Susan Monarez hearing: Former CDC director says RFK Jr. pressured her to rubber-stamp vaccine approvals

Cassidy just gaveled out the hearing, ending Monarez and Houry's testimony for the day.

Sen. Andy Kim, D-N.J., raised concerns about the CDC under Secretary Kennedy’s leadership twisting data to fit a predetermined conclusion. Houry said she was also concerned that the science coming out of the CDC won’t be “gold standard.” 

While she was at the CDC, Houry said, HHS’ deputy policy chief of staff met with her and three other high-ranking CDC officials (all of whom have subsequently resigned) about handing over confidential data to David Geier, a discredited researcher who has repeatedly claimed that vaccines cause autism.

“For two days, she sat with us and asked us to grant access to a data that has privacy and security concerns to this researcher,” Houry said.

Kennedy has said he brought on Geier as a contractor. NBC News previously reported that Geier was tasked with analyzing vaccine safety data.

Cassidy said that Mullin has now informed reporters that he was "mistaken" about the meeting between Monarez and Kennedy being recorded.

"It's just been reported that Sen. Mullin told reporters that he was mistaken in saying that the RFK-Monarez meeting was recorded," Cassidy said.

"But in case he's mistaken that he was mistaken, if there is a recording, it should be released, and it would beg the question of what other conversations were recorded," Cassidy said.

An HHS spokesperson told NBC News of Mullin's comments: "This was incorrectly stated at the hearing. There is no recording."

The spokesperson added that "Susan Monarez was tasked with restoring the CDC to its core mission after decades of bureaucratic inertia, politicized science, and mission creep eroded its purpose and squandered public trust—and she refused to do it, and the President fired her."

Sen. Mullin backtracks on claim of recorded meeting between Kennedy and Monarez

02:15

As she was taking questions from Sen. Andy Kim, D-N.J., Monarez said that Kennedy planned to change the childhood vaccine schedule as soon as this month.

"When you were talking to secretary, he was basically telling you that the child vaccine schedule will change in September. Is that roughly right?" Kim asked.

"That is correct," Monarez answered.

Her comments come just one day before the CDC's vaccine advisory committee is set to meet.

Speaking as a hepatologist, or liver specialist, Cassidy explained why some infants can be infected with hepatitis B or other sexually transmitted diseases at birth and go on to develop chronic, lifelong infections.

In the decade after the hepatitis B vaccine was approved for newborns, he said, infections among newborns declined by 68%. Today, he said, fewer than 20 babies per year get hepatitis B from their mother.

“That is an accomplishment to make America healthy again, and we should stand up and salute the people that made that decision, because there’s people who would otherwise be dead if those mothers were not given that option to have their child vaccinated,” Cassidy said.

After Sen. Markwayne Mullin suggested that the meeting between Monarez and Kennedy ahead of her firing was recorded, Cassidy said that the committee had a right to see the records.

"I will note that if materials have been provided to Sen. Mullin and invoked in official committee business, they're committee records, and all other senators on the committee have the right to see those records," Cassidy said.

He added, "I’ll also note that if he has it, I’m also curious why only one senator was given this, and why we’re just hearing about it now, and why didn’t the secretary share it at the Senate Finance Committee" hearing.

He called on HHS to release a recording, if it had one.

"I'd also like to know why it was recorded, but releasing the recording would be radical transparency, and this is about fulfilling the president's vision of radical transparency," Cassidy said.

NBC News has reached out to Mullin, HHS and lawyers for the witnesses.

Just weeks after voting against Monarez's confirmation on the floor of the Senate, Democrats on the committee are now heaping praise on her and Houry.

First, Sen. Tim Kaine, D-Va., apologized to Monarez for voting against her, saying, "I had concern about your backbone, and I was wrong, and I apologize to you for being wrong. I think it’s important when you’re wrong to admit you’re wrong."

Later, Sen. Ed Markey, D-Mass., who also voted against Monarez's confirmation, told her and Houry, "I want to thank you for being public health heroes."

"When you took your positions, you swore an oath to public health and safety, not to political ideology, and you kept that promise to the American people. When confronted with pressure to make decisions based on political science, you chose real science," he added.

Meanwhile, many of the Republicans who voted to confirm her are criticizing her now.

Sen. Tim Kaine, D-Va., asked Houry whether she or a career scientist ever briefed Kennedy about recent measles outbreaks.

"We did not brief Secretary Kennedy," she responded.

She echoed Kaine's concern about health funding, noting that most CDC funding goes toward state and local communities.

