CDC Declines to Publish Study on COVID-19 Vaccine

‘The study uses a test negative design that will not produce an unbiased estimate of efficacy,’ the agency’s top official said.

Dr. Jay Bhattacharya, director of the National Institutes of Health and the top official at the Centers for Disease Control and Prevention, speaks to a congressional committee in Washington on March 17, 2026. Andrew Harnik/Getty Images

The Centers for Disease Control and Prevention will not publish a study on the effectiveness of COVID-19 vaccination, its top official confirmed late on April 22.

Dr. Jay Bhattacharya, who is serving as the CDC director while the Senate considers President Donald Trump’s nominee for the position, said the paper used a problematic methodology and would thus not be published in the CDC’s quasi-journal, the Morbidity and Mortality Weekly Report (MMWR).