Nicolai Haugsted
Trump takes another swing at childhood vaccine schedule with controversial proposal.
Donald Trump’s overhaul of America’s childhood vaccination policy may be about to take another significant step.
Less than two months after ordering changes to the number and combination of vaccines recommended for children, the president says his administration now wants pharmaceutical companies to rethink how certain shots themselves are administered.
Trump’s proposal would divide some childhood vaccines into five smaller doses, spread across a period of two years.
His reasoning goes considerably further. Trump says he believes the change would produce a “massive reduction” in autism.
Scientific research does not support that claim. Large studies conducted over decades have found no causal relationship between childhood vaccination and autism, while a new World Health Organization evidence review covering research through 2025 reached the same conclusion.
Trump wants five shots instead of one
Speaking during an Oval Office event on Friday, Trump said his administration would push vaccine manufacturers to divide certain vaccines into doses containing 20 percent of the usual amount.
“We’re going to recommend that they do five doses … and that they be given in six-month intervals so that a small amount of the vaccine gets pumped into the body,” Trump said according to Reuters.
Trump did not identify which vaccines would be affected.
Details about how such a system would be introduced also remain unclear, including whether manufacturers would be required to develop new formulations or seek additional regulatory approval.
Trump initially described the policy as a recommendation before making his intended approach considerably clearer.
“We’re going to be recommending that and actually demanding it,” he said.
President predicts dramatic drop in autism
Trump tied the proposed dosing change directly to autism.
“The vaccine size will be much, much less,” he said. “I think you’re going to see a massive reduction in autism. And that’s a big deal, a very big deal.”
No scientific evidence supporting that prediction was presented by Trump during Friday’s announcement.
WHO’s latest systematic review examined peer-reviewed research published between 2010 and August 2025 and found no evidence supporting a causal relationship between vaccines and autism spectrum disorder.
Research has similarly found no autism link involving the MMR vaccine, thiomersal or aluminium-containing vaccine ingredients.
Vaccine specialists have also questioned Trump’s specific idea of administering fractional doses six months apart. Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, told CNN that such an approach could leave vaccines ineffective rather than make them safer.
Friday’s proposal follows a broader effort by the Trump administration to remake the childhood vaccination schedule.
Trump signed an executive order in August seeking to limit the routine schedule to 11 immunizations, arguing that American children could receive what he called “gold-standard” protection while getting fewer shots.
The same order called for separate measles, mumps and rubella vaccines rather than the combined MMR shot. Individual versions of those vaccines are not currently licensed in the United States, meaning the change cannot simply happen overnight.
WHO has previously examined the question of separating the three vaccines and found no evidence supporting routine use of individual measles, mumps and rubella vaccines instead of MMR. Its vaccine-safety committee has warned that separating them can increase the risk of incomplete immunization.
Kennedy has pushed the issue for years
Health Secretary Robert F. Kennedy Jr. has long questioned established vaccine policy and promoted claims linking vaccines to autism.
Scientists and major medical organizations have repeatedly rejected such a causal link.
WHO revisited the issue again in its latest evidence review, examining studies involving vaccines generally as well as research specifically involving thiomersal. Its conclusion remained unchanged.
Kennedy’s influence has nevertheless helped move vaccine policy much closer to the center of Trump’s second-term health agenda.
Recent changes have already generated political friction. Trump’s current nominee for surgeon general, Dr. Nicole Saphier, told senators during her confirmation hearing this month that vaccines do not cause autism and defended the MMR vaccine while facing questions about the administration’s direction.
Plenty of questions remain before five becomes the new one
Trump’s announcement leaves vaccine manufacturers, doctors and parents without several important details.
No list of affected vaccines has been released, no implementation date was announced, and Trump did not explain what legal mechanism his administration would use to force pharmaceutical companies to adopt the five-dose model.
