President Donald Trump signed an executive order on Monday aimed at reducing the number of vaccinations administered to American children, reviving debate over vaccine safety and immunization schedules. The order directs health officials to consider separating the combined measles, mumps, and rubella (MMR) vaccine into individual shots, among other changes. At an event held in the Oval Office to announce the measure, Trump and supporters made claims linking vaccines to autism and suggesting potential lethality of the MMR combination vaccine, assertions that health experts say lack scientific support.
Trump’s proposal to split the MMR vaccine into three separate injections runs contrary to decades of evidence affirming the safety and efficacy of the combined shot. The Centers for Disease Control and Prevention (CDC) acknowledges a small risk of febrile seizures following the vaccine but states these seizures do not cause lasting harm. The combined vaccine is widely used for its convenience and cost-effectiveness, and individual vaccines for measles, mumps, and rubella are not routinely available in the United States. Critics, including Dr. Richard Besser, president of the Robert Wood Johnson Foundation and former acting CDC director, argue that fragmenting the vaccine would burden families with more medical appointments and could reduce vaccination rates, increasing vulnerability to preventable diseases.
The executive order also calls for alternatives to aluminum salts, components used in some vaccines to boost immune responses, which have been used safely for nearly a century. Claims by some administration figures that aluminum in vaccines is unsafe are contradicted by extensive research supporting their safety and effectiveness. A small 2022 study suggested a possible link between aluminum adjuvants and asthma but was limited in design and contradicted by larger studies, including one from Denmark that found no association with asthma or other conditions.
Trump asserted that scaling back vaccination would cause no harm, a claim that contrasts with public health data showing the critical role of vaccines in preventing disease and death. According to a recent CDC study, routine childhood immunizations have averted more than 500 million cases of illness and over one million deaths among children born between 1994 and 2023. Health officials warn that declines in vaccination rates are contributing to the resurgence of diseases such as measles, which has seen more cases so far this year than any year since its declared elimination in the U.S. in 2000.
The executive order singles out several vaccines, including those against hepatitis A, hepatitis B, and meningococcal disease, recommending that certain shots be limited to high-risk children. These proposals have raised concern among pediatricians and public health experts who emphasize that many of these vaccines protect against illnesses that can be severe or fatal across the population.
Concerns about the number and volume of vaccines children receive were also raised. Trump characterized the cumulatively administered vaccines as excessive, though experts note that children receive far fewer than the claims of 72 shots, with the total closer to 35 doses, including recommended but not required vaccines like the annual flu shot. Vaccine schedules are the product of extensive review and monitoring by panels of experts and federal agencies. Studies have repeatedly shown that vaccines, both individually and combined, do not overload the immune system.
The administration’s claims linking vaccines to autism remain unsubstantiated. While autism diagnoses have increased over time, experts attribute this to broader diagnostic criteria, increased awareness, and demographic changes, rather than vaccination. Numerous studies have found no causal connection between vaccines and autism spectrum disorders. Federal scientists continue to investigate potential causes of autism, but no new evidence has emerged linking immunization to the condition.
A federal court recently blocked the administration’s appointed vaccine advisory committee from convening, citing concerns about the qualifications of its members, adding to ongoing tension surrounding vaccine policymaking.
Overall, public health officials caution that altering vaccination schedules without scientific basis risks reversing decades of progress in controlling preventable diseases.