"As we see budget cuts to CDC, your community will see that too," she said.

From his official X account, Kennedy thanked Sen. Rand Paul, R-Ky., who grilled Monarez about the safety and effectiveness of Covid vaccines. 

Paul said ahead of the hearing that he would defend Kennedy and called on other committee members to do the same.

Kennedy also reacted to a video in which Sen. Roger Marshall, R-Kan., called the CDC “the cause of vaccine hesitancy” and told Monarez “you are the problem.” 

“Thank you, @RogerMarshallMD. We will earn back Americans’ trust and refocus the CDC on its core mission,” Kennedy wrote on X.

Sen. Tim Kaine, D-Va., opened his questioning by apologizing to Monarez. He said he did not question her qualifications for leading the CDC but whether she had the "backbone" for the job, considering the political climate and concerns about Kennedy's plans.

Kaine noted that he did not vote for her confirmation.

"I had concern about your backbone, and I was wrong," he said. "And I apologize to you for being wrong. I think it's important when you're wrong to admit you're wrong."

Houry told Sen. Lisa Blunt Rochester, D-Del., that she and Monarez were transparent during their tenure at CDC about possible conflicts of interest on the CDC’s independent vaccine advisory committee.

“We posted conflicts of interest for the past two decades of the ACIP members to really embrace what the president had said around radical transparency and to dispel the conflicts of interest,” Houry said.

“If you had significant biases or conflicts of interest, you weren’t included on ACIP,” she added.

Kennedy has accused the vaccine advisory committee of being laden with conflicts and used that concern as justification for firing and replacing the panel’s previous members. (Many of the new members have expressed skepticism about vaccines.)

Sen. Lisa Murkowski, R-Alaska, said she was "concerned" about when career scientists are "excluded."

Asked about career scientists being excluded from the director' office, Houry said that almost everyone who is left is political, rather than a career scientist.

"There must be somebody that is providing that career science, then," Murkowski said.

"A level down we do have center directors, although 80% are now acting because they've been fired, resigned or retired," Houry said.

Sanders added to Cassidy's backing of Monarez and Houry in response to Moody's questions.

"I find it rather astounding that anyone is concerned that government heads of agencies talk to the elected officials of the United States of America," he said. "That is what they are supposed to do." 

Sen. Bernie Sanders, I-Vt., speaks at the hearing today. Kevin Dietsch / Getty Images

After Sen. Ashley Moody, R-Fla., took issue with Monarez's decision to reach out to Cassidy after her firing, Cassidy took a moment to explain the communication between him and Monarez.

"I just want to make a brief comment as my name was invoked," Cassidy said. "As the chairman of the committee with jurisdiction over the CDC that favorably reported Dr. Monarez as the CDC director, it is entirely appropriate for someone with oversight concerns to contact my office, or me, or frankly, any of us."

"Upon receiving outreach from Dr. Monarez, I contacted both the secretary [of health and human services] and the White House to inquire what was happening and to express concerns about what was alleged. As soon as the director was fired, the HELP Committee began reviewing the situation," Cassidy added.

Sen. Ashley Moody, R-Fla., asked Monarez whether she coordinated with Houry or other colleagues "surrounding your leaving."

"I did not coordinate with anyone surrounding my leaving," Monarez said. "I was terminated abruptly."

GOP Sens. Jim Banks, R-Idaho, and Ashley Moody, R-Fla., have each pressed Monarez about why she chose the attorneys that she did.

Her lawers, Mark Zaid and Abbe Lowell, have represented clients who have spoken out against the Trump administration in the past. Lowell also represented Hunter Biden, former President Joe Biden's son, when he faced federal charges on gun possession last year.

"I'm just noticing that they're aiding with your testimony. They keep handing you notes and whispering in your ears. So I figured you should probably for the record, put their names in the record," Moody told Monarez, who initially declined to name her lawyers.

Moody also referred to the two attorneys as "anti-Trump," telling Cassidy, "I would like the record to reflect that you have called a hearing of two people who have hired anti-Trump lawyers."

Asked what keeps them up at night, Monarez and Houry both expressed fears for the future of public health in the country.

"The next outbreak, and I don't believe that we'll be prepared," Monarez said.

Houry said she was "concerned about the future of CDC and public health in our country."

"Given what I have seen, if we continue down this path, we are not prepared, not just for pandemics, but for preventing chronic health disease, and we're going to see kids dying of vaccine-preventable diseases," she added.

