Claim: MMR vaccine does not cause autism

Question

In recent ariticals and on social media I have hear that these vaccines can cause autism. I have always known that humans can have autism at birth so I was wondering if it is possible to get later in life.

Answer 1

1. Stop and Identify the Source - The claim is presented in a Johns Hopkins Bloomberg School of Public Health Article, which discusses the origins and persistence of the myth linking the MMR vaccine to autism.

2. Investigate the Source - Johns Hopkins Bloomberg School of Public Health is a reputable institution known for rigorous research and public health advocacy. Their information is generally considered reliable and evidence-based.

3. Find Trusted Coverage - Multiple authoritative sources have addressed and debunked the alleged link between the MMR vaccine and autism :

Children's Hospital of Philadelphia - Explains that studies suggesting a link between the MMR vaccine and autism are critically flawed.

UNICEF - Highlights expert opinions confirming that the MMR vaccine does not cause autism.

Mayo Clinic Health System - Emphasizes that vaccinations are crucial for child health and that the autism-vaccine link has been debunked.

Vaccinate Your Family - Details the origin of the myth and confirms that extensive research has found no connection between vaccines and autism.

These sources consistently affirm that there is no credible scientific evidence linking the MMR vaccine to autism.

4. Trace the Original Claim - The myth originated from a 1998 study by Andrew Wakefield, published in The Lancet, which suggested a link between the MMR vaccine and autism. This study was later retracted due to ethical violations and methodological flaws, and Wakefield lost his medical license. Despite the retraction, the claim persisted, partly due to public figures like Robert F. Kennedy Jr., who have continued to promote the discredited theory, contributing to vaccine hesitancy.

Conclusion - The claim that the MMR vaccine does not cause autism is supported by extensive scientific research and endorsed by reputable health organizations. The original suggestion of a link has been thoroughly discredited, and ongoing assertions to the contrary lack credible evidence.

Comments

Your answer was very well organized and showed your process of the SIFT method, which gave a clear response. Many sources and studies have been done on this issue and they haven't found a link to autism. This fear caused a lot of people to choose not to vaccinate themselves and their children, which was done without proper research.

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Amazing fact check! you broke down the statement into plants and investigated the claim thoroughly in order to come to the conclusion proving the claim true. You used many other reliable sources that supported the original claim. Good work.

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I appreciate how you went through the SIFT method very specifically. Your evidence was traced back perfectly to your claim, and it has been proven time and time again that autism has not been linked.

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This is a great fact check. Its very organized and has lots of resources that are reliable and backed up with lots of evidence and you have multiple different resources. I also like how easy it is to understand each concept and how you broke down every different aspect and part of the research.

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Awesome Structured Response! Your knowledge was clear and to the point, and although it seemed like an overall good response, I would suggest adding links to sources. Other than that it's great.

Answer 2

This statement is completely true.  agree that the MMR vaccine does not cause autism. Extensive research, including a 2019 study involving over 650,000 children, found no increased autism risk associated with the vaccine, even among children with autistic siblings. The original 1998 study suggesting a link was retracted and deemed fraudulent. Leading health organizations like the CDC and WHO affirm the vaccine's safety and its critical role in preventing measles, mumps, and rubella. ​

https://publications.aap.org/aapnews/news/13925/Study-MMR-vaccine-not-linked-to-increased-autism?utm_source=chatgpt.com?autologincheck=redirected

Comments

I think you are right here. This claim that the MMR vaccine causes autism has been thoroughly debunked. The Danish study you mentioned is one of the largest and most comprehensive to date. Vaccines save lives and therefore public trust in them matters. Thank you for sharing this source!

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I agree with your fact check. The only thing I would consider is the study being from 2019. That was over 6 years ago, so I wonder if things would be different if you found a study from 2025. I would 100% agree with you, if you were to have found a study that was more recent.

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I think this is a very thought-out comment. I like that you included the specific numbers of the research that add to your credibility. But I also think you would have benefited from finding other sources that would have explained how the false claim got popular or was seen as true. How did it start, who, when, etc.

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This was a great response. I appreciate how you mentioned numbers and research from the 2019 study giving more depth and credibility within your own answer about the matter. I would suggest more sources however, it is always nice to find multiple credible sources. Also, try mentioning why the source is credible and mentioning the author etc. Great work

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This statement seems true. I think the study you chose really backs up your claim because it was done on such a large scale. Since you mentioned the 1998 study being fraudulent, it would be nice to have another reference that goes over that study and why it was debunked. Overall, this is a well-formed response.

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I think it's good that you added the number of children just one study included. Also it's good that you added that some of the most well known health organizations have confirmed vaccines safety. I think it helps people when they hear something recognizable like CDC or WHO to help them belive its a reliable source.

