Extensive investigation into
vaccines
A vaccine is a biological preparation that provides active acquired immunity
The adaptive immune system, also known as the acquired immune system, is a subsystem of the immune system that is composed of specialized, systemic cells and pro ...
and
autism
The autism spectrum, often referred to as just autism or in the context of a professional diagnosis autism spectrum disorder (ASD) or autism spectrum condition (ASC), is a neurodevelopmental condition (or conditions) characterized by difficulti ...
has shown that there is no relationship between the two,
causal
Causality (also referred to as causation, or cause and effect) is influence by which one event, process, state, or object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cau ...
or otherwise,
and that the
vaccine ingredients do not cause it. Vaccinologist
Peter Hotez
Peter Jay Hotez (born May 5, 1958) is an American scientist, pediatrician, and advocate in the fields of global health, vaccinology, and neglected tropical disease control. He serves as founding dean of the National School of Tropical Medicine, P ...
researched the growth of the false claim and concluded that its spread originated with
Andrew Wakefield
Andrew Jeremy Wakefield (born September 3, 1956) is a British anti-vaccine activist, former physician, and discredited academic who was struck off the medical register for his involvement in ''The Lancet'' MMR autism fraud, a 1998 study that ...
's
fraudulent 1998 paper, with no prior paper supporting a link.
Despite the
scientific consensus
Scientific consensus is the generally held judgment, position, and opinion of the majority or the supermajority of scientists in a particular field of study at any particular time.
Consensus is achieved through scholarly communication at confe ...
for the absence of a relationship
and the retracted paper, the
anti-vaccination movement
Vaccine hesitancy is a delay in acceptance, or refusal, of vaccines despite the availability of vaccine services and supporting evidence. The term covers refusals to vaccinate, delaying vaccines, accepting vaccines but remaining uncertain abou ...
at large continue to promote myths,
conspiracy theories
A conspiracy theory is an explanation for an event or situation that invokes a conspiracy by sinister and powerful groups, often political in motivation, when other explanations are more probable.Additional sources:
*
*
*
* The term has a nega ...
, and misinformation linking the two.
A developing tactic appears to be the "promotion of irrelevant research
san active aggregation of several questionable or peripherally related research studies in an attempt to justify the science underlying a questionable claim."
Claimed mechanisms
The claimed mechanisms have changed over time, in response to evidence refuting each in turn.
Vaccine-derived measles virus
The idea of a link between the
MMR vaccine
The MMR vaccine is a vaccine against measles, mumps, and rubella (German measles), abbreviated as ''MMR''. The first dose is generally given to children around 9 months to 15 months of age, with a second dose at 15 months to 6 years of age, ...
and autism came to prominence after the publication of a paper by
Andrew Wakefield
Andrew Jeremy Wakefield (born September 3, 1956) is a British anti-vaccine activist, former physician, and discredited academic who was struck off the medical register for his involvement in ''The Lancet'' MMR autism fraud, a 1998 study that ...
and others in ''
The Lancet
''The Lancet'' is a weekly peer-reviewed general medical journal and one of the oldest of its kind. It is also the world's highest-impact academic journal. It was founded in England in 1823.
The journal publishes original research articles, ...
'' in 1998. This paper, which was
retracted in 2010 and whose publication led to Wakefield being
struck off
The General Medical Council (GMC) is a public body that maintains the official register of medical practitioners within the United Kingdom. Its chief responsibility is to "protect, promote and maintain the health and safety of the public" by c ...
the UK medical register, has been described as "the most damaging medical hoax of the last 100 years".
Wakefield's core claim was that he had isolated evidence of vaccine-strain measles virus RNA in the intestines of autistic children, leading to a condition he termed ''
autistic enterocolitis
The ''Lancet'' MMR autism fraud centered on the publication in February 1998 of a fraudulent research paper titled "Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children" in ''The Lancet''. T ...
'' (this was never recognised or adopted by the scientific community). This finding was later shown to be due to errors made by the laboratory where the
polymerase chain reaction
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it (or a part of it) t ...
