Blumenthal Presses Acting CDC Director on Interference in Publication of COVID-19 Vaccination Report

[WASHINGTON, D.C.] - U.S. Senator Richard Blumenthal (D-CT), Ranking Member of the Senate Permanent Subcommittee on Investigations (PSI), today wrote to Centers for Disease Control & Prevention (CDC) Acting Director Dr. Jay Bhattacharya raising concerns that Dr. Bhattacharya interfered with the publication of a study demonstrating that COVID-19 vaccination significantly reduced the likelihood of hospitalization and emergency room visits during the most recent respiratory virus season. Following reporting in The Washington Post that revealed Dr. Bhattacharya interfered with the publication of the report, Blumenthal slammed the Acting CDC Director for politicizing science and demanded documents and information about the CDC scientific review process.

"Your apparent decision to limit access to critical public health information represents yet another troubling instance of politicized science at the Department of Health and Human Services (HHS) under the Trump Administration," Blumenthal wrote.

"You claimed that publication had been delayed to assess methodological concerns with the study, but the same methodology has been used to measure effectiveness of respiratory virus vaccines for at least 20 years, including in a report on flu vaccine efficacy published just weeks earlier. Recent reports now indicate that HHS has definitively decided that the study will not be published. Given your opposition to public health measures during the coronavirus pandemic, your willingness to entertain discredited theories about the mRNA technology on which COVID-19 vaccines are based, and HHS Secretary Robert F. Kennedy Jr.'s lengthy history of hostility toward vaccination generally, infectious disease researchers are rightly concerned that your explanation for failing to publish the study is little more than a smokescreen," Blumenthal continued.

"Blocking from publication a study that has been approved by career scientists because its findings conflict with the administration's political priorities impedes scientific progress, and will only further weaken Americans' trust in researchers and the scientific process. As you yourself said recently, 'Trust is the foundation of public health, earned through openness, honesty, and guided by the best available evidence,'" Blumenthal concluded.

The full text of Blumenthal's letter is available here and below.

Dear Dr. Bhattacharya:

I write with deep concern regarding reports that you interfered with the publication of a study demonstrating that COVID-19 vaccination significantly reduced the likelihood of hospitalization and emergency room visits ("the study"). Your apparent decision to limit access to critical public health information represents yet another troubling instance of politicized science at the Department of Health and Human Services (HHS) under the Trump Administration.

The study demonstrated that people receiving a COVID-19 vaccination were 50 percent less likely to experience a COVID-19-related emergency room visit, and 55 percent less likely to be hospitalized than those who had not been vaccinated.^[1] At the time it was held back, the study had already cleared the scientific review process of the Centers for Disease Control & Prevention (CDC) for publication in the Morbidity and Mortality Weekly Report (MMWR).^[2] You claimed that publication had been delayed to assess methodological concerns with the study, but the same methodology has been used to measure effectiveness of respiratory virus vaccines for at least 20 years, including in a report on flu vaccine efficacy published just weeks earlier.^[3] Recent reports now indicate that HHS has definitively decided that the study will not be published.^[4] Given your opposition to public health measures during the coronavirus pandemic, your willingness to entertain discredited theories about the mRNA technology on which COVID-19 vaccines are based, and HHS Secretary Robert F. Kennedy Jr.'s lengthy history of hostility toward vaccination generally, infectious disease researchers are rightly concerned that your explanation for failing to publish the study is little more than a smokescreen.^[5]

Your claims about the study are especially hard to credit because of the Trump Administration's relentless politicization of science, particularly when it comes to vaccines.^[6] During President Trump's first week in office, political staff reportedly sought to unilaterally change a CDC scientist's response to a question about the strong connection between cervical cancer prevention and the HPV vaccine.^[7] In May 2025, Secretary Kennedy announced substantial changes to COVID-19 vaccine recommendations, a decision you described as "good science," even though Secretary Kennedy presented no new evidence and apparently failed to consult or even inform CDC scientists of the changes.^[8] In December, when the agency ended its longstanding recommendation for universal vaccination against Hepatitis B at birth, it relied on evidence of the "Burden of Disease" that did not come from its own vaccine experts but rather a contractor with ties to anti-vaccine groups.^[9]

The intent of this overt politicization of science is clear: The Trump Administration wants to hide evidence of the enormous benefits vaccines provide to the American people.^[10] For decades, health officials in the United States have been legally required to assess both the safety and efficacy of vaccines in deciding whether to make them available to the public, and to recommend them as part of the nation's public health guidance.^[11] This is accomplished through rigorous, overlapping systems that monitor a variety of data sources, and teams of scientists who analyze this data and present their findings in publicly accessible journals and meetings.^[12] Blocking from publication a study that has been approved by career scientists because its findings conflict with the administration's political priorities impedes scientific progress, and will only further weaken Americans' trust in researchers and the scientific process. As you yourself said recently, "Trust is the foundation of public health, earned through openness, honesty, and guided by the best available evidence."^[13]

In order for the Permanent Subcommittee on Investigations to understand the Trump Administration's efforts to interfere in the publication of scientific reports, please provide the following information and records by May 7, 2026:^[14]

1. All communications between your office and the CDC staff listed as authors of the study from December 2025 to the present;
2. All drafts of the study that have circulated since it cleared the agency's pre-publication scientific review process;
3. All documents reflecting policies currently in force related to publication in MMWR, including requirements for review or clearance of studies by political appointees;
4. All documents reflecting policies currently in force related to communication of scientific findings with the public, including the authority of political appointees to edit or modify work product of agency scientists;
5. A list of all studies that, since January 20, 2025, have cleared CDC's scientific review process but have yet to be published in MMWR, including:
6. 1. The names of the study's authors;
   2. The date the study cleared pre-publication review;
   3. A description of the study's subject matter;
   4. The names of the official or officials who ordered the study held back;
   5. A detailed description of the reason the study was held back from publication.

Please contact the Subcommittee if you have questions about the procedures for transmitting documents. Thank you for your attention to this request.

Sincerely,

-30-

• Print
• Email
• Share
• Tweet