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I really liked how you included the study with 650,000 kids and pointed out that the original study was retracted. That helps clear up a lot of confusion people still have. One thing I’d suggest is maybe adding a second source, like from the CDC or WHO, to make it even stronger and show that multiple trusted organizations agree. But overall, this was well put together.

Answer 3

The false claim linking the MMR vaccine to autism began with a now-retracted and discredited 1998 study in The Lancet by Andrew Wakefield. This study was found to be based on flawed methodology, ethical breaches, and undisclosed conflicts of interest. Despite its retraction and Wakefield's loss of his medical license, the initial misinformation fueled widespread fear. Extensive research involving millions of children across numerous studies by reputable organizations has definitively shown no connection between the MMR vaccine and an increased risk of autism. Autism is understood to be a neurodevelopmental condition with roots in early brain development, not something acquired later in life, although diagnosis can occur at any age.

https://www.google.com/search?q=https://www.cdc.gov/vaccinesafety/concerns/autism.html

https://www.google.com/search?q=https://www.who.int/news-room/q-a-detail/vaccines-and-autism 

Comments

I really liked your response as you made sure to explain where the claim started from originally. This became an argument for many parents during the time of the COVID vaccines as they didn't want to vaccinate their children due to this false fear. There have been many studies done on this topic and none of them have found a link to autism.

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The claim "MMR vaccine does not cause autism" is true. There are common misconceptions that vaccines cause autism. In the John Hopkins article provided above, they highlight "The attention this question got led to a number of large epidemiological studies that looked at kids who were vaccinated with the MMR vaccine and those who weren’t, so there were control groups. And those studies found no association between the MMR vaccine and autism." The original idea that the MMR vaccine and the autism link was from a 1988 study of 12 children. It is likely that parents wanted to put the blame on something, and the timing happened to have more diagnoses of autism. The link provided in the original claim is reliable. John Hopkins is a well-known school that has thorough rules and criteria for publishing articles and studies. I researched other studies to make sure the claim was valid. One article I found titled 'Autism and Vaccines' by the CDC states "Antigens are substances in vaccines that cause the body's immune system to produce disease-fighting antibodies. The results showed that the total amount of antigen from vaccines received was the same between children with ASD and those that did not have ASD." Even when children are given the same number of antigens in the first couple years of life, the antigens were the same. One of the main ingredients in vaccines is Thimerosal. It is used to prevent germs, and it does not cause Autism. The CDC is an official government website that provides factual evidence to the public. The main point of that article was to highlight that there are no ingredients in vaccines that are linked to autism. Mayo Clinic also provides an informative article about debunking the myth of autism being caused by vaccines. "If you've missed those important immunizations, you're exposing your child to these potentially dangerous, even deadly, diseases. Some parents may wonder about the benefits and risks of childhood vaccines. Others have heard myths that vaccines can cause autism." It will always be important to give your children the vaccines they need to stay safe and healthy. Listening to myths you heard may not be the best choice. Its important to do research or consult with a doctor if you have questions. Again, in this article, the 1988 study is mentioned. "The study was reviewed further and retracted. In addition, the author's medical license was revoked due to falsified information."  There have been numerous studies that have debunked the myths of the link between autism and vaccines. Overall, the claim that vaccines do not cause autism is true. The numerous studies have proved that there is no direct correlation between the two.

https://publichealth.jhu.edu/2025/the-evidence-on-vaccines-and-autism
https://www.mayoclinichealthsystem.org/hometown-health/speaking-of-health/autism-vaccine-link-debunked
https://www.cdc.gov/vaccine-safety/about/autism.html

Answer 4

The claim that the MMR vaccine does not cause autism is true. A lot of research has been done, and scientists have found no link between the vaccine and autism. The idea that vaccines cause autism came from a 1998 study, but that study was later found to be fake and was taken down. 

Since then, big studies — like one in 2019 with over 650,000 children — showed the MMR vaccine is safe. Even kids with a family history of autism were not at higher risk after getting the shot.

Trusted health groups like the CDC, World Health Organization, and the American Academy of Pediatrics all say the MMR vaccine is safe and does not cause autism. Vaccines help protect us from serious diseases and are very important for public health.

https://www.cdc.gov/vaccine-safety/about/autism.html?CDC_AAref_Val=https://www.cdc.gov/vaccinesafety/concerns/autism.html

https://publications.aap.org/aapnews/news/13925/Study-MMR-vaccine-not-linked-to-increased-autism?

Comments

Your answer to this claim is thorough and uses highly credible sources such as the CDC. I agree with the information you found, there is no evidence that the MMR vaccine causes autism and this myth stems from anti-vax believers. These people spread this information with no reliable sources after hearing it from someone uneducated on the topic. The National Library of Medicine explains how studies have proven there is no link between those vaccinated and developing autism, instead, the development of autism is strongly linked to genetics.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6768751/

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Thank you for your comment and I liked that you added more articles supporting that these vaccines are safe as well.

