Democrats Demand Answers on Trump Administration’s Suppression of COVID-19 Vaccine Efficacy Data

Energy and Commerce Committee Democratic leaders wrote to Department of Health and Human Services (HHS) Secretary Robert F. Kennedy, Jr. today demanding answers about a decision by Dr. Jay Bhattacharya, the most senior political official at the Centers for Disease Control and Prevention (CDC), to suppress a study showing that COVID-19 vaccines cut hospitalizations by roughly half during the 2025-2026 winter season. The letter follows new reporting out this week that the Food and Drug Administration (FDA) blocked publication of research finding COVID-19 and Shingles vaccines are safe and effective. 

The letter was signed by Full Committee Ranking Member Frank Pallone, Jr. (D-NJ), Health Subcommittee Ranking Member Diana DeGette (D-CO), and Oversight and Investigations Subcommittee Ranking Member Yvette D. Clarke (D-NY).

“Dr. Bhattacharya’s refusal to publish this study appears to be a deliberate effort to suppress evidence of vaccine effectiveness by your hand-selected ideological ally,” the Democratic Committee leaders wrote. “Dr. Bhattacharya’s latest actions reinforce a disturbing year-long pattern of the Trump Administration’s Department of Health and Human Services obstructing the flow of scientific information that helps to keep Americans healthy.”

The study, Interim Effectiveness of 2025-2026 COVID-19 Vaccines in Adults, was originally scheduled for publication in CDC's Morbidity and Mortality Weekly Report (MMWR) on March 19, 2026. It found the COVID-19 vaccine reduced emergency department visits, urgent care visits, and hospitalizations among healthy adults by approximately 50 percent. Despite clearing CDC's rigorous internal scientific review process, Bhattacharya — who serves as National Institutes of Health (NIH) Director and currently oversees CDC — reportedly delayed the study's publication, and it was later pulled entirely.

The letter documents a broader pattern of the Trump Administration obstructing the flow of public health information. On January 21, 2025, HHS ordered federal health agencies to pause all external communications and directed staff to refrain from issuing anything without approval from a presidential appointee. MMWR — which had published uninterrupted for 65 years — missed two consecutive issues. CDC subsequently removed public health information about mpox prevention, HIV, and mental health from its website, a move a federal district court later ruled lacked any reasoned scientific basis and jeopardized access to treatment for life-threatening conditions. 

The Democrats also raised alarm about HHS simultaneously amplifying unfounded anti-vaccine claims. In November 2025, CDC published a webpage that parsed prior studies to cast doubt on the scientific consensus that vaccines do not cause autism, while omitting their well-established role preventing disease, hospitalization and death. Shortly after, then-FDA Center for Biologics Director Dr. Vinay Prasad issued a memo proposing onerous new vaccine approval standards based on unverified data — while ignoring evidence that COVID-19 vaccination likely averted more than 2.5 million deaths globally between 2020 and 2024.

“Because of the ways your actions deliberately misrepresent the risk of vaccinations, many Americans may needlessly forgo immunization, and as a result get sick, hospitalized, or die,” the Democrats continued. “Dr. Bhattacharya’s suppression of the Interim Effectiveness study has the potential to expose Americans to further death and disease.”  

The Committee leaders requested responses from Secretary Kennedy to a series of questions, including: 

• Whether any HHS political appointee has directed the delay, suppression, or editing of any MMWR manuscript since January 20, 2025;
• How many manuscripts have been rejected after clearing full scientific review over the past decade; and
• Who made the final decision to pull the Interim Effectiveness study entirely. 

Read the full letter HERE. 

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