A federal judge in Massachusetts on Monday blocked Health Secretary Robert F. Kennedy Jr.’s recent overhaul of the nation’s childhood vaccine schedule — a major blow to his vaccine agenda.
The ruling stems from a lawsuit the American Academy of Pediatrics (AAP) and other medical groups brought against the Department of Health and Human Services, arguing that Kennedy’s changes to vaccine recommendations and to an influential vaccine advisory committee violated federal law.
In January, Kennedy and the Centers for Disease Control and Prevention made sweeping changes to the childhood vaccine schedule, reducing the number of recommended diseases to be vaccinated against from 18 to 11. The change dropped recommendations that all babies should be protected against hepatitis A, hepatitis B, RSV, dengue and two types of bacterial meningitis.
In response, more than 200 groups, including the American Medical Association, the March of Dimes and the Autism Science Foundation, announced they would disregard the changes and follow the AAP’s immunization schedule, instead.
The judge also put on hold the new members Kennedy has appointed to the CDC’s vaccine advisory committee since June. The Advisory Committee on Immunization Practices helps shape U.S. vaccine policy, including recommendations that influence the childhood vaccine schedule and which shots insurance must cover.
The panel was scheduled to meet Wednesday and Thursday. According to the AAP’s attorney, Richard Hughes, the judge’s decision essentially stops the meeting from happening.
An HHS official confirmed that the meeting had been postponed.
The ruling also stayed any of the votes Kennedy’s ACIP has taken since June, including a vote to no longer recommend the hepatitis B vaccine for all newborns.
The decision is a setback for Kennedy, a longtime anti-vaccine activist who promised to restore trust in the public health agencies, but whose controversial policies have created confusion among pediatricians and contributed to more distrust of childhood vaccination, experts say. A recent survey from the Annenberg Public Policy Center of the University of Pennsylvania found that trust in public health agencies has fallen in President Donald Trump’s second term.
“Today is a day to celebrate the triumph of science over misinformation,” said Dr. Richard Besser, president of the Robert Wood Johnson Foundation. “This is a huge blow to Kennedy’s vaccine policies.”
Dr. Andrew Racine, the AAP’s president, said the ruling “re-established a degree of clarity” about childhood vaccinations. “If anyone has any questions about what’s the appropriate vaccine schedule for their children, the best thing to do is to talk to their pediatricians.”
An HHS official said the agency will appeal the decision. Hughes suggested the case could make its way to the Supreme Court.
In a statement, Andrew Nixon, a spokesperson for HHS, said the agency “looks forward to this judge’s decision being overturned just like his other attempts to keep the Trump administration from governing.”
Kennedy has made a series of moves to reshape federal vaccine policy since he took office.
In June, Kennedy fired all 17 members of ACIP and replaced them with his own appointees, many of whom are critical of vaccines.
He also issued new rules for how vaccines are tested, a move experts said would make it harder to approve new shots. Kennedy has also moved to limit the use of Covid vaccines — making them harder to get for people under 65 — and removed a recommendation that healthy kids and pregnant women get the shots. He has also taken a harder line on shots that use mRNA technology.
CORRECTION (March 16, 2026, 6:08 p.m. ET): A previous version of this article misstated how the vaccine recommendations changed under Kennedy. The CDC changed the number of recommended diseases to be vaccinated against from 18 to 11, not the number of shots.
