Weldon, 71, is a medical doctor and former lawmaker who served in the House, representing Florida. The former congressman has been a strong critic of the CDC, especially its vaccine program. Weldon has championed the long-debunked notion that thimerosal, a vaccine preservative, is linked to autism.

Weldon has questioned the safety of some vaccines and advocated for limits on abortion. He'll be the first CDC director to face Senate confirmation.