(PCR) tests were performed.
The CDC, the IOM of the
National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...
,
and the UK
National Health Service
The National Health Service (NHS) is the umbrella term for the publicly funded healthcare systems of the United Kingdom (UK). Since 1948, they have been funded out of general taxation. There are three systems which are referred to using the " ...
have all concluded that there is no link between the MMR vaccine and autism. A systematic review by the
Cochrane Library
The Cochrane Library (named after Archie Cochrane) is a collection of databases in medicine and other healthcare specialties provided by Cochrane and other organizations. At its core is the collection of Cochrane Reviews, a database of system ...
concluded that there is no credible link between the MMR vaccine and autism, that MMR has prevented diseases that still carry a heavy burden of death and complications, that the lack of confidence in MMR has damaged public health, and that the design and reporting of safety outcomes in MMR vaccine studies are largely inadequate.
In 2009, ''
The Sunday Times
''The Sunday Times'' is a British newspaper whose circulation makes it the largest in Britain's quality press market category. It was founded in 1821 as ''The New Observer''. It is published by Times Newspapers Ltd, a subsidiary of News UK, whi ...
'' reported that Wakefield had manipulated patient data and misreported results in his 1998 paper, creating the appearance of a link with autism. A 2011 article in the
''British Medical Journal'' described how the data in the study had been falsified by Wakefield so that it would arrive at a predetermined conclusion.
An accompanying editorial in the same journal described Wakefield's work as an "elaborate
fraud
In law, fraud is intentional deception to secure unfair or unlawful gain, or to deprive a victim of a legal right. Fraud can violate civil law (e.g., a fraud victim may sue the fraud perpetrator to avoid the fraud or recover monetary compens ...
" that led to lower vaccination rates, putting hundreds of thousands of children at risk and diverting energy and money away from research into the true cause of autism.
A special court convened in the United States to review claims under the
National Vaccine Injury Compensation Program
The Office of Special Masters of the U.S. Court of Federal Claims, popularly known as "vaccine court", administers a no-fault system for litigating vaccine injury claims. These claims against vaccine manufacturers cannot normally be filed in st ...
ruled on February 12, 2009, that parents of autistic children are not entitled to compensation in their contention that certain vaccines caused autism in their children.
Thiomersal
Thiomersal
Thiomersal (INN), or thimerosal (USAN, JAN), is an organomercury compound. It is a well-established antiseptic and antifungal agent.
The pharmaceutical corporation Eli Lilly and Company gave thiomersal the trade name Merthiolate. It has been u ...
(spelled "thimerosal" in the US) is an
antifungal
An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as crypto ...
preservative used in small amounts in some multi-dose vaccines (where the same vial is opened and used for multiple patients) to prevent contamination of the vaccine.
Thiomersal contains
ethylmercury
Ethylmercury (sometimes ethyl mercury) is a cation composed of an organic CH3CH2- species (an ethyl group) bound to a mercury(II) centre, making it a type of organometallic cation, and giving it a chemical formula C2H5Hg+. The main source of eth ...
, a mercury compound which is related to, but significantly less toxic than, the
neurotoxic
Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specificall ...
pollutant
methylmercury
Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a ...
. Despite decades of safe use, public campaigns prompted the
Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
(CDC) and the
American Academy of Pediatrics
The American Academy of Pediatrics (AAP) is an American professional association of pediatricians, headquartered in Itasca, Illinois. It maintains its Department of Federal Affairs office in Washington, D.C.
Background
The Academy was founded ...
(AAP) to request vaccine makers to remove thiomersal from vaccines as quickly as possible on the
precautionary principle
The precautionary principle (or precautionary approach) is a broad epistemological, philosophical and legal approach to innovations with potential for causing harm when extensive scientific knowledge on the matter is lacking. It emphasizes caut ...
