Why are mRNA vaccines an unlikely cause of any neurodegenerative diseases?
Why are mRNA vaccines an unlikely cause of any neurodegenerative diseases?
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February 3, 2022: A small amount of new data has emerged that suggests a possible association between COVID-19 vaccines and a slight increase in risk of certain neurodegenerative diseases. An October 2021 study found that there was a slight increase in neurodegenerative conditions Guillain–Barré syndrome and Bell's Palsy after the Pfizer-BioNTech vaccine and the AstraZeneca vaccine. However, this study was not randomized in the way that the vaccine trials were, which is the type of study that can definitively determine causality. The current research also shows that the risk of these neurodegenerative complications is much greater following a COVID-19 infection, and that risks of the vaccines are outweighed by the benefits. This is currently one of the only reputable studies that has this finding. More research is needed to confirm the findings and to understand how much risk of neurodegenerative diseases is increased by following COVID-19 vaccines, if at all.
April 30, 2021: The U.S. Department of Health and Human Services updated the Vaccine Adverse Event Reporting System (VAERS) database on April 30, 2021. While there is still no evidence indicating that COVID-19 vaccinations can cause prion-related diseases, the VAERS database now reports a very small number of relevant cases (ex. Alzheimer's type dementia, multiple sclerosis, neurological symptoms). The number of reported cases for these symptoms were mostly in the single digits (occasionally in the teens), out of over 100 million people in the U.S. who received at least one vaccine dose, so it is incredibly rare for neurological issues to be reported after COVID-19 vaccination. Patients may experience symptoms due to a variety of reasons, including underlying health conditions, so VAERS reports do not necessarily mean that symptoms were caused by vaccination or that a link to vaccination has been confirmed. Additionally, VAERS relies on reporting from vaccine providers and provides the disclaimer that "reports may include incomplete, inaccurate, coincidental and unverified information." Research to develop safe mRNA vaccines has been happening for decades before the COVID-19 pandemic, and experts agree that mRNA vaccines remain highly safe and effective for the vast majority of people. At this time, there is no scientific evidence to suggest that prior-related disorders could be caused by mRNA vaccination.
February 3, 2022: A small amount of new data has emerged that suggests a possible association between COVID-19 vaccines and a slight increase in risk of certain neurodegenerative diseases. An October 2021 study found that there was a slight increase in neurodegenerative conditions Guillain–Barré syndrome and Bell's Palsy after the Pfizer-BioNTech vaccine and the AstraZeneca vaccine. However, this study was not randomized in the way that the vaccine trials were, which is the type of study that can definitively determine causality. The current research also shows that the risk of these neurodegenerative complications is much greater following a COVID-19 infection, and that risks of the vaccines are outweighed by the benefits. This is currently one of the only reputable studies that has this finding. More research is needed to confirm the findings and to understand how much risk of neurodegenerative diseases is increased by following COVID-19 vaccines, if at all.
April 30, 2021: The U.S. Department of Health and Human Services updated the Vaccine Adverse Event Reporting System (VAERS) database on April 30, 2021. While there is still no evidence indicating that COVID-19 vaccinations can cause prion-related diseases, the VAERS database now reports a very small number of relevant cases (ex. Alzheimer's type dementia, multiple sclerosis, neurological symptoms). The number of reported cases for these symptoms were mostly in the single digits (occasionally in the teens), out of over 100 million people in the U.S. who received at least one vaccine dose, so it is incredibly rare for neurological issues to be reported after COVID-19 vaccination. Patients may experience symptoms due to a variety of reasons, including underlying health conditions, so VAERS reports do not necessarily mean that symptoms were caused by vaccination or that a link to vaccination has been confirmed. Additionally, VAERS relies on reporting from vaccine providers and provides the disclaimer that "reports may include incomplete, inaccurate, coincidental and unverified information." Research to develop safe mRNA vaccines has been happening for decades before the COVID-19 pandemic, and experts agree that mRNA vaccines remain highly safe and effective for the vast majority of people. At this time, there is no scientific evidence to suggest that prior-related disorders could be caused by mRNA vaccination.
There is currently no scientific evidence that the COVID-19 mRNA vaccines by Pfizer or Moderna lead to neurodegenerative diseases.
There is currently no scientific evidence that the COVID-19 mRNA vaccines by Pfizer or Moderna lead to neurodegenerative diseases.
Publication
What our experts say
Neurological impacts from COVID-19 infections are now documented in multiple peer-reviewed scientific studies. However, there is currently no scientific evidence that the COVID-19 mRNA vaccines lead to neurodegenerative diseases. Unvaccinated individuals are at higher risk of serious illness from COVID-19 infection, which can cause temporary as well as longer-term neurological impacts in some patients.
