HHS rejects publication of study showing Covid-19 vaccines prevent hospitalizations, ER visits

By Brenda Goodman, CNN

(CNN) — Covid-19 vaccines roughly halved the chances that a US adult would need to visit the emergency room or be hospitalized with their infections last fall and winter, according to two sources familiar with the findings of a new study. But you won’t hear about it from the agency that led the research: the US Centers for Disease Control and Prevention.

The current head of the CDC, Dr. Jay Bhattacharya, who’s also director of the US National Institutes of Health, blocked the publication of those findings in the CDC’s flagship journal, the Morbidity and Mortality Weekly Report, according to the sources.

The authors of the study received an official rejection letter from the journal on Tuesday, one source said, even though the study had cleared internal reviews and had been scheduled for publication.

Andrew Nixon, deputy assistant secretary for media relations at the US Department of Health and Human Services, confirmed that the study had been rejected.

“Scientific reports are routinely reviewed at multiple levels to ensure they meet the highest standards before publication. The MMWR’s editorial assessment identified concerns regarding the methodological approach to estimating vaccine effectiveness and the manuscript was not accepted for publication,” Nixon told CNN.

The rejection is unusual because the study followed the normal methods the agency uses to estimate the effectiveness of vaccines against seasonal respiratory viruses, and it utilized the CDC-led VISION collaboration, which stands for the Virtual SARS-CoV-2, Influenza and Other Respiratory Viruses Network. The network uses electronic health records from nine US health systems to monitor vaccine effectiveness from season to season in various age groups.

According to sources familiar with the episode, Bhattacharya took issue with the study’s so-called test-negative design. HHS did not answer a question about what, exactly, Bhattacharya’s concerns had been.

Test-negative studies look at all the people who go to the doctor for a specific symptom or set of symptoms. They then compare vaccination status of people who test positive for a given infection against that of people who test negative for that same infection to derive an estimate of the effectiveness of the vaccine. Test-negative designs help minimize a type of bias called the healthy user effect, with which people seeking medical care may look sicker because they’re more likely to be diagnosed with a disease or condition, compared to people who don’t seek care for their symptoms.

It’s become the standard way of measuring vaccine effectiveness, not only for Covid but for other seasonal respiratory viruses like influenza and respiratory syncytial virus, or RSV.

The rejection of the new study is “pretty problematic in general, because it’s a very standard, well-established study design that has been used for a long time,” said Dr. Fiona Havers, who resigned as senior vaccine policy adviser at the CDC in June over changes to the agency’s vaccine policy made by HHS Secretary Robert F. Kennedy Jr. She used to be part of the team that worked on studies with VISION data.

“It’s not perfect, but it is a reasonable way of measuring real-time vaccine effectiveness during the season and getting data that can be tracked over time,” she said.

“This network has published in New England Journal of Medicine and The Lancet and all of these other very high-profile journals in the past,” Havers added. “This seems like pretty aggressive interference by a political appointee into CDC scientific processes.”

The rejection of the study was first reported by the Washington Post.

Two weeks ago, after the first round of news stories that detailed a delay in the study’s publication, Bhattacharya met with the study authors, who refused to adjust the methodology.

“His request for a change in methodology is really too late after the fact,” said Dr. Deb Houry, who was the CDC’s chief medical officer until she resigned in August in solidarity with Dr. Susan Monarez, who was ousted by Kennedy just weeks into her tenure as CDC director over her refusal to rubber-stamp vaccine recommendations by his hand-picked agency advisers.

“In general, their methodology was appropriate and has been used in other studies,” Houry said. “I reviewed MMWR as in my role as acting principal deputy and chief medical officer for approximately four years, and I very rarely rejected a paper late this in the process.”

Covid-19 vaccines have been a particular target of the HHS under Kennedy.

In June, he announced that Covid-19 vaccines would no longer be recommended for pregnant women and children, a move that blindsided and alarmed many agency scientists.

In September, the agency’s new vaccine advisers removed the CDC’s blanket recommendation for Covid-19 vaccines for everyone 6 months and older, and instead recommending that the vaccines be given after shared clinical decision-making, meaning with a recommendation or prescription from a doctor or pharmacist.

A March meeting of the vaccine advisers was due to report on injuries related to Covid-19 vaccines, but the meeting was postponed after a legal ruling that temporarily stopped some of the administration’s vaccine-related policy changes and activities.

In congressional hearings Tuesday, Kennedy once again denied that his vaccine views played a role in declining vaccination rates and disputed that he has been anti-vaccine.

“The problem is not me. There are people in this country who do not vaccinate,” Kennedy said during a House hearing.

CNN’s Sarah Owermohle contributed to this report.

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