California Defies Trump's Plan to Split Childhood Vaccines

Trump signed an executive order Monday directing the government to promote splitting the MMR vaccine into three individual shots. Separate doses are not licensed or available in the United States.

• No published evidence shows splitting MMR into three shots is safer or beneficial.
• South Carolina recorded nearly 1,000 measles cases after vaccination rates declined.
• The order also moves some vaccines from universal recommendations to 'shared clinical decision-making.'
• More visits required per child would increase missed work, cost, and dropout from vaccine series.

Why it matters: Requiring more office visits to complete childhood vaccinations strains parents, particularly in rural areas with few pediatricians.

• Downgrading a vaccine from 'routinely recommended' signals to parents it may be less necessary, pediatricians argue.

How 42 sources split on this story

Where they split: The dispute is whether the executive order reflects legitimate parental choice or undermines an evidence-based schedule without scientific justification.

What’s next: The AAP schedule remains in effect; vaccines are still covered at no cost under current law.

• Will manufacturers seek licensure for separate measles, mumps, and rubella vaccines, and on what timeline?
• How many states or school systems will adjust vaccine requirements in response to the executive order?