and one from Moderna. Clinical trials with tens of thousands of participants indicated no connection between the vaccines and neurological disorders like Alzheimer’s or ALS.

Millions of Americans have received the Pfizer and Moderna vaccines since they were approved. If they caused neurodegenerative or prion diseases, those instances would be documented in the federal government’s Vaccine Adverse Event Reporting System — but they’re not.

"VAERS has received no reports of prion-related diseases, Alzheimer's disease, or amyotrophic lateral sclerosis (ALS) after COVID-19 vaccination," said Martha Sharan, a spokesperson for the Centers for Disease Control and Prevention. "No evidence to date indicates a causative association between COVID-19 vaccines and these conditions."

Classen’s claim is inaccurate and ridiculous. We rate it Pants on Fire!

Our Sources

American Council on Science and Health, "No, COVID MRNA Vaccine Won't Cause Alzheimer's Or Prion Disease," Feb. 19, 2021

American Council on Science and Health, "The Anti-Vaccine Movement Gains Traction, Ignoring The Science," May 15, 2014

Beall’s List of Potential Predatory Journals and Publishers, ​Potential predatory scholarly open‑access publishers

Centers for Disease Control and Prevention, Bovine Spongiform Encephalopathy (BSE), or Mad Cow Disease

Centers for Disease Control and Prevention, COVID-19 Vaccinations in the United States

Centers for Disease Control and Prevention, Prion Diseases

CrowdTangle, accessed Feb. 26, 2021

Email interview with J. Bart Classen, Feb. 26, 2021

Email interview with Martha Sharan, a spokesperson for the Centers for Disease Control and Prevention, Feb. 25, 2021

Food and Drug Administration, COVID-19 Vaccines

Food and Drug Administration, FDA Briefing Document: Moderna COVID-19 Vaccine

Food and Drug Administration, FDA Briefing Document: Pfizer-BioNTech COVID-19 Vaccine

Iowa State University library, "What is a predatory publisher?"

Johns Hopkins Institute for Vaccine Safety, "Do Vaccines Cause Diabetes?"

Microbiology & Infectious Diseases, "COVID-19 RNA Based Vaccines and the Risk of Prion Disease," Jan. 18, 2021

PolitiFact, "Tucker Carlson guest airs debunked conspiracy theory that COVID-19 was created in a lab," Sept. 16, 2020

PolitiFact, "What we know about the source of the coronavirus pandemic," April 17, 2020

PolitiFact, "8 facts and 4 unknowns about the coronavirus vaccines," Dec. 17, 2020

Vaccine Adverse Event Reporting System, accessed Feb. 26, 2021

Scientific American, "Childhood Vaccines Cleared of Autism, Diabetes Link in New Report," Aug. 25, 2011

Vaccines.net, accessed Feb. 25, 2021

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The coronavirus vaccine doesn’t cause Alzheimer’s, ALS

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