CDC Delays COVID Vaccine Effectiveness Report

Acting CDC Director Jay Bhattacharya has delayed publication of a report showing the 2025-2026 COVID-19 vaccine reduced emergency department visits by 50% and hospitalizations by 55% among healthy adults during the past winter season. The suppression of the findings has sparked accusations of political interference in public health science.

What the Report Found

The study, which had cleared the CDC's scientific review process and was scheduled for publication on March 19 in the Morbidity and Mortality Weekly Report (MMWR), found significant vaccine effectiveness. Between September and December, healthy adults who received the updated COVID vaccine were half as likely to visit emergency departments and urgent care facilities, and 55% less likely to be hospitalized for COVID-related illness, compared with unvaccinated individuals.

The Methodology Dispute

Bhattacharya cited concerns about the observational method used to calculate vaccine effectiveness -- specifically the "test-negative design" approach. This methodology examines people who are already sick enough to seek care, tests them, and then compares vaccination rates between those who test positive and those who do not. However, the same methodology has been a cornerstone of CDC vaccine evaluation for decades. A flu vaccine effectiveness report using the identical methodology was published in the MMWR just one week before the COVID report was pulled.

Political Interference Concerns

Current and former CDC officials have raised alarms that the delay aligns with the views of Health Secretary Robert F. Kennedy Jr., a longtime vocal critic of vaccines. Critics argue that information about the vaccine's benefits is being suppressed precisely because it contradicts the administration's skeptical stance on COVID-19 vaccination. The move represents what many health experts consider an unprecedented level of political intervention in the agency's scientific publishing process.

Why It Matters

The delayed publication raises fundamental questions about the independence of public health agencies from political influence. Timely and transparent sharing of vaccine effectiveness data is critical for healthcare providers making recommendations and for individuals making informed decisions about their health during ongoing respiratory virus seasons.