Weldon marks at least the third speed bump the Trump administration hit in its confirmation process after two nominees, former Rep. Matt Gaetz and Chad Chronister, withdrew.

“Dave Weldon is anti-vaccine, anti-woman, and anti-science. He was not qualified to serve as CDC director,” said Colorado Rep. Diana DeGette, the top Democrat on the Energy and Commerce Health Subcommittee in the House.

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.