New Issue: Orbital Catastrophe Ahead? Read Now

Trump issues executive order aimed at rewriting childhood vaccine schedule

The president called for the combined measles, mumps and rubella (MMR) vaccine to be split into separate shots, despite decades of research showing that the MMR vaccine is safe and effective

Donald Trump holds up an executive order with Robert F. Kennedy, Jr., and Jayme Leagh Franklin on either side.

President Donald Trump signs an executive order calling for more research and flexibility on vaccines, alongside U.S. Secretary of Health and Human Services Robert F. Kennedy, Jr. (right) and Jayme Leagh Franklin (left), founder of the lifestyle website the Conservateur, in the Oval Office of the White House in Washington, D.C., on August 10, 2026.

JIM WATSON/Getty Images

Join Our Community of Science Lovers!

Updated August 10, 2026 at 6:15 PM

President Donald Trump issued an executive order on Monday aimed at altering the U.S. childhood vaccine schedule. The order would nix the current combined measles, mumps and rubella (MMR) vaccine in favor of giving a shot for each disease individually.

The order, a draft of which was obtained by the Washington Post, directs Secretary of Health and Human Services Robert F. Kennedy, Jr., to “present plans” to the president to break up the MMR vaccine into its separate constituents. On Monday Trump falsely suggested that, for the combined vaccines, “there could be a possibility they’re quite lethal, and separately, it looks like they are not at all lethal but just very effective.” Overwhelming evidence shows that the MMR vaccine is both safe and effective, with a low risk of adverse events.

The order directs federal agencies to classify childhood vaccines into three categories: vaccines recommended for all children; vaccines “recommended for certain high-risk groups or populations”; and immunizations given “based on shared clinical decision-making.” It’s unclear whether the order will have any real effect on the nation's vaccine schedule, which is set by the U.S. Centers of Disease Control and Prevention.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Vaccines in the executive order’s first group—those recommended for all children—include vaccines for measles, mumps, rubella, diphtheria, tetanus and pertussis, as well as human papillomavirus (HPV) and polio, among other conditions.

Vaccines in the second group—those for at-risk populations—include vaccines for respiratory syncytial virus (RSV) and hepatitis A and B, and more, according to the executive order. Among those in the third category—vaccines recommended based on decision-making in consultation with a doctor—include vaccines for hepatitis A and B, COVID, influenza, and others.

“To the maximum extent feasible,” the order states, “all childhood immunizations should be administered at separate medical visits.”

The president also suggested, without evidence, that childhood vaccinations could be a cause of rising autism rates. “We do not know exactly what the cause is with respect to autism,” Trump said. “It is essential to our research efforts that we have the very best vaccine recommendations in the entire world, so we're reducing them.” The overwhelming majority of medical experts agree—and the scientific evidence shows—that the causes of autism are multifaceted and may include genetic as well as environmental factors and that rising rates may be attributable to better diagnostics.

In a statement, Michael Osterholm, director of the Vaccine Integrity Project and an epidemiologist at the University of Minnesota, urged parents to trust the science. “Parents should continue to rely on the evidence-based immunization recommendations developed by trusted medical and public health experts, including the American Academy of Pediatrics [AAP]," he said. “Today’s Executive Order does not change the underlying scientific evidence supporting childhood immunization.”

“We encourage parents to discuss questions about vaccination with their pediatrician or other trusted healthcare provider,” Osterholm said.

David Mandell, a professor of psychiatry at the University of Pennsylvania, notes that separating vaccinations into multiple visits will place a “tremendous burden” on already strained primary care pediatricians and will make the process of getting vaccinated “much more challenging” for families. “My fervent hope is that pediatricians and families choose to follow [the AAP’s] vaccination schedule rather than the decidedly unscientific and dangerous one that this executive order puts forward,” Mandell says.

The order is the Trump administration’s latest attempt to overhaul and curtail the childhood vaccine schedule. In January the CDC moved to reduce the number of recommended vaccines for children to those that protect against 11 diseases; previously, the CDC had recommended children receive inoculations for 17 diseases. That action was blocked by a federal judge in March.

Editor’s Note (8/10/26): This is a breaking news story and will be updated.

Jackie Flynn Mogensen is a breaking news reporter at Scientific American. Before joining SciAm, she was a science reporter at Mother Jones, where she received a National Academies Eric and Wendy Schmidt Award for Excellence in Science Communications in 2024. Mogensen holds a master’s degree in environmental communication and a bachelor’s degree in earth sciences from Stanford University. She is based in New York City.

More by Jackie Flynn Mogensen

Subscribe to Support Independent Journalism

Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.

When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.

Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber

Thank you,

Jeanna Bryner, Editor in Chief, Scientific American

Subscribe