Asked about Kennedy's assertion that "everybody" would be able to get Covid vaccines, Houry said that her mother had trouble getting one.

"My mom lives in Virginia, and she was unable to get it," Houry said.

Cassidy entered a new story from The Washington Post into the record for the hearing.

The Washington Post reported that a top HHS official emailed Monarez, saying he "wanted to elevate the absolute need for political review of major policy decisions at CDC."

The email, which has not been independently verified by NBC News, was reportedly written by HHS chief of staff Matthew Buckham, according to the report.

Cassidy at the hearing today. Kevin Dietsch / Getty Images

In response to questions from Sen. Chris Murphy, D-Conn., Houry says that following the shooting at the CDC some staffers are removing their names from their work.

"I have many that won't speak about vaccines now and remove their names off of papers," she said. "They don't wish to present publicly anymore because they feel they were personally targeted because of misinformation."

"Even at the ACIP meeting, you'll notice we don't have our subject matter experts presenting anymore," Houry added. "It's taken up to a leadership level because we did that to protect our staff and scientists so that they would be disconnected and their names not associated, so that they won't be targeted."

In a heated meeting with Kennedy last month, Monarez said, the secretary made assertions that were “particularly hurtful and disparaging.”

Monarez said Kennedy told her that the CDC was “the most corrupt federal agency in the world” and that its employees were “horrible people.”

“He said that CDC employees were killing children and they don’t care,” Monarez continued. “He said that CDC employees were bought by the pharmaceutical industry. He said CDC forced people to wear masks and social distance like a dictatorship.”

Kennedy’s most hurtful claim, Monarez said, was that “during the Covid outbreak, CDC told hospitals to turn away sick Covid patients until they had blue lips before allowing them to get treatment.”

At the start of the pandemic, before vaccines were developed or distributed, hospitals were overwhelmed with Covid patients and had to prioritize those who were sickest.

Monarez testified to Sen. Maggie Hassan, D-N.H., that Kennedy was "very upset" when she told him she wouldn't pre-emptively approve vaccine recommendations from a key advisory panel.

"He was very upset," she said. "The entire meeting was very tense. He was very upset throughout the entirety of our discussion, and it was not a productive exchange of information."

Asked what directive Monarez received that would have violated her oath of office, Monarez referred to concerns over compromising the CDC's scientific integrity.

"It was actually the latter part that concerned me, 'well and dutifully execute the functions of the office,' and being asked to compromise scientific integrity associated with those decisions and to fire individuals without cause gave me pause about that particular phrase," Monarez said.

Sen. Marshall: 'I think the CDC is the cause of vaccine hesitancy'

01:27

In response to a question from Sen. Roger Marshall, R-Kan., Monarez said the CDC’s role is to give vaccine recommendations, not mandates.

“What CDC does is provide the evidence associated with the recommendations so that a parent and a physician can make the best determination for them,” Monarez said.

When it comes to the CDC’s childhood immunization schedule, she added, “every parent should have the opportunity to talk to their pediatrician and make sure that they understand the benefits and the risks of those vaccines and what is in the best interest of their children.”

Sen. Roger Marshall, R-Kan., got into a combative exchange with Monarez about vaccines, the Covid pandemic and her leadership.

"Would you agree that that certainly you’re going in a different direction philosophically than Secretary Kennedy is?" he said.

She responded, "If I am put in a position of having to say, ‘I will cede the scientific integrity to retain my job,’ then I am not the right person for the position."

Houry delivered a stark message about what an increase in vaccine-preventable diseases could mean for Americans.

"It's going to be heartbreaking," Houry told Sen. Tammy Baldwin, D-Wis.

Houry continued, noting that the diseases have "long-term consequences."

"In the U.S., we have gone so far in reversing this," she said. "We don't want our children to die."

Former CDC Chief Medical Officer Dr. Debra Houry testifies today. Kevin Dietsch / Getty Images

Sen. Tammy Baldwin, D-Wis., asked Houry if the then-chief medical officer ever briefed Kennedy.

"You know, we would have loved to have had the conversations with him. I offered to two different HHS leaders that we would like to brief the secretary," Houry testified.

"He never received that, and many times I would send emails to our leadership team to share with HHS when he did say things that weren’t scientifically correct, so that we could help support him. But we again, our requests were not received to brief him," she added.

Monarez recalled Kennedy telling her to no longer speak with members of Congress after she informed lawmakers about a meeting that concerned her.