Answer 5

The recent news about vaccines causing autism is an act of rumors being spread. This began with RFK Jr, the head of the department of human health and services "In his second day of confirmation hearings, on Jan. 30 before the Senate Committee on Health, Education, Labor and Pensions, Kennedy refused to say that vaccines do not cause autism, despite a large body of evidence showing that there is no link. Kennedy pointed to a flawed paper to suggest there is credible evidence to claim that vaccines cause autism." - https://www.annenbergpublicpolicycenter.org/factcheck-org-kennedy-cites-flawed-paper-in-bid-to-justify-vaccine-autism-link/

This has led to a flee of miss information about vaccines and autism being spread but the facts are, "autism is a neurodevelopmental disorder that typically presents in early childhood," and has nothing to do with vaccines. -https://birthdefects.org/autism/#:~:text=Autism%20Spectrum%20Disorder%20%E2%80%93%20Birth%20Defect%20Fact%20Sheet

This is another case of not believing everything you see a social media and the importance of doing your own research. 

Answer 6

I agree with the statement that the MMR vaccine does not cause autism. The original study that first started this notion of vaccines starting autism is outdated and the paper was redacted. Here's an important quote from the article mentioned "In 1998, a paper describing 12 children who received the MMR and later developed autism or other disorders planted seeds of doubt about the vaccine’s safety. The paper was later retracted, and several large studies have since shown no association between vaccines and autism." To add one more piece of evidence to this claim we can look at this quote from a study from the article of the Children's Hospital of Philadelphia "The risk of autism in the group of vaccinated children was the same as that in unvaccinated children. Furthermore, there was no association between the age at the time of vaccination, the time since vaccination, or the date of vaccination and the development of autism." Overall, the research shows that the MMR is safe for children and does not cause autism. 

Sources :

The Evidence on Vaccines and Autism | Johns Hopkins | Bloomberg School of Public Health

Vaccines and Autism | Children's Hospital of Philadelphia

Answer 7

Claim: MMR Vaccine does not cause autism

First, let's take a look at the source provided. From what I can find, Johns Hopkins Bloomberg School of Public Health can be considered a fairly reputable source. According to the National Library of Medicine, Johns Hopkins has played a decisive role in public health education and research. So this is a great resource. The article focuses on the measles-mumps-rubella (MMR) vaccine that was approved in 1971. There was a paper written by Andrew Wakefield in 1998 however, that stated that twelve children who had received said vaccine had later developed autism or other disorders. The paper was later retracted, but it had already snowballed into many people doubting the safety of the vaccine. It later talks about how there is a lot of science and research to prove that vaccines are safe and do not cause autism. So let’s see if this is true or not.

The CDC talks about how a certain ingredient in vaccines, thimerosal, has been studied and found to not be linked to autism. “Since 2003, there have been nine CDC-funded or conducted studies that have found no link between thimerosal-containing vaccines and ASD. These studies also found no link between the measles, mumps, and rubella (MMR) vaccine and ASD in children.” And since this is the CDC, we can say it’s a reliable source. So that’s another point towards the claim being true.

Let’s find another source just for good measure. A quote from National Academies, “So far, no studies have shown that vaccines given either during pregnancy or after birth cause autism.” They talk about how many scientists have done rigorous studies to find if any aspect of vaccines could cause autism. Some sources they included consist of Healthy Children.org, Annals of Internal Medicine, and the Institute of Medicine. All of these sources provide evidence that vaccines in fact do not cause autism.
In conclusion to this research, I can confidently say that the claim, MMR vaccine does not cause autism, is factually accurate and true. 

Answer 8

The claim that vaccines cause autism has been thoroughly investigated and repeatedly debunked by the global scientific and medical communities. The myth began with a discredited 1998 study that was later retracted due to fraudulent data and unethical conduct. Extensive research—including large-scale studies reviewed by institutions like the CDC, WHO, and Johns Hopkins—has found no credible link between vaccines and autism. Autism is a neurodevelopmental condition that originates in early brain development, though some individuals may not be diagnosed until later in life. A later diagnosis, however, does not mean autism was caused by something like a vaccine—it simply reflects delayed recognition. Vaccines are safe, essential, and do not cause autism.

https://publichealth.jhu.edu/2025/the-evidence-on-vaccines-and-autism

Answer 9

The claim that the MMR vaccine does not cause autism might be true, but the way it's presented is not reliable without supporting evidence. The author fails to reference scientific studies or expert opinions, which are crucial for establishing credibility. Without clear sources or data, readers have no way to verify the accuracy of the claim. A more reliable claim can be found in extensive research, including a large-scale study of over 650,000 children published in Annals of Internal Medicine (2019), which found no link between the MMR vaccine and autism, confirming the vaccine's safety.

https://pmc.ncbi.nlm.nih.gov/articles/PMC6768751/