Delay in CDC Report Raises Concerns Over Vaccine Integrity

A Trump administration appointee has postponed the release of a Centers for Disease Control and Prevention (CDC) report highlighting the benefits of the Covid vaccine, raising alarms about the administration’s tactics that may undermine vaccination efforts.

According to research from CDC scientists, the Covid vaccine reportedly reduced the chances of emergency room visits and hospitalizations among healthy adults by approximately 50% last winter, as per reporting from the Washington Post. The acting CDC director, Jay Bhattacharya, allegedly withheld the report’s publication over concerns regarding the research methodology.

This decision to delay the CDC report has sparked worries among experts and former officials about ongoing efforts by the Trump administration to challenge the agency’s vaccine-related activities.

Since taking office in January, Health Secretary Robert F. Kennedy Jr. and his appointees have been involved in various initiatives—both public and covert—that seem aimed at hindering vaccine research and recommendations.

Dr. Fiona Havers, a former senior vaccine policy adviser at the CDC, commented, “This is certainly an escalation of this administration’s attempt to undermine CDC science. The blocking of this report is extremely worrying.” Havers had resigned from the CDC the previous year due to the administration’s approach to vaccine policy.

The CDC’s findings suggested that between September and December 2025, healthy adults vaccinated against Covid experienced a 55% decrease in hospitalizations related to the virus. Those vaccinated were also found to have a 50% reduced chance of needing emergency or urgent care visits.

This report was initially scheduled for release on March 19 in the CDC’s scientific journal but is now being delayed as Bhattacharya reviews the methodology and plans to meet with CDC scientists for further discussions.

The methodology in question, known as “test-negative design,” has been a commonly used approach for about two decades, according to both Havers and the Post’s reporting. This design evaluates vaccination rates among sick patients. Given the CDC’s stance on promoting the Covid vaccine, conducting a placebo test would be considered unethical, Havers explained.

Interestingly, just a week before the intended publication of the Covid report, a different study on flu vaccine effectiveness was released in the CDC’s Morbidity and Mortality Weekly Report, utilizing the same methodology as the Covid research, according to the Post.

“There was nothing new or unexpected in the report or its methods,” Havers noted. “The fact that a political appointee halted it is quite concerning.”

Kennedy has been a prominent critic of Covid vaccines, and the administration appears to be trying to alter public perception of these vaccines as the 2026 midterms approach. This recent controversy over the Covid-19 vaccine report indicates that the administration may be resorting to underhanded tactics to advance its agenda.

Kennedy previously referred to the Covid-19 vaccines as the “deadliest vaccine ever made” and had also called on the CDC to stop recommending the vaccine for healthy pregnant women and children.

During the peak of the Covid-19 pandemic in 2020, Bhattacharya was against lockdowns and mask mandates. He was nominated by Trump in 2024 to head the National Institutes of Health (NIH) and took over as CDC director in February.

A CDC spokesperson stated, “It’s common for CDC leadership to review and express concerns about MMWR papers, especially regarding methodology.” The spokesperson acknowledged that Bhattacharya is worried about the observational method used to assess vaccine effectiveness and that the scientific team is addressing these concerns.

Kennedy’s leadership at the Department of Health and Human Services has led to considerable upheaval within the agency and its affiliates. Last year, he dismissed all 17 members of a vaccine advisory committee, replacing many with individuals who also seem to oppose vaccines.

Numerous CDC employees, including Havers, have resigned in protest against Kennedy’s actions.

“The report indicated something this administration doesn’t want publicized—that Covid vaccines are effective in preventing severe illness,” said Havers, who resigned from the CDC last June. “It’s a dangerous step they’ve taken, albeit behind the scenes.”