Donald Trump has signed an executive order with plans for sweeping changes to the childhood vaccination schedule that would require the measles, mumps and rubella (MMR) vaccine to be broken into three separate shots, once it becomes available in the US.
The order recommends that all shots be given at separate medical visits, a frequent point Trump has made despite the safety, ease and lower costs of giving vaccines together.
Bypassing the CDC
The move is an attempt to reinstate changes made earlier this year to the US Centers for Disease Control and Prevention (CDC) vaccination recommendations, which were halted by a federal judge. Health secretary Robert F Kennedy Jr announced in January unilateral changes to the CDC childhood vaccine recommendations. In March, these and other changes to vaccines instituted under Kennedy were halted by a federal judge for violating federal law. By issuing the executive order, Trump is bypassing the CDC, which is the federal agency tasked with recommending vaccines, not the White House.
On a press call, a White House official said the order draws on a Department of Health and Human Services (HHS) scientific assessment published in January 2026, which examined “comparisons of the US to other peer-developed nations” and looked at “where there is consensus amongst our peers on recommendations for immunizations for children”.
Reduced recommendations
The official said the number of recommended childhood immunizations would drop “down to 11 diseases”, compared with 18 at the end of 2024.
Only six of the 17 vaccines currently routinely recommended for all children in the US would continue to have full recommendations: measles, mumps, rubella (MMR), diphtheria, tetanus, pertussis (DTaP), polio, Hib, pneumococcal disease, HPV and varicella.
“Together, there could be a possibility they’re quite lethal,” Trump said of the MMR vaccine at the signing of the order on Monday. Asked if he had evidence that the combined MMR vaccine was “lethal”, Trump said: “No. What I’ve heard is that there are some people who say it is that way.”
Five other shots would be recommended only for those at high risk: monoclonal antibodies to protect against respiratory syncytial virus (RSV) as well as vaccines against hepatitis A, hepatitis B and meningococcal ACWY, which is recommended for teens and high-risk infants. Dengue and meningococcal B vaccines are also on this list, but dengue was already recommended only for those at risk and meningococcal B was shared clinical decision-making.
And six shots would be pushed to shared clinical decision-making: hepatitis A, hepatitis B, rotavirus, meningococcal disease, influenza and Covid-19. This is a previously obscure category that means a provider would be required to weigh the risks and benefits, despite strong evidence for the safety and efficacy of these vaccines.
Logistical strain and legal challenges
On the call, the White House official said vaccines moved into this category “still are a recommendation, and so we assume that that means they’ll still be covered by insurance” and remain “available to parents that want them”, adding: “The president is interested in getting parents more choice and flexibility.”
The executive order would also require the MMR vaccine to be broken into three separate shots, which is not currently possible in the US as there are no separately licensed vaccines for measles, mumps and rubella and the licensing process takes years.
The order also states that, “to the maximum extent feasible, all childhood immunizations should be administered at separate medical visits”. This would put a financial and logistical strain on families and medical providers by creating several additional visits.
The US attorney general would also be tasked with challenging state laws that conflict with the executive order. The US has no vaccination mandates. Shots that are required for school attendance are set at the state and local level.
Both Trump and Kennedy made repeated mentions of autism throughout the order signing, emphasizing a scientifically unproven link between vaccines and the condition. Dozens of studies show no link between the two.
“Today we’re proud to officially announce the United States of America’s gold standard childhood vaccination recommendations. That has to do with many subjects including autism in particular,” Trump said at the beginning of the order signing.
“I’ve seen proof of it, where they have a vaccination where it looks like the size of a bottle of soda, poured into a little child’s body and bad things happen in too many cases,” Trump later said on breaking up each shot into an individual medical visit, before adding: “This is an explosion, it’s an epidemic,” in an apparent reference to autism.
Kennedy claimed at one point: “Something happened in the mid-90s that changed our children, and it has to be an environmental exposure.”
On the call, officials were pressed on why Kennedy has not yet delivered the finding on the cause of autism he had promised by the previous September, and why the US president continued to suggest a vaccine-autism link without new supporting evidence from HHS. An official declined to engage directly, asking to keep the discussion “germane to today’s executive order” rather than address the broader autism-research timeline.
Asked about criticism from the American Academy of Pediatrics that the administration invoked autism repeatedly during the signing without offering any concrete support for families already raising children with autism, an official pointed instead to a toolkit the Centers for Medicare and Medicaid Service released on applied behavior analysis services, framing it as guidance to help states serve autistic patients and curb fraud in relevant programs.
Rebuking these claims and ties to autism, Bill Cassidy, a Louisiana senator, tweeted in response to the order that it “is so wrong”.
“I’m a doctor. This executive order is wrong. The President does not have the expertise to make these changes. Vaccines are overwhelmingly safe. Vaccines are effective. Vaccines DO NOT cause autism. Breaking up vaccines will mean children have to get more shots to get the same protection, not fewer shots. It will increase hesitancy and make children less safe. Parents should listen to their child’s pediatrician about vaccines rather than listening to an inaccurate executive order. This is so wrong,” Cassidy wrote.
Limited legal effect
Executive orders are meant as guidance to federal agencies; they are not laws passed by Congress, and thus they have no legal effect on the public.
The White House official estimated that 28 states “have implemented their own vaccine recommendations or diverged from the federal guidance”. The order is intended to ensure the remaining states “are aware of this information as they go into … their legislative sessions”, they said, and weigh “what vaccine requirements they want to implement as law in their state, particularly … school attendance and entry requirements”.
“This should have no direct operational effects,” says Dorit Reiss, a vaccines expert at UC Law San Francisco. Twenty-nine states and the District of Columbia have decoupled their vaccination requirements from the CDC, and insurance continues to cover the shots. However, “Trump has influence,” Reiss said, and the order may intensify “political pressure on states” to change school requirements.
