U.S. President Donald Trump signed an executive order on Monday calling for fewer childhood vaccinations by limiting the inoculation schedule to 11 immunizations.

The order also recommended splitting the childhood measles, mumps and rubella vaccine into three shots and delivering the shots at separate medical visits

Public health experts say the immunization schedule was based on decades of evidence showing the vaccines could protect against serious illness and death, and that the number of shots reflect the specific health needs of Americans. They say reducing the recommended vaccines will leave more children vulnerable to preventable diseases.

“Effective immediately, my administration is recognizing gold standard childhood vaccine recommendations for only 11 core vaccinations against the most serious and dangerous diseases, along with the MMR, which hopefully will be split up,” Trump said during a White House signing ceremony.

“America has recommended more childhood vaccines than any peer nation, and even twice as many doses as some European countries,” he said.

U.S. Health Secretary Robert F. Kennedy Jr., a longtime vaccine critic, has previously led efforts to drop universal recommendations for hepatitis B shots for children and reducing the list of recommended vaccines, citing links to autism that scientists have repeatedly debunked.

—

(Reporting by Jacob Bogage and Ahmed Aboulenein; Additional reporting by Ismail Shakil and Ryan Patrick Jones; Editing by David Ljunggren)