Dr. Mehmet Oz publicly pushed back on President Donald Trump’s warning that the combined measles, mumps and rubella vaccine could potentially be “lethal,” telling CBS that the widely used childhood shot is not deadly.
Oz, who leads the Centers for Medicare and Medicaid Services, was pressed repeatedly Sunday during an appearance on CBS’ “Face the Nation” about remarks Trump made earlier this month while signing an executive order addressing childhood vaccination recommendations.
“The MMR vaccine is not a lethal vaccine,” Oz eventually told host Margaret Brennan.
Trump had previously raised concerns about administering the measles, mumps and rubella vaccines together in a single shot and called for the components to be separated.
“Together there could be a possibility they are quite lethal,” Trump said while signing the order. “Separately it looks like they are not at all lethal, but just very effective.”
Brennan asked Oz directly Sunday whether he wanted to clarify the president’s remarks.
Oz initially shifted toward Trump’s broader emphasis on allowing patients and parents to discuss medical questions with their doctors.
“The president wants Americans — he said this many times — to get to the doctors as often as they can,” Oz said.
Brennan continued pressing him, noting that separate measles, mumps and rubella vaccines are not currently offered in the US.
“MMR is not offered in three shots,” Brennan said. “Merck could not offer that. The president called that single shot lethal. Do you want to clarify that?”
Oz then responded directly that the MMR vaccine is not lethal.
The exchange came after Trump signed an executive order earlier this month seeking changes to federal childhood vaccination guidance and encouraging states to reconsider some vaccine requirements.
Oz said the administration is also focused on ensuring that parents have opportunities to raise questions about vaccines and seek exemptions where permitted.
“The request of the president is to make sure that states offer parents either eligibility because of religious beliefs or other reasons why they may not want to have their kids take all the vaccines in order,” Oz said.
The debate comes as measles cases have increased across the US.
According to figures cited in the Daily Mail report, 92.4% of US kindergarten students were vaccinated against measles during the 2025-2026 school year, down from 95.2% in 2019-2020.
Public health officials generally cite vaccination rates of about 95% as necessary to maintain herd immunity against measles because of the virus’ high level of contagiousness.
The MMR vaccine has been used for decades to protect children against measles, mumps and rubella.
Trump’s proposal to separate the three vaccines would face a practical obstacle because individual measles, mumps and rubella vaccines are not currently marketed separately in the US, per the Daily Mail.
Despite Trump’s concerns about the combined shot, his administration has encouraged parents to vaccinate their children against measles as cases have risen.
Oz’s Sunday comments marked one of the clearest responses from a senior Trump administration health official to the president’s warning about the MMR vaccine.
