Republican presidential candidates Dr. Ben Carson, Donald Trump and Jeb Bush line up for a photo op before the CNN Republican Debate begins at the Ronald Reagan Presidential Library and Museum, Sept. 16, 2015, in Simi Valley, Calif.
Photo by Mark Peterson/Redux for MSNBC

No, vaccines have not caused an autism ‘epidemic’

Updated

Donald Trump likes to say that his top qualification for the White House is his business acumen. But at Wednesday’s  Republican presidential debates, the GOP front-runner took on the ill-advised role of doctor-in-chief, suggesting that vaccines have caused an “epidemic” of autism, a complex brain disorder that afflicts millions of Americans.  

Trump has a long history of thoroughly debunked opinions on autism, which he has described as “doctor-inflicted” and caused by a “monstrous” vaccine trend nationwide. But his comments at the Ronald Reagan Presidential Library reached a dangerous new level, coming amid a rise in measles and other diseases as more parents refuse to vaccinate their children.

The two actual doctors on the stage—retired neurosurgeon Ben Carson and Kentucky Sen. Rand Paul—tried to fact check Trump in real time. On Thursday, Democratic presidential candidate Bernie Sanders did the same, citing the overwhelming science that says there’s no connection between vaccines and autism.

RELATED: The winners and losers from last night’s GOP debate

But Trump took a more anecdotal approach. “Autism has become an epidemic. Twenty-five years ago, 35 years ago, you look at the statistics, not even close. It has gotten totally out of control,” he said during the debate, before devolving into a sentimental story about a girl who he believes caught autism from the tip of a doctor’s needle. 

“Just the other day,” he said, “2 years old, 2-and-a-half years old, a child, a beautiful child went to have the vaccine, and came back, and a week later got a tremendous fever, got very, very sick, now is autistic.”  

Autism rates are indeed going up, but experts attribute that to better awareness and diagnosis, not the size or frequency of vaccines. “There is no link between vaccines and autism,” the Centers for Disease Control and Prevention (CDC) declares in an unusually direct headline on its website. 

The fear about vaccines and autism can be traced back to a 1998 paper, which has since been retracted and declared an “elaborate fraud” by a team of British researchers. The doctor who produced the study misrepresented or altered the medical histories of 12 patients, the researchers found, accusing him of doing long lasting damage to public health. That doctor is no longer allowed to practice medicine in his native England, according to the government. 

Meanwhile, hundreds of other doctors have followed up with studies of their own. They’ve tested vaccines in their current form—and in their current dosage—and found no link to autism. In 2011, for example, the Institutes of Medicine published an 866-page report on eight vaccines given to children, and found that with rare exceptions—unrelated to autism—vaccines are very safe. The CDC itself has conducted or funded nine studies that have found no link between vaccines and autism. 

RELATED: 5 takeaways from the GOP debate

On the debate stage, Carson tried to explain all this to Trump. “Well, let me put it this way,” he said. “There have been numerous studies, and they have not demonstrated that there is any correlation between vaccinations and autism.” A few minutes later he added: “The fact of the matter is, we have extremely well-documented proof that there’s no autism associated with vaccinations.”  

Paul tried to do the same. “A second opinion?” he joked. “One of the greatest medical discoveries of all times was—were the vaccines, particularly for smallpox. And if you want to read a story, it’s called The Speckled Monster, it’s an amazing story.” He added: “George Washington wouldn’t let his wife visit until she got vaccinated. So I’m all for vaccines.”  

At that point Trump softened somewhat, saying he’s “all for” vaccines. He just wants them “a little smaller” and spaced out over “a longer period of time.”

Donald Trump and Vaccinations

No, vaccines have not caused an autism 'epidemic'

Updated