The U.S. Centers for Disease Control and Prevention delayed publishing a report showing the benefits of the Covid vaccine, according to a new report.
The stalled publication has sparked concerns that information conflicting with the views of Health and Human Services Secretary Robert F. Kennedy Jr. — a longtime vaccine skeptic — may be sidelined. The CDC, however, insists the move followed standard procedure.
The new report found that healthy adults who received the Covid vaccine cut their risk of urgent care and emergency visits by 50 percent, and Covid-related hospitalizations by 55 percent, compared to adults who did not receive a dose in 2025 or 2026, according to The Washington Post.
The research was due to be published March 19 in the Morbidity and Mortality Weekly Report, the CDC’s premier scientific journal.
The study had been green-lit by the CDC’s scientific review process but acting CDC Director Jay Bhattacharya delayed the report over methodological concerns, two unnamed scientists familiar with the matter told the outlet.
The postponement occurred despite the CDC’s long history of using the same methodology to assess respiratory virus vaccines, including flu shots. Those methods also underpinned a 2021 New England Journal of Medicine study on Covid vaccine effectiveness.
The Independent has asked the CDC and HHS for comment.
Andrew Nixon, a spokesperson for HHS which oversees the CDC, said the acting director’s delay was not unusual. “It’s routine for CDC leadership to review and flag concerns about MMWR papers, especially relating to their methodology, leading up to planned publication,” he told The Washington Post.
Bhattacharya, he said, telegraphed concerns about “the observational method used in the study to calculate vaccine effectiveness, and the scientific team is working to address these concerns.”
“Dr. Bhattacharya wants to make sure that the paper uses the most appropriate methodology for such a study,” Nixon added.
An unnamed HHS official also called the methodology predisposed to bias, noting it focused on hospitalized patients and thus fails to represent the broader U.S. population.
Bhattacharya, who is also director of the National Institutes of Health, is now set to meet with CDC scientists to discuss the report, the official said.
Others pushed back on criticism of the report, including Dan Jernigan, who recently led the CDC’s vaccine safety office. Though he acknowledged the report’s methodology isn’t flawless, Jernigan said it’s still well-suited for tracking vaccine performance.
“It’s a real-world approach where you can’t control differences between people who get vaccinated and those who don’t, and how that influences their likelihood of getting infected,” Jernigan said.
Jernigan, one of several officials who resigned last year amid disputes with Kennedy, then trained his scrutiny toward the HHS secretary, arguing the report’s release might undercut his vaccine narrative.
“The secretary has already taken steps to try and remove the availability of the vaccine from children and others, so if you’re putting out an MMWR that the vaccine is effective at preventing hospitalizations and medical care visits … that message is not line with the direction you’ve been taking with the removal of the vaccine,” he told the outlet.
Kennedy has a long history of dismissing vaccines. He once chaired Children’s Health Defense, a leading anti-vaccine group, and called Covid shots “the deadliest vaccine ever made.”
In September 2025, while speaking to lawmakers about the development of Covid vaccine policy, he claimed: “We were lied to about everything.”
During his tenure at HHS, he’s overseen a number of policy changes when it comes to inoculations. Last year, the former environmental lawyer directed the CDC to drop its COVID vaccine recommendation for children and healthy pregnant women, a move that drew criticism from public health experts. And last month, Kennedy-appointed advisers considered ending recommendations for COVID mRNA vaccines — but ultimately shelved the plan.
The latest incident underscores competing factions inside and outside the administration on vaccine policy, The Washington Post reported. While some officials seek to halt further changes before the midterms, some advocates are pressing Kennedy to double down on his vaccine skepticism.
Public opinion on the COVID vaccines remains divided. According to a September 2025 YouGov survey, 41 percent of Americans believe the benefits of the COVID vaccine outweigh the risks, while 39 percent believe they are about equivalent or outweighed by the risks.
