President Donald Trump signed an executive order on Monday directing that the combined measles, mumps, and rubella (MMR) vaccine be administered as three separate, single-disease shots once those products become available domestically. The order seeks to reduce the number of childhood vaccinations, a move the president stated would provide "gold-standard" protection. During a press conference, President Trump also suggested a link between vaccines and autism, despite a lack of scientific evidence for such a connection.
Implementation of the order faces significant delays because single-disease vaccines for measles, mumps, or rubella are not currently licensed or available in the United States. Merck & Co and GSK are the only two manufacturers licensed to produce the combined MMR vaccine for the U.S. market. Merck discontinued production of the individual components in 2008, and these separate shots are not routinely used in most other countries.
Vaccine manufacturers and regulatory experts stated that bringing separate shots to market could take up to a decade. Merck noted that even with expedited review pathways, meeting Food and Drug Administration (FDA) safety and efficacy requirements, followed by manufacturing and commercialization, would be a multi-year process. Jesse Goodman, a former FDA Chief Scientist, said companies would need to triple their filling and vial requirements and might need to build new facilities to create the necessary production capacity.
The scale of the impact involves the entire U.S. pediatric population, as the MMR vaccine is a standard requirement for school entry across all 50 states. While the White House stated it would work with the private sector on market-based solutions for parents seeking "additional options," the cost of this transition would be borne by manufacturers who would need to invest in new testing and facilities. Experts like Dr. Andrew Racine of the American Academy of Pediatrics noted there is currently no indication that manufacturers have an interest in pursuing these separate licenses, which could cost millions of dollars in research and regulatory fees.
Knock-on effects include a potential increase in vaccine hesitancy, which some public health experts warned could expose more children to preventable illnesses. The Centers for Disease Control and Prevention (CDC) and medical groups currently favor the combined shot because it reduces the risk of children missing protection against one of the three diseases. What happens next depends on whether private companies choose to apply for FDA licensing for single-disease shots. Dorit Reiss, a law professor at UC Law San Francisco, suggested companies might wait to see if the policy changes under a future administration before committing to the 10-to-18-month minimum licensing period. Currently, no specific deadline or effective date for the availability of separate shots has been established.