US President Donald Trump signed an executive order Monday directing changes to the nation’s childhood vaccination schedule, limiting recommended immunizations to 11 core vaccines along with the measles, mumps and rubella (MMR) vaccine.
Trump said the changes would provide American children with “gold-standard” protection while bringing the United States closer to countries that recommend fewer routine childhood vaccinations.
The executive order advances a long-standing objective of Health Secretary Robert F. Kennedy Jr., a prominent vaccine critic who has repeatedly promoted claims linking vaccines to autism, despite extensive scientific research finding no evidence of such a connection.
During a White House signing ceremony, Trump repeatedly referred to the rising number of autism diagnoses in the United States and questioned whether vaccines could play a role.
The order also calls for the MMR vaccine to be administered as three separate shots during different medical visits.
Doctors Reject Changes to Vaccine Schedule
Medical organizations and public health experts strongly criticized the move, arguing that there is no new scientific evidence supporting a reduction in the recommended childhood vaccination schedule.
Experts said the US immunization program reflects decades of research and is designed around the specific health risks faced by American children.
Dr. Aaron Milstone of the American Academy of Pediatrics said the biggest immediate consequence could be confusion among parents, potentially causing some families to delay vaccinations.
Merck also said there is no published scientific evidence demonstrating a benefit from separating the MMR vaccine into three individual shots. The company warned that using separate components could increase the number of injections and potentially lead to delayed or missed vaccinations.
Dr. Elizabeth Mack, a pediatric critical care physician in South Carolina, noted that individual licensed measles, mumps and rubella vaccines are not currently available in the United States, raising practical questions about how the administration’s recommendation could be implemented.
Kennedy’s Vaccine Overhaul Faces Legal Challenges
The executive order seeks to reinforce changes previously pursued by Kennedy, who moved in January to remove vaccines targeting six of 17 diseases from the federal immunization schedule.
A federal court subsequently blocked that move, and the issue remains under litigation.
The latest order also directs the Justice Department to challenge state vaccination laws that the administration argues conflict with parental rights, religious freedom, disability protections and equal-protection requirements.
The Vaccines for Children program, which provides government-funded vaccines to eligible families who may otherwise struggle to afford them, is expected to continue under the new policy, according to a senior administration official.
Experts Challenge Trump Administration’s Claims
Trump and Kennedy have argued that the previous vaccination schedule required children to receive as many as 72 injections.
Vaccine experts disputed that figure, noting that it counts combination vaccines such as MMR as multiple separate shots and includes recurring annual vaccinations for influenza and COVID-19.
Experts also stressed that countries with different vaccination schedules face different disease risks and operate under different healthcare systems.
The administration’s renewed focus on investigating a possible connection between vaccines and autism has also drawn criticism.
American Academy of Pediatrics President Dr. Andrew Racine said decades of research have already found no link between vaccines and autism.
“The science is done,” said Dr. Alycia Halladay, chief science officer of the Autism Science Foundation, arguing that the evidence has repeatedly failed to support the claimed connection.
Republican Senator Also Criticizes Trump Order
The executive order also faced criticism from Republican Senator Bill Cassidy of Louisiana, a physician who chairs the Senate Health Committee and previously supported the confirmation of Kennedy.
“I’m a doctor. This executive order is wrong. The president does not have the expertise to make these changes,” Cassidy said in a statement.
The dispute is expected to fuel an intensifying political and legal battle over childhood vaccination requirements, as the Trump administration pushes to reshape federal health policy while medical organizations warn that fewer recommended vaccinations could leave children more vulnerable to preventable diseases.
