By Gia Miller
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For close to three decades, researchers have sought to prove or disprove a single theory: the MMR vaccine causes regressive autism, a condition where a child who appears to be developing typically loses language and social skills. This occurs during their second year of life, which is also when most children receive their first dose of the MMR vaccine (the recommended age is 12-15 months). But is it causation or correlation?
The earliest published claim we could find that MMR causes regressive autism is in a study published in 1998, which we touched upon in our vaccine timeline. Here are more details about that infamous study and what happened next. We are only presenting you with facts we could verify from either the original source or at least two reputable sources (we took this approach for the entire timeline).
Editor’s Note: This article is part of our vaccine timeline, which appeared in our May/June 2025 issue.
1998
The British medical journal Lancet publishes a study led by Andrew Wakefield, a gastroenterologist/senior lecturer at the Royal Free Hospital. Of note, Wakefield’s contract with Royal Free Hospital contained a stipulation stating he had “no involvement in the clinical management of patients.” Wakefield and 12 other researchers conclude that the measles, mumps and rubella (MMR) vaccination causes regressive autism. This finding was based on a study of only 12 children. Despite the tiny sample size and other questionable components, the paper gains significant publicity, and MMR vaccination rates begin to drop.
2000
The U.S. earns its measles elimination status, which is widely considered one of the biggest public health achievements in the nation’s history.
2004
On February 22, journalist Brian Deer publishes the results of his four-month investigation in the U.K.’s The Sunday Times. Deer reveals Wakefield, prior to the study’s release, was paid £55,000 by attorneys “seeking evidence to use against vaccine manufacturers.” And out of the 12 children in the study, four or five were “covered by the legal aid study…Wakefield did not tell his colleagues or medical authorities of this conflict of interest either during or after the research. The children were subjected to a battery of invasive procedures, including colonoscopies and lumbar punctures.”
Wakefield’s colleagues are stunned. Deer quotes Simon Murch, one of the leading doctors involved with Wakefield’s research, saying, “We never knew anything about the £55,000 — he had his own separate research fund. All of us were surprised . . . We are pretty angry.” Deer’s article also explains that the “research paper published in The Lancet contained no scientific evidence of a link with MMR, only the “association” made by parents.”
On March 6, 10 of the 12 researchers issued a retraction in The Lancet, stating, “We wish to make it clear that in this paper no causal link was established between the MMR vaccine and autism as the data were insufficient. However, the possibility of such a link was raised and consequent events have had major implications for public health. In view of this, we consider now is the appropriate time that we should together formally retract the interpretation placed upon these findings in the paper, according to precedent.”
2006
In June, the British General Medical Council says it will hold hearings into Wakefield’s conflicts of interest and research misconduct.
2007
The BGMC’s Fitness to Practise Panel begins their hearings in July. There are 217 days of hearings over 2.5 years.
2010
The BGMC delivers its preliminary verdicts in January 2010 and final decision in May 2010.
They conclude Wakefield falsely stated children’s diagnoses, didn’t report pre-existing medical concerns in five children, and fabricated the timing of symptoms to create a closer link to the MMR vaccine and autism. They also find three of the nine children reported as having regressive autism didn’t have autism at all, and Wakefield performed invasive procedures without a clinical reason or ethical approval. Plus, they verify all information Deer reported.
Wakefield was stripped of his medical license, and the Lancet fully retracted his paper. During and since this time, numerous well-designed studies have shown no association/causation linking autism to the MMR vaccine.
2018
A measles outbreak begins in NY on September 30 and lasts 11.5 months. The outbreak officially ends on September 3, 2019, thanks to almost 34,000 children receiving the MMR vaccine in highly infected areas; 1,645 confirmed cases across 31 states were related to the outbreak. It’s the highest number of cases since 1994. It almost results in the U.S. losing its measles elimination status, which occurs when a virus has spread continuously for an entire year.
2019
A Danish study with 657,461 children concluded there is no association/causation linking autism to the MMR vaccine. It is the largest study on this topic to date.
2025
In January the first cases of measles are reported in Texas, leading to an outbreak that has now spread, with at least 916 confirmed or probable cases (819 related to outbreaks and 97 isolated cases, typically related to international travel) in 30 states as of April 25. The largest outbreak remains in Texas, with almost 600 reported cases. At least 85 people have been hospitalized, and only 3% of those infected received one or two doses of the MMR vaccine. Two children have died in Texas (the first measles-related deaths since 2015), and one adult in New Mexico. Globally, there’s an outbreak in Mexico with over 400 confirmed cases and one death as of April 24. It’s believed to have begun when an unvaccinated 6-year-old from Texas traveled to Mexico. There’s also an outbreak in Canada with more than 1,069 confirmed & probable cases and no reported deaths as of April 25.
On March 21, Texas officials said they believe the outbreak may continue for a year, which means the U.S. would lose its elimination status, and on April 24, Dan Filardo, leader of CDC’s task force for the measles response, was reported saying that this is the largest measles outbreak in 25 years.
This article was published in the May/June 2025 edition of Connect to Northern Westchester.
Gia Miller is an award-winning journalist and the editor-in-chief/co-publisher of Connect to Northern Westchester. She has a magazine journalism degree (yes, that's a real thing) from the University of Georgia and has written for countless national publications, ranging from SELF to The Washington Post. Gia desperately wishes schools still taught grammar. Also, she wants everyone to know they can delete the word "that" from about 90% of their sentences, and there's no such thing as "first annual." When she's not running her media empire, Gia enjoys spending quality time with friends and family, laughing at her crazy dog and listening to a good podcast. She thanks multiple alarms, fermented grapes and her amazing husband for helping her get through each day. Her love languages are food and humor.
