Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. will come under bipartisan pressure in the Senate on Thursday to show his shake-up at the Centers for Disease Control and Prevention (CDC) has not left the country more vulnerable to outbreaks and other public health threats.

Kennedy pushed out CDC Director Susan Monarez last week after she battled with him over vaccine policies, prompting the resignations of four senior leaders at the health agency, who said Kennedy was politicizing public health.

Monarez, the first-ever CDC director to be confirmed by the Senate, was on the job for only about a month before she was removed.

Now, Kennedy is facing calls for his resignation from Democrats and current and former HHS staff, while some Republicans have signaled they are uneasy — at best — over his leadership, ahead of a Senate Finance Committee hearing at 10 a.m. EDT Thursday.

Sen. John Kennedy (R-La.), who voted to confirm the HHS secretary, said the “chaos” at public health agencies needs to stop.

“I don't know who's right or who's wrong in the debate that he has provoked with respect to vaccines. I do know that it has not increased confidence in the institution of public health in the chaos that he's created. They need to get their business straight,” he said.

“You can't have the institution of public health in turmoil. You can't have it.”

Senate Majority Leader John Thune (R-S.D.) told reporters Robert F. Kennedy Jr. would face "hard questions" in the hearing.

"He's got to take responsibility for, you know: We confirm these people. We go through a lot of work to get them confirmed. And they’re in office a month?"

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