President Trump has repeatedly promoted the debunked claim that vaccines cause autism

President Donald Trump marked World Autism Awareness Day by lighting up the White House in the color blue on Sunday.

And Twitter marked the day by shining a light on the falsehoods Trump has spread about autism and its causes.

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In recent years, Trump has repeatedly promoted the claim that vaccines cause autism — a conspiracy theory without any scientific proof to support it.

In March 2014, he took to Twitter to call for a halt to government vaccination programs, suggesting they were the cause of a rise in autism reported by the CDC at the time.

In February 2015, a few months before he launched his presidential campaign, Trump repeated his claim that vaccines could cause “horrible autism.”

He also said at the time that he was “totally pro-vaccine” but just wanted to see them given in smaller doses.

And shortly before his inauguration in January, Trump met with JFK’s nephew, anti-vaccine activist Robert F. Kennedy Jr., who said the soon-to-be president had asked him to lead a new government commission on vaccine safety and scientific integrity.

Trump spokeswoman Hope Hicks said at the time that Trump was “exploring the possibility of forming a committee on autism, which affects so many families,” but that no final decisions had been made.

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Nevertheless, the possibility sparked alarm among medical experts who warned that such a committee would “endanger children by confusing parents about the vital need to get them vaccinated,” The New York Times reported.

Many on Twitter pointedly reminded Trump of his anti-vaccine statements after he tweeted about the “Light It Up Blue” campaign for autism awareness.

Some also hinted that Trump appeared to be copying the Obamas, who famously lit up the White House in rainbow colors after the Supreme Court ruled in favor of gay marriage.

House Speaker Paul Ryan was also criticized for tweeting about autism awareness, with many saying his and Trump’s Republican health care bill would leave people with autism with either no health care coverage or unaffordable coverage.

White House Press Secretary Sean Spicer said the president decided to observe World Autism Day at the suggestion of his friend and supporter Bob Wright, who along with his late wife, Suzanne, founded the advocacy organization Autism Speaks.

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