Sen. Bernie Sanders (I-Vt.) on Thursday released a tranche of Health and Human Services (HHS) emails that appear to show HHS Secretary Robert F. Kennedy Jr. pressuring the Centers for Disease Control and Prevention (CDC) over its vaccine messaging.

Emails indicate that Kennedy directed the CDC’s vaccine advisory panel to restrict access to vaccines, allowed researchers to access “confidential data” to indicate the disproven claim that vaccines cause autism and changed recommendations for the public to receive COVID-19 shots without input from the CDC.

Other emails also show that Kennedy’s then-chief of staff, Matthew Buckham, emailed former CDC Director Susan Monarez in August 2025 about the need for a “political review of major decisions at CDC … to ensure that [the Immediate Office of the Secretary] and the CDC political leadership all have eyes on the decisions for approval/changes before they go into effect.”

Less than a week later, Kennedy fired Monarez “for failing to rubber stamp recommendations from” the CDC’s vaccine panel, the Advisory Committee on Immunization Practices, Sanders said in a statement.

Sanders, the ranking member on the Senate Committee on Health, Education, Labor and Pensions (HELP), blasted Monarez’s firing as “outrageous,” accusing Kennedy of firing her “for her commitment to public health and vaccines.” Sanders requested a bipartisan investigation into her firing and called on Kennedy to resign.

The cache of emails also indicates that Kennedy directed the cancellation of flu vaccine campaigns. A CDC staffer sent an email to her supervisor stating that Andrew Nixon, HHS director of communications, notified her to “pull out of circulation all campaign ad buys related to flu or anything encouraging shots or vaccinations.”

“He said this request came directly from the Secretary,” the staffer wrote. “I noted that these have been paid for and are in flight and he acknowledged and asked that we work right away on things that are on social/online, magazines, and then will eventually need to do items that may be on bus stops or benches (if it includes those type of things).”

A separate email issued by Nixon and released by Sanders insisted that the request “was a direct ask from Secretary Kennedy.”

Sanders said that Dr. Debra Houry, former CDC chief medical officer, gave the emails to the committee.

The Hill has reached out to HHS for comment.

Sanders has called for HELP committee chair Sen. Bill Cassidy (R-La.) to schedule a hearing against Kennedy’s vaccine claims, as the secretary had a long history as an anti-vaccine activist before President Trump nominated him for HHS. The Vermont senator accused Kennedy of running a “dangerous misinformation campaign” as the head of HHS.

“The reality is that since Secretary Kennedy has been in office, he has continued his longstanding crusade against vaccines and his advocacy of conspiracy theories that vaccines cause autism — all of which have been repeatedly rejected by scientists,” Sanders wrote in his letter to Cassidy in April.