Dave Weldon is likely to be questioned about measles infections, a plan to study a debunked link between vaccines and autism, and the ongoing bird flu outbreak.

The White House has withdrawn its nomination of Dr. Dave Weldon to serve as the director of the US Centers for Disease Control and Prevention, two Trump administration official familiar with the decision told CNN.

Weldon was told Wednesday night that his nomination was being withdrawn, another Trump administration official said. The White House decided to pull Weldon’s nomination when it became clear that he would not have the votes to be favorably reported out of committee because of his past controversial comments about vaccines, the official said.