"He was very concerned that I had spoken to members of Congress, and he told me I was never to do it again," Monarez said of Kennedy.

Ask by Sen. Susan Collins, R-Maine, about how the HHS response to this year's measles outbreak differed from its response to previous outbreaks, Houry said she did not brief Kennedy and had to correct misinformation from him.

"First, I never briefed the secretary, as did the center director who oversaw measles, never briefed the secretary, and an outbreak response usually you would be briefing leadership," she said.

"The second thing is, he said things like vaccines had fetal parts, and I had to send a note to our leadership team to correct that misinformation," Houry added.

Sen. Rand Paul, R-Ky., asked Monarez whether Covid vaccines reduced transmission, denying that they did — a common talking point among those skeptical of the shots. Paul has repeatedly questioned the safety and effectiveness of Covid vaccines.

Monarez said that “the Covid vaccine can reduce viral load in individuals,” adding that “when you have reduced viral load, you will have reduced transmission.” Studies have shown that to be the case, though the impact on transmission has been lower since the omicron variant became dominant in late 2021.

Paul responded that people can still transmit Covid if they've been vaccinated against it (which isn't the same as the vaccine not reducing transmission at all).

Collins questions Monarez about Kennedy pushing her to approve vaccine recommendations

01:57

Sen. Susan Collins, R-Maine, asked whether Kennedy consulted with Monarez on new vaccine committee members.

She said he did not.

Asked for the public health implications if health decisions are made by political staff, Monarez said, "It concerns me."

"These are important and highly technical discussions that have lifesaving implications," Monarez said.

Monarez and Houry each testified that they had never seen any evidence to back the CDC's shifting guidance on Covid vaccines for healthy kids and pregnant women.

"We have not seen the data yet. In fact, after the tweet came out, we asked for a written memo from HHS because I couldn’t implement guidance off of a tweet," Houry told Sen. Patty Murray, D-Wash., referring to Kennedy's May tweet changing Covid vaccine recommendations.

Murray reiterated in her next question, "You can’t provide guidance off of a tweet?"

"I didn’t think that was prudent," Houry answered.

Sen. Rand Paul, R-Ky., was combative and criticized the doctors' responses about how the Covid vaccine benefits public health.

After a witness said that the Covid vaccine "can" reduce the rate of death for children, Paul scoffed.

"Once again, 'it can.' That's a ridiculous answer," he said.

Paul cut off Monarez during her response to a question about people she refused to fire, prompting Sanders to ask him to let her answer the question.

Monarez told Cassidy that she and Kennedy “got into an exchange,” where she expressed willingness to change the childhood vaccine schedule if there were science or evidence supporting such a change.

“He responded that there was no science or evidence associated with the childhood vaccine schedule,” Monarez added.

“To be clear, he said there was no science or data, but that he still expected you to change the schedule?” Cassidy asked after Monarez concluded her recollection.

“Correct,” Monarez responded.

Asked by Sen. Patty Murry, D-Wash., if they had seen any evidence for changing the childhood vaccine schedule, both Monarez and Houry said they had not.

"I was certainly open if there were scientific data sets or evidence associated with anything that would help keep our children safe. I was open to seeing it. I have not seen that data," Monarez said.

Houry concurred: "Ditto. We've asked for the data and asked for the modeling to support any decision that is done."

Sanders referenced Kennedy's comments at a hearing earlier this month, when the HHS secretary rejected Monarez's account of her termination. At the time, Kennedy responded "yes" when asked if he believed she was lying.

"Dr. Monarez, at a Sept. 4 hearing in the Finance Committee, Secretary Kennedy called you a liar for stating that you were fired because you refused to preapprove vaccine recommendations," Sanders said. "Is that accurate? Are you a liar?"

"That is not accurate," Monarez responded.

During Cassidy's questioning time, he asked Monarez about whether Kennedy ever spoke to the president about changing the childhood vaccine schedule.

"He did say that he had spoken to the president," Monarez said, describing a meeting she had with Kennedy. "He spoke to the president every day about changing the childhood vaccine schedule."

Monarez added that she and Kennedy "got into an exchange," where she expressed willingness to change the childhood vaccine schedule if there were science or evidence supporting such a change.

Monarez tells Cassidy that Kennedy asked her to meet with lawyer Aaron Siri as part of a line of questioning about changes to the childhood vaccine schedule.

Siri has advocated for the FDA to revoke approval of the polio vaccine.