. Thiomersal is now absent from all common US and European vaccines, except for some preparations of
influenza vaccine
Influenza vaccines, also known as flu shots, are vaccines that protect against infection by influenza viruses. New versions of the vaccines are developed twice a year, as the influenza virus rapidly changes. While their effectiveness varies fr ...
.
(Trace amounts remain in some vaccines due to production processes, at an approximate maximum of 1 microgramme, around 15% of the average daily mercury intake in the US for adults and 2.5% of the daily level considered tolerable by the
WHO
Who or WHO may refer to:
* Who (pronoun), an interrogative or relative pronoun
* Who?, one of the Five Ws in journalism
* World Health Organization
Arts and entertainment Fictional characters
* Who, a creature in the Dr. Seuss book '' Horton He ...
.) The action sparked concern that thiomersal could have been responsible for autism.
The idea that thiomersal was a cause or trigger for autism is now considered disproven, as incidence rates for autism increased steadily even after thiomersal was removed from childhood vaccines.
There is no accepted scientific evidence that exposure to thiomersal is a factor in causing autism.
Under the FDA Modernization Act (FDAMA) of 1997, the FDA conducted a comprehensive review of the use of thimerosal in childhood vaccines. Conducted in 1999, this review found no evidence of harm from the use of thimerosal as a vaccine preservative, other than local hypersensitivity reactions. Despite this, starting in 2000, parents in the United States pursued legal compensation from a federal fund arguing that thiomersal caused autism in their children.
A 2004
Institute of Medicine
The National Academy of Medicine (NAM), formerly called the Institute of Medicine (IoM) until 2015, is an American nonprofit, non-governmental organization. The National Academy of Medicine is a part of the National Academies of Sciences, E ...
(IOM) committee favored rejecting any causal relationship between thiomersal-containing vaccines and autism
and rulings from the
vaccine court
The Office of Special Masters of the U.S. Court of Federal Claims, popularly known as "vaccine court", administers a no-fault system for litigating vaccine injury claims. These claims against vaccine manufacturers cannot normally be filed in s ...
in three test claims in 2010 established the precedent that thiomersal is not considered a cause of autism.
Vaccine overload
Following the belief that individual vaccines caused autism was the idea of vaccine overload, which claims that too many vaccines at once may overwhelm or weaken a child's immune system and lead to adverse effects.
Vaccine overload became popular after the Vaccine Injury Compensation Program accepted the case of nine year old
Hannah Poling. Hannah had encephalopathy putting her on the autism spectrum disorder, which was believed to have worsened after getting multiple vaccines at nineteen months old.
There have been multiple cases reported similar to this one, which led to the belief that vaccine overload caused autism. However, scientific studies show that vaccines do not overwhelm the immune system.
In fact, conservative estimates predict that the immune system can respond to thousands of viruses simultaneously.
It is known that vaccines constitute only a tiny fraction of the pathogens already naturally encountered by a child in a typical year.
[ Common fevers and middle ear infections pose a much greater challenge to the immune system than vaccines do. Other scientific findings support the idea that vaccinations, and even multiple concurrent vaccinations, do not weaken the immune system][ or compromise overall immunity and, furthermore, evidence that autism has any immune-mediated pathophysiology has still not been found.][
]
Aluminium
Since mercury compounds in vaccines have been definitively ruled out as a cause of autism, some anti-vaccine activists propose aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
salts as the cause of ASD. This is based in part on the erroneous popular belief that aluminium causes Alzheimer disease
Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As t ...
. There is no good scientific evidence that aluminium salts are linked to autism, but anti-vaccination activists commonly cite a number of papers which claim that there is in fact a link. These are mainly published in predatory open access journals, where peer-review
Peer review is the evaluation of work by one or more people with similar competencies as the producers of the work (peers). It functions as a form of self-regulation by qualified members of a profession within the relevant field. Peer review ...
is virtually non-existent. One, in the mainstream ''Journal of Inorganic Biochemistry
The ''Journal of Inorganic Biochemistry'' is a monthly peer-reviewed scientific journal covering research on the inorganic aspects of biochemistry, such as metalloenzymes and metallobiomolecules. The journal was established in 1971 as ''Bioinor ...
