WASHINGTON — A possible Trump administration effort to change the childhood vaccine schedule left hospital leaders, health policymakers, and pediatricians scrambling to navigate what could be the most significant changes to the American vaccine program in decades.
The administration had planned to announce on Friday moves to pare down the number of shots on the U.S. schedule to make it more like Denmark’s, according to an official familiar with the plans who was not authorized to speak publicly. That announcement was delayed, officially due to scheduling reasons. But there were also concerns that moving ahead could be legally or politically risky, the official said.
Still, changes to the schedule are expected in the new year, the person said, though they cautioned that the situation remains fluid. Under a Denmark-style vaccine schedule, the U.S. might no longer recommend shots for diseases like chickenpox, hepatitis A, rotavirus, and influenza, according to an analysis from The Evidence Collective. The U.S. schedule currently recommends vaccination against 16 diseases.
It’s not clear to public health experts why the U.S., with a population 57 times larger and a vastly different health care system, would model its vaccine policies on Denmark. The nation has one of the most limited lists of recommended shots among peer countries.
Should the administration follow through, it would mark a significant departure from how the U.S. has handled such changes for decades, including only dropping shots when new data pointed to serious adverse events. The end result of the changes, public health experts worry, would be fewer vaccinations and more disease.
The Health and Human Services Department did not respond to requests for comment.
As they await more information, many parts of the health system have been strategizing about how they may respond.
Health providers, after seeing the first reporting about the changes from CNN, called their policy consultants and lobbyists to determine how to respond.
“They’re freaking out right now,” one of the lobbyists on the calls, who represents several health systems, told STAT.
Hospital leaders on the calls expressed fear that a change in the schedule could lead to less insurance coverage for shots that are no longer recommended and more liability risk for providers, undermining systems specifically set up to protect access to recommended shots.
Hospitals have taken a constrained approach so far, waiting for an official statement from the administration before publicly responding.
The lobbyist said that even once any change is publicly announced, health system leaders worry that their responses could put them in the crosshairs of an administration that has been quick to cut research funding and government reimbursement, a fear that has been constant for providers through Trump’s second term. Systems in Republican-led states are also concerned about repercussions from state officials, the lobbyist said.
The plans emerged after the White House ordered health officials to compare the U.S. vaccine schedule to those in other countries “while preserving access to vaccines currently available to Americans,” according to a Dec. 5 memo from Trump.
Previously, members of the vaccine advisory committee for the Centers for Disease Control and Prevention said they planned to look into changes to the schedule. The changes are part of a larger shift in vaccine policy under the Trump administration, led by once-anti-vaccine activist and current HHS Secretary Robert F. Kennedy Jr.
Reporting on the plans comes amid a dizzying series of other major health policy changes, related to drug pricing, Medicare payments, and gender-affirming care. The flurry of action has made it even more difficult for health system executives and their advisers to make sense of their Washington strategies for the coming months.
Major changes to the childhood vaccine schedule, maintained by the CDC, could result in a deeper balkanization of state public health policies. States often use the CDC list to establish school entry requirements, according to Jason Schwartz, associate professor of health policy at the Yale School of Public Health.
But some have begun turning to other sources as well, and the impacts will depend on the details of any federal action.
“I know that states have been looking at their laws and regulations for months anticipating these sorts of implications,” he told STAT. “However, a big detail that’s not been clarified publicly yet is whether the ‘shared-decision making’ statement will remain for any vaccines that come off the routine schedule.”
A shared decision making recommendation means that people should talk with their health care provider about whether a particular vaccine is needed. Generally, vaccines with this status are still covered by health insurance.
Critics of existing policies — including multiple members of Kennedy’s handpicked vaccine advisory panel — argue it gives parents more agency in the vaccines their children get. But for years doctors have complained about the practice, saying that having to have these discussions takes up too much time and conveys a message that a vaccine isn’t wholeheartedly endorsed by the CDC.
David Mansdoerfer, a former senior HHS official during the first Trump administration, suggested the changes would be welcome to some states that would like to adjust their policies.
“I would argue there’s actually a lot of positives to that because each state has different public health issues,” he said. “[States will] have a little bit greater leeway than [they] did under the traditional model where everyone just points to CDC as the end-all be-all.”
Another former senior Trump administration official, who asked not to be identified, said the federal government, using the scientific power of the CDC and Food and Drug Administration, has a responsibility to provide federal recommendations, rather than forcing states to issue their own.
The first Trump administration, the person said, was pro-vaccine, so long as they didn’t include mandates. Now, the reported potential changes coming from HHS seemingly lack a scientific backing, they said, and should the department move forward, hundreds, if not thousands, of children could die from preventable illnesses.
Demetre Daskalakis, a former senior CDC official who oversaw the immunizations and respiratory diseases programs, said that moving to a Denmark-inspired schedule could cause problems on a lot of levels, depending on the details, such as whether the recommended timing of vaccinations is affected.
Existing school vaccine mandates could be thrown “into chaos,” he said.
“Because if every vaccine becomes shared clinical decision making, then I think it becomes very state by state — what is on their list and what’s not,” he said. States might be unsure about their legal footing to require shots.
“If we’re the ones dictating which vaccines are required for schools — which is well within our purview — but then we don’t have the backing of the federal government, does that open us up to all sorts of litigation?” he said.
Whether or not HHS has the legal authority to unilaterally change the schedule is a gray area, some experts suggested.
“Precedent for this approach was set in May 2025 with changes to the pediatric and pregnancy Covid-19 vaccine schedule. That directive resulted in an immediate update to the CDC vaccine schedule,” a fact sheet by The Evidence Collective, a group of public health experts, published Friday reads.
However, those changes are being fought over in court. In July, major medical groups sued HHS, saying the changes were unlawful and diminished public trust. A judge is expected to weigh in on whether to grant the government’s motion to dismiss in early January.
Sara Rosenbaum, a professor emerita at the Milken Institute School of Public Health at Georgetown University, said that Kennedy does not have the legal authority to unilaterally change vaccine schedules.
“He cannot. I have no idea what authority he planned to cite for such an action,” she said in an email.
Rosenbaum noted that the normal process — with the Advisory Committee on Immunization Practices making recommendations that are then accepted or rejected by the CDC director or the health secretary — involves advance notice of planned votes in the Federal Register, an opportunity for the public to comment, and public discussion of the relevant scientific evidence.
Mansdoerfer told STAT that the U.S. no longer recommending certain vaccines alone might not be enough to invite a strong legal argument unless the administration takes steps to limit coverage of the shots.
“[Manufacturers] could probably talk about arbitrary and capricious, like the way [HHS] made this decision was wrong, and if that led to vaccines not being covered in certain instances or circumstances, that’s probably where you’d have the most interest, would be my guess,” he said. “But states and local governments really have the true legal authority on most public health, so I don’t see it from a recommendation side having that much risk.”
Rather, he expects it might make seeking religious exemptions to school vaccine requirements easier. HHS has already indicated it will take aggressive action to protect religious exemptions.
The short list of vaccines recommended in Denmark makes the country an outlier among peer nations. Germany recommends vaccination against 15 diseases, while Japan’s schedule includes 14 diseases (it may be in the process of adding one more). Denmark’s schedule has 10.
Some differences between nations’ schedules tend to come from diseases that are prevalent in certain places but not in others. Other differences may stem from how countries consider whether shots are worth their cost.
For example, Japan recommends vaccinating children against tuberculosis and Japanese encephalitis, while the U.S. and European countries generally do not. The U.S. and Germany recommend immunization against influenza and RSV, while Denmark and the United Kingdom don’t.
Isabella Cueto contributed reporting.