In her opening remarks, Houry, who resigned after Monarez's firing, said that Health Secretary Robert F. Kennedy Jr. "censored CDC science, politicized its processes and stripped leaders of independence."

Houry spoke at length about how honored she was to work in multiple roles at the CDC over several years, but said, "I could not in good conscience remain under those conditions," referring to Kennedy's agenda.

Houry also described Kennedy's decision to replace the members of a CDC vaccine advisory panel with vaccine skeptics, telling senators that the new committee members and Kennedy "spread misinformation and promoted unproven treatments."

She also accused Kennedy of weakening response readiness to infectious disease outbreaks, saying that a decline in Covid and flu monitoring is "leaving us with far less visibility into what's coming."

Near the end of her testimony, Houry added, "Due to the secretary’s actions, our nation is on track to see drastic increases in preventable diseases and declines in health."

"My goal today is to provide real examples of the damage CDC is experiencing and to offer constructive steps squarely within Congress’ responsibilities," she added.

Monarez: Kennedy 'wanted blanket approval' for vaccine recommendations

03:13

Monarez said she refused to approve vaccine recommendations without evidence or fire career officials without cause, but "was never misaligned with the administration priorities."

She said she shared Kennedy's publicly stated goals of "protecting the public from threats, building infrastructure, modernizing systems, investing in the workforce and enhancing scientific rigor" and remains supportive of them.

"The question is whether they can be achieved without the expertise required at CDC," she said.

"Regarding trustworthiness, I cannot define that word for Secretary Kennedy," Monarez added. (Kennedy told Sen. Elizabeth Warren, D-Mass., at a Senate hearing earlier this month that he asked Monarez whether she was a “trustworthy person” and she said no.)

Monarez gave her account of the conversation today: “I told the secretary that if he believed he could not trust me, he could fire me.”

Cassidy and Sen. Susan Collins, R-Maine, suggested swearing in Monarez and Houry before they begin answering questions from lawmakers.

Sanders objected, noting that lawmakers did not swear in Kennedy before his testimony. Collins suggested swearing in today's witnesses as well as future HHS witnesses, noting that it might make the witnesses seem more credible, but Sanders objected again by saying it was an unfair double standard.

"I will note that it's against the law to lie to Congress anyway," Cassidy said.

"That's right," Sanders responded, prompting laughter in the hearing room.

It's relatively rare for witnesses to be charged with lying to Congress. Michael Cohen, Trump's former attorney turned critic, was previously charged with the crime.

Pushing back on the idea that U.S. health has been on a stark decline, as Kennedy regularly states, Houry noted that life expectancy in the U.S. has nearly doubled over the last 150 years.

"We got there through vaccinations, through safer food and water, through smoking cessation and through the quiet, steady work of public health and every state and county across the country," she said.

Monarez concluded her opening remarks with a warning about the future of public health and the country's path forward.

"The question before us is whether we will keep faith with our children and grandchildren — ensuring they remain safe from the diseases we fought so hard to defeat: polio, measles, diphtheria, whooping cough and many others," Monarez said.

"Undoing that progress would not only be reckless — it would betray every family that trusts us to protect their health," she concluded.

Cassidy noted that Monarez was the first CDC director to go through a Senate confirmation hearing (a new requirement under a 2023 law). Cassidy said Republicans supported that process and overwhelmingly voted to confirm her, so her firing should raise questions about why the tide changed so quickly.

“If someone is fired 29 days after every Republican votes for her, the Senate confirms her, the secretary said in her swearing-in that she has, quote, unimpeachable scientific credentials and the president called her an incredible mother and dedicated public servant — what happened? Did we fail? Was there something we should have done differently?” Cassidy said.

“It may be that we did nothing wrong, in which case, Dr. Monarez and Dr. Houry, the onus is upon you to prove that the criticisms leveled by the secretary are not true,” he added.

'What happened? Did we fail?': Sen. Cassidy questions firing of CDC director

05:35

Monarez laid out Kennedy's demands that she said "were inconsistent with my oath of office and the ethics required of a public official" and ultimately led to her termination.

She said that Kennedy directed her to commit to approving every recommendation "regardless of the scientific evidence" from the CDC's Advisory Committee on Immunization Practices, which Kennedy gutted before adding vaccine skeptics. Kennedy also directed her to "dismiss career officials responsible for vaccine policy, without cause," she said.

"He said if I was unwilling to do both, I should resign," she said. "I responded that I could not pre-approve recommendations without reviewing the evidence, and I had no basis to fire scientific experts."

"He told me he had already spoken with the White House several times about having me removed," she added.

