Health and Human Services Deputy Secretary Jim O'Neill has been tapped as the interim director of the Centers for Disease Control and Prevention (CDC), a White House official confirmed to ABC News.
The selection of O'Neill to temporarily head the agency comes after the very public disagreement between CDC Director Susan Monarez and HHS Secretary Robert F. Kennedy, Jr., which has led to her protested firing.
Jim O'Neill, managing director of Mithril Capital Management, arrives at Trump Tower, January 12, 2017 in New York City.
Drew Angerer/Getty Images
The replacement pick was first reported by the Washington Post.
O'Neill previously worked at HHS under President George Bush from 2002 to 2008. He worked on food safety regulations at the FDA from 2007 to 2008. After working at HHS, he worked for an investment fund and for Silicon Valley billionaire Peter Thiel.
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He has been Kennedy's deputy for the past three months, since early June.
Pressed during his confirmation hearing earlier this year by Senate HELP Committee Chair Bill Cassidy, O'Neill said he supported vaccines but not government mandates.
"I'm very much in favor of vaccines. I think vaccines are one of the greatest public health interventions in human history. They save millions of lives. They will continue to save millions of lives," O'Neill said.
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Cassidy — not satisfied with O'Neill's response — pushed him further, asking how they could keep kids from dying of measles in Texas without requiring vaccines for school, as an example.
"I support CDC recommendations for vaccines. I think that's a central role the CDC has. It's mandated law. It's also an important principle. They have responsibility to recommend good, safe vaccines to everyone," O'Neill said.
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The showdown between Kennedy and Monarez began as a disagreement over demands from Kennedy and Stefanie Spear, his principal deputy chief of staff, for Monarez to support changes to the COVID vaccine policy and the firings of high-level staff, a source familiar with the conversations told ABC News, which Monarez would not commit to.
HHS then announced that Monarez was "no longer director" of the CDC, which touched off a wave of high-level resignations from CDC officials in protest and, ultimately, a fiery response later Wednesday evening from Monarez's lawyers, who said she wouldn't resign.
Following HHS's statement about Monarez's departure, four other senior career officials at the CDC also resigned, according to emails obtained by ABC News.
Asked if the president fully supports Kennedy's changes to vaccine policy, a White House official told ABC News the president trusts Kennedy to do what's right and that he's given him a lot of latitude to enact the Make America Healthy Again vision.
In a letter to CDC staff on Thursday night, Kennedy sought to quell the tension and concern in the agency after days of tumult over its leader, along with the dramatic resignations of multiple high-level officials who had worked there for decades.
"I want you to hear directly from me—this mission remains strong, and so does my full confidence in you," Kennedy said.
"Your daily efforts—often unseen—save lives. Reform does not diminish your work; it strengthens it," he wrote.
It comes after Kennedy has continued to call the CDC "troubled," including in press appearances after Monarez's firing.
"I am committed to working with you to restore trust, transparency, and credibility to the CDC. Your daily efforts—often unseen—save lives. Reform does not diminish your work; it strengthens it," the letter read.