A completed CDC study showing Covid-19 vaccines cut hospitalisations and emergency department visits among healthy adults by roughly half has been blocked from publication in the agency's flagship scientific journal, according to three people with direct knowledge of the decision.
The report had cleared the CDC's full internal scientific-review process, which involves dozens of scientists, and had been scheduled for publication on 19 March 2026 in the Morbidity and Mortality Weekly Report (MMWR), the journal American public health officials have relied upon for more than 70 years. Instead, acting CDC director Jay Bhattacharya first delayed it and, as of 22 April 2026, a formal rejection letter had been issued to the report's authors.
