On March 16, 2026, U.S. District Court Judge Brian E. Murphy granted an injunction preventing HHS from revising the childhood immunization schedule and staying the appointments of thirteen members of the CDC Advisory Committee on Immunization Practices (ACIP). A legal challenge to these changes to the vaccine schedule seemed all but inevitable when they were made, as Robert F. Kennedy Jr.’s actions as health secretary over the past year have grown more and more polarizing. Vaccine supporters began to sound the alarm in June 2025 after Secretary Kennedy suddenly fired all seventeen members of ACIP, citing a need for a “clean sweep” to “re-establish public confidence in vaccine science.” However, Secretary Kennedy’s actions as head of HHS have continued to amplify the Trump administration’s skepticism of vaccines rather than solidify confidence in them. In a press conference in September 2025, President Trump made comments on vaccines and the childhood vaccine schedule, claiming that groups of people who do not use vaccines do not have autism and that they are injecting “a vat of eighty different vaccines” into young children. Trump also noted his distrust in the presence of aluminum and mercury in vaccines and his desire for vaccines for mumps, measles, and rubella to be taken separately rather than all together in the MMR vaccine. Trump provided limited scientific support for these views at that time, stating “this is based on what I feel,” yet a few months later in December 2025, he released a Presidential Memorandum directing Secretary Kennedy to review vaccine schedules from other peer countries which vaccinate for fewer diseases and revise the childhood vaccine schedule to conform to best practices. This memorandum prompted HHS to release a decision memo updating the childhood vaccine schedule on January 5, 2026.
Although Secretary Kennedy and President Trump’s stated policy goal of these actions was to improve confidence in vaccines, in practice these actions actually may lead to less confidence in vaccines and the government entities that govern public health. Physicians are noticing that they are getting more questions from families regarding the childhood vaccine schedule due to the changes. Physicians report that changes have caused confusion and anxiety for parents regarding which vaccines are appropriate and when they should be administered, and this confusion is leading some physicians to disregard the changes altogether and follow recommendations made by the American Academy of Pediatrics. The American Academy of Pediatrics was one of many groups who sued HHS to block the changes to the vaccine schedule and stay the appointment of other vaccine skeptics to the ACIP, arguing that these actions violated the Administrative Procedure Act because they constituted arbitrary or capricious agency action not in accordance with statutory authority. Although Judge Murphy granted the injunction staying the appointments due to their likelihood of success on the merits, likelihood of suffering irreparable harm in the absence of preliminary relief, balance of equities in their favor, and the fact that injunction would be in the public interest, this decision is not necessarily permanent. Whether or not the changes to the vaccine schedule and the appointments to ACIP are allowed to stand will come down to the result of a trial or a decision for summary judgment. No matter the final outcome of the litigation, the changes and associated legal challenges alone may worsen public confidence in vaccines more than these policies could ever improve it. The resulting instability in policy highlights the importance of following the appropriate protocols for agency rulemaking.