Scoop: CDC has no Acting Director, sources confirm.

The power vacuum means upcoming vaccine recommendation decisions will legally fall to RFK Jr.

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Image: Chat-GPT 4o.

The United States Centers for Disease Control and Prevention does not have an Acting Director, Inside Medicine has learned—a seemingly unprecedented and legally significant lapse in leadership. Multiple sources in the agency provided details about the development, and three legal scholars independently confirmed the accuracy of the assessment that Dr. Susan Monarez—who served as Acting Director from January 23 through March 24—could no longer lawfully serve (and, in fact, is not currently serving) in that position. And yet, both the CDC’s website and two separate memos sent to staff last week incorrectly stated that Monarez remains in control of the agency.

Here’s why Dr. Monarez cannot legally continue to serve as Acting Director, and first, why the lack of an agency lead, even temporarily, is a potential hazard to everyday Americans.

Why CDC leadership matters.

While the absence of legally authorized leadership at the CDC might seem like a technicality, it could theoretically have immediate and high-stakes consequences for millions of Americans. For example, if a patient with Ebola were to show up in a US emergency department tomorrow, a flurry of technical and practical decisions would become immediately necessary. In that scenario (and many others), the CDC Director or Acting Director would be expected to play a pivotal role in determining and coordinating key aspects of any all-of-government response tasked with preventing a deadly epidemic.

“When the emergency operations center is activated, there are specific functions for the Director," said Dr. Tom Frieden, who served as CDC Director during the Obama administration. In an interview with Inside Medicine, Dr. Frieden emphasized the need for time-sensitive decisions during emergencies.

Even absent a major crisis, however, Frieden noted that many day-to-day decisions must be made by Acting or permanent CDC Directors. “The Director accepts or rejects recommendations of the Advisory Committee on Immunization Practices [ACIP],” he noted. After the committee’s winter meeting was suddenly canceled, ACIP is currently scheduled to meet on April 15-16, Frieden pointed out. “It’s unclear who would be in the position to accept or reject those recommendations at this time.”

Legal scholars I spoke with later, however, had more clarity on the issue. The answer, unsettling though it may be, is that absent a CDC Director, the Secretary of the Department of Health and Human Services alone possesses the legal authority to make these calls. This means that ACIP recommendations on RSV and other vaccines under consideration on next week’s agenda will either have to be approved or vetoed by Robert F. Kennedy Jr. himself—a man confirmed by the US Senate despite his long and troubling history of spreading misinformation about vaccines.

What happened?

On January 23, President Trump named Dr. Susan Monarez as Acting Director of the CDC. That was fine until March 24, when Monarez was named as the nominee for the permanent position. (Dave Weldon, the previous nominee, withdrew from consideration after members of Congress expressed concerns over his record of repeating falsehoods about vaccines. Apparently RFK Jr.’s early performance in his job was disturbing enough to Senators who believe in the science and safety of vaccines that they didn’t want to repeat the mistake of installing another person with a history of spreading vaccine misinformation into a powerful position atop our public health system. Better late than never.)

Immediately after being named Trump’s nominee for permanent CDC Director on March 24, Monarez stopped showing up to leadership meetings at the agency. According to a CDC source, “easily a dozen” routine and ad hoc briefings that had been scheduled with and for Monarez have been canceled during the last two weeks. The topics of the canceled meetings ranged from preparing for the arrival of the permanent Director (which had become moot) and the future of the agency given the unfolding and often opaque HHS reorganization plans (which remain anything but moot).

All of this is what is supposed to happen. That’s according to Professor Anne Joseph O’Connell (Stanford Law), Professor Dorit Reiss (UC Law San Francisco), and Professor Steve Vladeck (Georgetown Law). All three experts independently concluded that it is simply not legally permissible under federal law for the nominee for the permanent CDC Director position to simultaneously function as the Acting Director.

The reasoning behind this policy is sensible. Absent such a rule, the President could just name someone as Acting Director and then subsequently nominate them to the permanent position shortly thereafter. That would mean that the nominee is serving prior to confirmation, a reversal of how the appointments process is supposed to occur.

Who’s the boss?

Many CDC employees seem to have no idea who is running the agency at the moment. In fact, in at least one recent meeting, a rank-and-file employee asked that very question to a manager, a source said. No definitive answer was given.

However, recurring meetings of top leadership are continuing to happen, only now without anyone at the helm. Trump appointee Matt Buzzelli, the CDC’s newly installed Chief of Staff, is said to attend some, but not all, of the meetings. As a Trump appointee and loyalist, he is seen as representing the political leadership of the agency. But he’s also a lawyer with no scientific training or public health experience; he lacks even the faintest technical knowledge needed to understand the content of those meetings. So, despite being the only political appointee at the CDC other than Monarez, nobody seriously believes Buzzelli has now somehow slid into the Acting Director position—nor that he could credibly function in the role, given his limited experience.

Still, some CDC staffers continue to believe Dr. Monarez remains the Acting Director, in part due to a memo* sent out by Matt Buzzelli last week, and because of a CDC leadership website, which continues to list Monarez as Acting Director.

Awkward timing.

This transition to a leaderless agency could not have happened at a more awkward time. By the time thousands of CDC employees were terminated, and dozens of projects had been gutted on April 1, Monarez had been quietly not leading the agency for about a week. So, with restructuring, downsizing, and reorganization on everyone’s mind at the CDC, wheels are spinning, but nothing is happening.