'', was subsequently retracted. Work conducted by Christopher Shaw, Christopher Exley and Lucija Tomljenovic has been funded by the anti-vaccination Dwoskin Family Foundation. The work published by Shaw et al. has been discredited by the World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
.
Celebrity involvement
Some celebrities have spoken out on their views that autism is related to vaccination, including: Jenny McCarthy
Jennifer McCarthy Wahlberg (' Jennifer Ann McCarthy; born November 1, 1972) is an American actress, model, and television personality. She began her career in 1993 as a nude model for ''Playboy'' magazine and was later named their Playmate of ...
, Kristin Cavallari
Kristin Elizabeth Cavallari (born January 5, 1987) is an American television personality, fashion designer, actress and author. She first rose to fame in 2004 as a cast member on the popular MTV reality television series '' Laguna Beach: The Re ...
, Toni Braxton
Toni Michele Braxton (born October 7, 1967) is an American Contemporary R&B, R&B singer, songwriter, actress and television personality. She has sold over 70 million records worldwide and is one of the best-selling female artists in history. ...
, Robert De Niro
Robert Anthony De Niro Jr. ( , ; born August 17, 1943) is an American actor. Known for his collaborations with Martin Scorsese, he is considered to be one of the best actors of his generation. De Niro is the recipient of various accolades ...
, Jim Carrey
James Eugene Carrey (; born January 17, 1962) is a Canadian-American actor, comedian and artist. Known for his energetic slapstick performances, Carrey first gained recognition in 1990, after landing a role in the American sketch comedy te ...
, Bill Maher
William Maher (; born January 20, 1956) is an American comedian, writer, producer, political commentator, actor, and television host. He is known for the HBO political talk show ''Real Time with Bill Maher'' (2003–present) and the similar la ...
, and Pete Evans
Peter Daryl Evans (born 29 August 1973) is an Australian chef, and former television presenter, who was a former judge of the competitive cooking show ''My Kitchen Rules''. Evans has been heavily criticised for spreading misinformation about ...
.
McCarthy, one of the most outspoken celebrities on the topic, has said her son Evan's autism diagnosis was a result of the MMR vaccine
The MMR vaccine is a vaccine against measles, mumps, and rubella (German measles), abbreviated as ''MMR''. The first dose is generally given to children around 9 months to 15 months of age, with a second dose at 15 months to 6 years of age, ...
, despite the comprehensive evidence to the contrary. She authored ''Louder than Words: A Mother's Journey in Healing Autism'' and co-authored ''Healing and Preventing Autism.'' She also founded an organization called Generation Rescue, which provides resources for families affected by autism.
In a September 2015 CNN Presidential debate, Donald Trump
Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who served as the 45th president of the United States from 2017 to 2021.
Trump graduated from the Wharton School of the University of Pe ...
claimed to know of a 2-year-old who recently got a combined vaccine, developed a fever and is now on the autism spectrum.
Robert F. Kennedy, Jr. is one of the most notable proponents of the anti-vaccine movement. Kennedy published the book ''Thimerosal: Let the Science Speak: The Evidence Supporting the Immediate Removal of Mercury--A Known Neurotoxin--From Vaccines''. He is also the founder and chairman of the board of Children's Health Defense
Children's Health Defense is an American 501(c)(3) nonprofit activist group mainly known for anti-vaccine propaganda and has been identified as one of the main sources of misinformation on vaccines. Founded under the name World Mercury Project ...
, a group and website widely known for its anti-vaccination stance.
Public opinion
A December 2020 poll in the United States found 12% of Americans incorrectly believed there is evidence that vaccinations cause autism, and 37% were not sure.Even If It's 'Bonkers,' Poll Finds Many Believe QAnon And Other Conspiracy Theories
/ref>
References
{{Vaccine safety
Vaccine hesitancy
Autism pseudoscience
Conspiracy theories
Conspiracy theories promoted by Donald Trump