Days before her firing, Monarez described being told to travel to D.C. "immediately," which would have forced her to miss the funeral of the officer who was killed responding to the shooting at the CDC. Missing the memorial, Monarez said, was something she "was not willing to do."

Monarez also emphasized during her testimony that the hearing "should not be about me."

"Today should be about the future of trust in public health," she said.

Former CDC director details RFK Jr.’s demands before she was fired

09:00

Sanders: Monarez was fired for refusing to be a 'rubber stamp' for Kennedy

06:20

Sen. Bernie Sanders, I-Vt., the committee's ranking member, questioned how Kennedy's prior praise for Monarez quickly morphed into criticism, leading to her termination shortly after she was confirmed to the job.

"Dr. Monarez was fired because she refused to act as a rubber stamp to implement Secretary Kennedy's dangerous agenda to substantially limit the use of safe and effective vaccines that would endanger the lives of the American people and people throughout the world," Sanders said.

Sanders said that one reason Monarez was fired was that she "refused to get rid of career scientists for doing their jobs."

But, taking aim at Kennedy, Sanders added, "The issue is deeper than that, It is about Secretary Kennedy’s dangerous war on science, public health and the truth itself."

Today's hearing featuring Monarez's testimony has kicked off.

The top Republican and Democrat will deliver opening statements, as will Monarez and Houry, before senators can ask the witnesses questions.

Monarez prepares to testify today. Kevin Dietsch / Getty Images

Polling showing that a majority of President Donald Trump’s voters support vaccines was shared with several Republicans lawmakers’ staffers in a closed-door meeting earlier this month, according to two people familiar with the meeting.

NBC News obtained a copy of a memo, dated Aug. 26, summarizing the poll results. It was conducted by veteran Republican pollsters Tony Fabrizio and Bob Ward and concluded “that there is broad unity across party lines supporting vaccines such as measles (MMR), shingles, tetanus, diphtheria and pertussis (TDAP), and Hepatitis B.” Fabrizio and Ward presented the findings during the meeting, the sources said.

In an email to NBC News, Ward confirmed the memo was authentic but declined to comment about the meeting. It’s unclear who commissioned the poll or arranged the meeting. A source close to the White House denied that the administration requested the poll.

The poll results may explain the shift in tone from some GOP senators at Kennedy's hearing earlier this month.

Read the full story here.

As chairman, Cassidy called today's hearing after Monarez's firing, saying in a statement that "Americans need to know what has happened and is happening at the CDC."

"They need to be reassured that their child’s health is given priority. Radical transparency is the only way to do that," he said.

Cassidy, a doctor, has been a prominent Republican voice expressing concerns about the Trump administration's handling of health issues.

Sen. Rand Paul, R-Ky., who sits on the HELP committee, posted the following statement yesterday, urging Republicans to defend Kennedy during the hearing.

“My friend and ally @SecKennedy will be under attack from the establishment of both parties at the Senate HELP hearing tomorrow. I will defend him. Ask you Senator and Senate GOP HELPS members to do the same.”

Though Kennedy will not be at the hearing, senators will have the opportunity to ask Monarez about her firing and conditions at the CDC. The health secretary came under fire from Democrats for Monarez’s firing and faced bipartisan criticism for his vaccine policies at a Senate Finance hearing two weeks ago. 

Houry will testify today about what led to her decision to resign after Monarez's firing.

According to her prepared remarks obtained by NBC News, Houry will tell the Senate committee that Kennedy’s actions have “led to a cascade of decisions which have significantly weakened and undermined CDC’s ability to do its job protecting the health of Americans.”

Houry will tell lawmakers she resigned because Kennedy "repeatedly censored CDC science, politicized our processes, and stripped agency leaders of the ability to protect the health of the American people."

Access to childhood vaccines faces a “real risk” in the United States, Susan Monarez is expected to tell a Senate health committee today.

The testimony by Monarez, who was fired as director of the Centers for Disease Control and Prevention by Health Secretary Robert F. Kennedy Jr. in August, comes just a day before the agency’s influential vaccine panel plans to vote on whether to delay or restrict access to shots that protect children against potentially serious contagious diseases.

“The stakes are not theoretical,” Monarez said in prepared testimony to the Senate Committee on Health, Education, Labor and Pensions obtained by NBC News. “We have already seen the largest measles outbreak in more than 30 years, which claimed the lives of two children. If vaccine protections are weakened, preventable diseases will return.”

Read the full story here.