In order to receive emergency use authorization in the U.S., the approved mRNA vaccines went through rigorous clinical trials and scientific review. Regulators found serious adverse reactions to be exceedingly rare. Pfizer and Moderna clinical trials included tens of thousands of participants and have not found links between vaccination and neurodegenerative diseases.
A spokesperson for the U.S. Centers for Disease Control and Prevention (CDC) said that the national monitoring body, VAERS (Vaccine Adverse Event Reporting System), had "no reports of prion-related diseases, Alzheimer's disease, or amyotrophic lateral sclerosis (ALS) after COVID-19 vaccination." There is "no evidence to date" for claiming a "causative association between COVID-19 vaccines and these conditions," the spokesperson said.
Vaccines are widely considered highly safe and effective for the vast majority of adults to protect themselves from COVID-19.
False claims link COVID-19 mRNA vaccines to neurodegenerative diseases, and many reference work by anti-vaccinationist J. Bart Classen. Before the COVID-19 pandemic, Classen wrote about the Hib (Haemophilus influenzae type b), making claims based on limited evidencethat have been disputed by other researchers.
On January 18, 2021, a three-page paper by Classen entitled "COVID-19 RNA Based Vaccines and the Risk of Prion Disease" was accepted for publication in Microbiology & Infectious Diseases. Unlike typical scientific papers, this paper by Classen does not include a clear description of methods, nor does it refer to any data for analysis in the results section. The paper inconsistently refers to prion disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD), and other types of neurodegeneration throughout the text. The second paragraph of the discussion section says "prion disease including Alzheimer’s disease, ALS..." despite Alzheimer's disease and ALS being categorized differently than prion diseases.
The conclusion of the paper advances unproven conspiracy theories about the COVID-19 pandemic being caused by bioweapons, despite experts at the World Health Organization and other research institutions concluding that laboratories are "unlikely" to be the origin of COVID-19. Additionally, it is unclear if this paper was peer-reviewed by qualified experts in the field, since the publisher of Microbiology & Infectious Diseases was identified as a predatory open-access publisher on Beall's List.
This paper and the claims referencing it were flagged as suspicious by the online misinformation tracking firm VineSight, and debunked through fact-checking from organizations like The Poynter Institute.
Neurological impacts from COVID-19 infections are now documented in multiple peer-reviewed scientific studies. However, there is currently no scientific evidence that the COVID-19 mRNA vaccines lead to neurodegenerative diseases. Unvaccinated individuals are at higher risk of serious illness from COVID-19 infection, which can cause temporary as well as longer-term neurological impacts in some patients.
In order to receive emergency use authorization in the U.S., the approved mRNA vaccines went through rigorous clinical trials and scientific review. Regulators found serious adverse reactions to be exceedingly rare. Pfizer and Moderna clinical trials included tens of thousands of participants and have not found links between vaccination and neurodegenerative diseases.
A spokesperson for the U.S. Centers for Disease Control and Prevention (CDC) said that the national monitoring body, VAERS (Vaccine Adverse Event Reporting System), had "no reports of prion-related diseases, Alzheimer's disease, or amyotrophic lateral sclerosis (ALS) after COVID-19 vaccination." There is "no evidence to date" for claiming a "causative association between COVID-19 vaccines and these conditions," the spokesperson said.
Vaccines are widely considered highly safe and effective for the vast majority of adults to protect themselves from COVID-19.
False claims link COVID-19 mRNA vaccines to neurodegenerative diseases, and many reference work by anti-vaccinationist J. Bart Classen. Before the COVID-19 pandemic, Classen wrote about the Hib (Haemophilus influenzae type b), making claims based on limited evidencethat have been disputed by other researchers.
On January 18, 2021, a three-page paper by Classen entitled "COVID-19 RNA Based Vaccines and the Risk of Prion Disease" was accepted for publication in Microbiology & Infectious Diseases. Unlike typical scientific papers, this paper by Classen does not include a clear description of methods, nor does it refer to any data for analysis in the results section. The paper inconsistently refers to prion disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD), and other types of neurodegeneration throughout the text. The second paragraph of the discussion section says "prion disease including Alzheimer’s disease, ALS..." despite Alzheimer's disease and ALS being categorized differently than prion diseases.
The conclusion of the paper advances unproven conspiracy theories about the COVID-19 pandemic being caused by bioweapons, despite experts at the World Health Organization and other research institutions concluding that laboratories are "unlikely" to be the origin of COVID-19. Additionally, it is unclear if this paper was peer-reviewed by qualified experts in the field, since the publisher of Microbiology & Infectious Diseases was identified as a predatory open-access publisher on Beall's List.
This paper and the claims referencing it were flagged as suspicious by the online misinformation tracking firm VineSight, and debunked through fact-checking from organizations like The Poynter Institute.
