Dave Weldon’s long record of promoting the disproven link between vaccines and autism raises concerns among some public health experts about his ability to run the CDC.

Trump did not explicitly say in the interview that vaccines cause autism, a false claim that traces back to a retracted study from the 1990s. When pressed on the issue, Trump said his administration will complete “very serious testing,” after which “we will know for sure what's good and what's not good.”

President-elect Donald Trump would not denounce the false conspiracy theory that childhood vaccines have caused autism rates to rise, saying instead that he would listen to Robert F. Kennedy Jr., the anti-vaccine advocate he wants to lead the Department of Health and Human Services.