Meanwhile, somewhere, somehow, a small number of DOGE operatives are opaquely working out plans to reinvent the agency. Experts are not being brought into discussions (or at least not very many, and not very often) about the future of the agency, several sources have told me. “It’s more than not knowing,” a CDC source said of DOGE. “There’s no interest.” And even if anyone wanted to listen, there’s nobody officially at the helm within CDC to listen anyway. As the source told me, “Anyone who thinks they have power, doesn't.”

An unprecedented legal situation.

Such a power vacuum at the CDC appears to be unprecedented. Never before has the agency been without either an Acting or permanent Director. The reason for this is that, until now, the Director position has not been a Senate-confirmed one. Now that it is, the Federal Vacancies Reform Act applies, Professor O’Connell said.

The upcoming ACIP vaccine decision is an important test of whether the law is being followed, O’Connell believes, a decision that would have been perfectly fine landing on Susan Monarez’s desk until President Trump nominated her for the permanent position. Now, despite what the CDC’s website and Mr. Buzzelli’s memos say, she can’t make that decision, because she had to drop the formal Acting Director title when she received the permanent nomination, O’Connell pointed out. Of course, she could still try, but it’s unlikely that she will. After all, according to sources, Monarez stopped attending leadership meetings once she was announced as the nominee for the permanent position. This suggests that she is aware of (or has been briefed on) the law, and is taking it seriously.

RFK Jr.’s options.

The Trump administration has a couple of options here vis-a-vis the ACIP recommendations. First, it could simply name a new Acting Director—and it could be anyone other than Susan Monarez. Second, Robert F. Kennedy Jr. could take the decision (normally made by CDC Directors) upon himself. But that might not sit well, especially if he overrides any ACIP recommendations—a rarity, albeit one that has happened in recent memory. (Sidebar: when CDC Director Dr. Rochelle Walensky overrode ACIP on some aspects of Covid-19 booster recommendations, many observers, myself included, questioned the wisdom of that decision, in part because we anticipated that future CDC or HHS leaders might abuse that privilege in far worse ways….)

If Mr. Kennedy wishes to sidestep a potential scandal around this, one seemingly tempting option might be to turf the decision back down to someone else at CDC, like the Chief Medical Officer. That too, would not be lawful, O’Connell said. “If Secretary Kennedy delegates the CDC’s Director’s role in ACIP to someone else (other than himself), that could produce litigation,” she said. A particular section of the Federal Vacancies Reform Act governs this, she noted (Section 3348, for anyone keeping score at home). The upshot is that a task—like rubber-stamping or vetoing ACIP vaccine recommendations—can’t just be relegated if that activity was already assigned to a specific role (like the Director) in the 180-day period leading up to the vacancy. So, if RFK Jr. tried to reassign the task of accepting or rejecting ACIP vaccine recommendations to a different person, it “would be voided by the court—if someone had standing to sue,” O’Connell said.

Finally, even if a new Acting Director were to be installed (or the permanent Director quickly confirmed) the HHS Secretary still has the authority to overturn his or her vaccine policy decisions. And that’s the real problem, isn't it? Regardless of who eventually takes control of the CDC, the long-term tension will not have been resolved, and we may enter uncharted territory. Indeed, while we’ve seen cases of CDC Directors overriding ACIP recommendations, will we soon see the first example of an HHS Secretary overriding an ACIP vote? If so, that would certainly be legal—but likely exceedingly controversial among Senators, even those who voted for RFK Jr.’s confirmation. Unfortunately, their recourse would be minimal. Once confirmed, the Secretary of HHS serves at the pleasure of the President.

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If you have information about any of the unfolding stories we are following, please email me or find me on Signal at InsideMedicine.88.

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*Below is an abridged version of one of two memos sent to CDC staff last week. The memo states who occupies various leadership positions as of April 2, 2025. However, as above, it is legally not possible for Susan Monarez to be Acting CDC Director.

Dear CDC Colleagues,

I would like to express my appreciation to each of the individuals who have been willing to step in to acting director roles on such short notice.

While we are waiting to gain better clarity on the future of each of the centers, we do not want to leave any gaps in CDC’s day-to day functions. These acting positions are for an undetermined amount of time and each center will have its own specific challenges.

Leadership appreciates your flexibility and patience as the consolidation of services evolve.

Once again, thank you to directors who have lent us their staff, and to the new acting directors who have stepped up to the plate. Deb Houry will be connecting with each of the centers this week.

IOD [Immediate Office of the Director]

Acting CDC Director – Susan Monarez

CMO – Deb Houry

COS – Matt Buzzelli

Deputy Director for Public Affairs/Acting OC – Nina Witkofski

Acting OCOO – Sara Patterson (Deb Lubar retiring 4/19)

Senior Advisor – Stuart Burns

….

Sincerely,

Matt Buzzelli

CDC Chief of Staff

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Thanks to Professor Anne Joseph O’Connell, Professor Dorit Reiss, and Professor Steve Vladeck, as well as Dr. Tom Frieden, and the active and RIF’d CDC employees who bravely shared key information that made this post possible.

Thanks to YOU for reading, sharing, speaking out, and supporting Inside Medicine. Please ask your questions in the comments.

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