Context and background
Despite recent claims resurfacing in social media about vaccines causing neurodegenerative diseases, there continues to be insufficient evidence to confirm such a link for any ages. There are reported post-vaccination neurologic complications that have been reported, but they remain very rare. There is also new, early research that suggests a possible link between certain COVID-19 vaccines and certain neurodegenerative disorders. These reports and research have also not been proven a causal link between vaccines and neurodegenerative diseases.
The American Academy of Neurology (AAN), the world's largest association of neurologists and neuroscience professionals, recommends COVID-19 vaccination to all eligible patients unless someone has contraindications (a specific situation in which a vaccine or drug should not be used because it may be harmful to the person due to vaccine contents and preexisting conditions).
Unlike COVID-19 vaccines, there is data to suggest that COVID-19 infection could lead to neurodegenerative risks. For instance, early research suggests a relationship between COVID-19 and risk of Alzheimer's. An article by the American Heart Association states that in order to reduce future neurodegenerative risks like dementia as a result of COVID-19 infection, vaccination against COVID-19 is recommended.
Despite recent claims resurfacing in social media about vaccines causing neurodegenerative diseases, there continues to be insufficient evidence to confirm such a link for any ages. There are reported post-vaccination neurologic complications that have been reported, but they remain very rare. There is also new, early research that suggests a possible link between certain COVID-19 vaccines and certain neurodegenerative disorders. These reports and research have also not been proven a causal link between vaccines and neurodegenerative diseases.
The American Academy of Neurology (AAN), the world's largest association of neurologists and neuroscience professionals, recommends COVID-19 vaccination to all eligible patients unless someone has contraindications (a specific situation in which a vaccine or drug should not be used because it may be harmful to the person due to vaccine contents and preexisting conditions).
Unlike COVID-19 vaccines, there is data to suggest that COVID-19 infection could lead to neurodegenerative risks. For instance, early research suggests a relationship between COVID-19 and risk of Alzheimer's. An article by the American Heart Association states that in order to reduce future neurodegenerative risks like dementia as a result of COVID-19 infection, vaccination against COVID-19 is recommended.
Resources
- The coronavirus vaccine doesn’t cause Alzheimer’s, ALS (PolitiFact)
- Prion disease (U.S. Centers for Disease Control and Prevention)
- Prion disease (University of California San Francisco)
- Origins of the SARS-CoV-2 virus (World Health Organization)
- List of Potential Predatory Journals and Publishers (Beall's List)
- Selected Adverse Events Reported after COVID-19 Vaccination (U.S. Centers for Disease Control and Prevention)
- How COVID-19 attacks the brain (American Psychological Association)
- How COVID-19 can damage the brain (Nature)
- The potential neurological effect of the COVID-19 vaccines: A review (Acta Neurologica Scandinavica - Wiley Online Library)
- Position Statement: COVID-19 Vaccination (American Academy of Neurology)
- AAN Issues Formal Position Statement on COVID-19 Vaccine (Medpage today)
- Fact Check-No evidence that Pfizer’s COVID-19 vaccine causes Alzheimer’s disease (Reuters)
- What are the links between COVID-19, brain harm and dementia risk? (American Health Association News)
- COVID-19 Associated with Long-Term Cognitive Dysfunction, Acceleration of Alzheimer’s Symptoms (Alzheimer's Association)
-
Neurological complications after first dose of COVID-19 vaccines and SARS-CoV-2 infection (Nature Medicine) COVID-19 and Vaccination in the Setting of Neurologic Disease (Neurology)
- The coronavirus vaccine doesn’t cause Alzheimer’s, ALS (PolitiFact)
- Prion disease (U.S. Centers for Disease Control and Prevention)
- Prion disease (University of California San Francisco)
- Origins of the SARS-CoV-2 virus (World Health Organization)
- List of Potential Predatory Journals and Publishers (Beall's List)
- Selected Adverse Events Reported after COVID-19 Vaccination (U.S. Centers for Disease Control and Prevention)
- How COVID-19 attacks the brain (American Psychological Association)
- How COVID-19 can damage the brain (Nature)
- The potential neurological effect of the COVID-19 vaccines: A review (Acta Neurologica Scandinavica - Wiley Online Library)
- Position Statement: COVID-19 Vaccination (American Academy of Neurology)
- AAN Issues Formal Position Statement on COVID-19 Vaccine (Medpage today)
- Fact Check-No evidence that Pfizer’s COVID-19 vaccine causes Alzheimer’s disease (Reuters)
- What are the links between COVID-19, brain harm and dementia risk? (American Health Association News)
- COVID-19 Associated with Long-Term Cognitive Dysfunction, Acceleration of Alzheimer’s Symptoms (Alzheimer's Association)
-
Neurological complications after first dose of COVID-19 vaccines and SARS-CoV-2 infection (Nature Medicine) COVID-19 and Vaccination in the Setting of Neurologic Disease (Neurology)
