Back to Africa Check

Big data study confirms: Vaccines do not cause autism

A massive 10-year study of more than 600,000 children has again confirmed that vaccines do not cause autism.

Published in the Annals of Medicine in March 2019, it found there was no link between kids being given the vaccine against the childhood diseases of measles, mumps and rubella – the MMR vaccine – and kids developing autism.

The results were reported across the world. One report, by South African radio station Jacaranda FM, was shared on Facebook. A user flagged it as possibly false.

This sent an automatic request asking Africa Check – a member of Facebook’s third-party fact-checking programme – to examine the claim.

It’s true.

Vaccine 'doesn't increase risk of autism'

In the study, researchers from the Statens Serum Institut in Copenhagen followed 657,461 children born from 1999 to 31 December 2010 in Denmark. Putting in over 5 million person-years of work, they tracked the children’s development until 31 August 2013.

The researchers divided the children into two groups: kids who had been given the MMR vaccine, and kids who hadn’t been given the MMR vaccine.

They found there was no difference in the rate of autism in either group of kids.

More than this, as one summary explains, the study found that the MMR vaccine “does not increase the risk of autism, does not trigger autism in susceptible children, and is not associated with clustering of autism cases following vaccination”.

Fraudulent 1998 study started the hoax

But why was the Facebook post flagged as false?

Parents’ worries that the MMR vaccine could trigger autism in their kids have been fuelled by many false claims circulating online for two decades.

It all started with a 1998 study published in the Lancet, a British medical journal. The article has since been retracted.

The study was led by gastroenterologist Andrew Wakefield, MD. It claimed that, in an examination of 12 children, evidence of the measles virus had been found in the digestive systems of kids who had shown symptoms of autism after an MMR vaccination.

As the website History of Vaccines explains, the study “could not demonstrate a causal relationship between MMR vaccination and autism”.

Despite this, “Wakefield suggested in a video released to coincide with the paper’s publication that a causal relationship existed between the MMR and autism”.

Follow the money

Why did Wakefield do this?

In 2004 it emerged that the doctor had been “paid by attorneys seeking to file lawsuits against vaccine manufacturers”. A later investigation also found that Wakefield had filed a patent for his own measles vaccine, which gave him motive to discredit the combined MMR vaccine.

Most of the co-authors of the study distanced themselves from Wakefield’s interpretation. In 2010, the Lancet retracted the paper itself.

Later in 2010 Britain’s General Medical Council banned Wakefield from practising medicine. Its ruling said he was “dishonest, irresponsible and showed callous disregard” for children. He had “abused his position of trust”.

Then, in 2011, British journalist Brian Deer published evidence that Wakefield had committed research fraud by falsifying data on the 12 children used in his 1998 study.

Top 10 global health threat

Yet Wakefield’s fraud continues to harm kids, 20 years later.

As one study says, it has “caused multiple measles outbreaks in Western countries where the measles virus was previously considered eliminated”.

In fact, the World Health Organization lists “vaccine hesitancy” as one of the top 10 threats to global health in 2019 – alongside HIV, Dengue fever, climate change, antibiotic resistance and Ebola. – Mary Alexander (11/04/19)


Further reading

UPDATED: Guide to evaluating health claims, quacks and cures

FACTSHEET: Frequently asked questions about autism in South Africa


Republish our content for free

We believe that everyone needs the facts.

You can republish the text of this article free of charge, both online and in print. However, we ask that you pay attention to these simple guidelines. In a nutshell:

1. Do not include images, as in most cases we do not own the copyright.

2. Please do not edit the article.

3. Make sure you credit "Africa Check" in the byline and don't forget to mention that the article was originally published on

For publishers: what to do if your post is rated false

A fact-checker has rated your Facebook or Instagram post as “false”, “altered”, “partly false” or “missing context”. This could have serious consequences. What do you do?

Click on our guide for the steps you should follow.

Publishers guide

Africa Check teams up with Facebook

Africa Check is a partner in Meta's third-party fact-checking programme to help stop the spread of false information on social media.

The content we rate as “false” will be downgraded on Facebook and Instagram. This means fewer people will see it.

You can also help identify false information on Facebook. This guide explains how.

Add new comment

Restricted HTML

  • Allowed HTML tags: <a href hreflang> <em> <strong> <cite> <blockquote cite> <code> <ul type> <ol start type> <li> <dl> <dt> <dd> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id>
  • Lines and paragraphs break automatically.
  • Web page addresses and email addresses turn into links automatically.
limit: 600 characters

Want to keep reading our fact-checks?

We will never charge you for verified, reliable information. Help us keep it that way by supporting our work.

Become a newsletter subscriber

Support independent fact-checking in Africa.