Outrage of the Month: Censorship of CDC and FDA Vaccine Studies
Health Letter, June 2026
By Robert Steinbrook, M.D.
Director, Public Citizen's Health Research Group
If you’re not outraged, you’re not paying attention!
Read what Public Citizen has to say about the biggest blunders and outrageous offenses in the world of public health, published monthly in Health Letter.
The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) are science-based federal agencies that should promote medical research, not censor studies because their findings undermine Health and Human Services (HHS) Secretary Robert F. Kennedy Jr.’s anti-vaccine agenda.
In recent months, however, both the CDC and FDA have blocked publication of studies supporting widely used vaccines against COVID-19 and shingles (herpes zoster). Suppressing scientific research exposes the nonsense of Kennedy’s frequently repeated claims that he would bring “gold standard” science and “radical transparency” to the nation’s public health agencies.
In April 2026, the acting director of the CDC blocked publication of a COVID-19 vaccine effectiveness study in the Morbidity and Mortality Weekly Report (MMWR), the agency’s leading scientific journal. The report, which had been scheduled for publication in March, showed that the 2025-2026 vaccines were about 50% effective during the first months after vaccination in preventing hospitalizations as well as emergency department and urgent care visits among adults who were not immunocompromised (September-December 2025).
Dr. Jay Bhattacharya, director of the National Institutes of Health and earlier this year the acting CDC Director, disputed the characterization of his actions as “blocking” publication in the MMWR, stating instead that he “raised specific concerns about the statistical methodology chosen for the study in question.” In fact, the methodology has been widely used in peer-reviewed publications on COVID-19 vaccine effectiveness and was also used in a December 2025 report in the MMWR about COVID-19 vaccine effectiveness in children.
Ironically, the censored report is available online. By censoring the research, the CDC likely focused more attention on it than it would have otherwise received.
Separately, the FDA blocked publication of studies supporting widely used vaccines against COVID-19 and shingles. In October 2025, FDA scientists were told to withdraw two vaccine safety studies about the 2023-2024 COVID-19 vaccines that had already been accepted for publication in medical journals. One study, which looked at safety monitoring of vaccination among commercial health plan enrollees ages 6 months to 64 years and was presented at a medical meeting in August 2025, found “no new safety concerns.” The other, which examined vaccine safety among Medicare beneficiaries aged 65 years and older, is available online as a preprint, an earlier version that has not undergone peer review. The study found “no new safety signals” as well as “a potential, but rare, elevation in anaphylaxis” risk (a severe, potentially life-threatening allergic reaction) associated with one of the vaccines.
In defending the withdrawal of the COVID-19 vaccine safety studies, a HHS spokesperson told The New York Times: “The studies were withdrawn because the authors drew broad conclusions that were not supported by the underlying data.” The comment reflected a misunderstanding of how peer-reviewed medical journals work. From my work as an editor at the New England Journal of Medicine and JAMA Internal Medicine, I know that journal editors routinely work with authors to revise manuscripts and to ensure that the conclusions follow from the data. I did that all the time.
Abstracts of the shingles vaccine studies, one about the safety of the Shingrix vaccine and one about the effectiveness of the same vaccine, were scheduled for submission to a drug safety conference. The Shingrix vaccine, first approved by the FDA in 2017, is used for prevention of shingles in adults aged 50 years and older and in adults aged 18 years and older at increased risk due to immunodeficiency or immunosuppression.
The Senate will hold confirmation hearings for the vacant positions of FDA commissioner and CDC director. The nominees must commit to reversing the decisions to block the studies and to allowing their prompt publication. The nominees must assure the American people that, if confirmed, the agencies they will lead will no longer censor the publication of scientific research. Bona fide public health agencies do not censor bona fide vaccine research.