Dr. Mehmet Oz pushed back directly against Donald Trump’s assertion that the MMR vaccine could be “lethal,” after facing repeated questions about the president’s comments.
Oz, who leads the Centers for Medicare and Medicaid Services, was pressed during a tense Sunday interview on CBS’ Face the Nation after Trump suggested, without evidence, that administering the measles, mumps and rubella vaccines together in the standard combined shot could potentially be deadly.
Host Margaret Brennan repeatedly sought a clear answer on whether Trump was wrong, while Oz at first tried to steer the conversation toward individual patient choice and the importance of consulting doctors.
Only after Brennan came back to the question a third time did the senior administration health official give a definitive response.
“The MMR vaccine is not a lethal vaccine,” Oz said.
The on-air exchange followed Trump’s signing, less than two weeks earlier, of an executive order that reshaped federal recommendations on childhood vaccines and urged that the three parts of the MMR vaccine be given separately.
At the signing, Trump claimed there was a “possibility” that the combined MMR shot could be “quite lethal,” though he did not provide evidence for the claim.
“Together there could be a possibility they are quite lethal,” Trump said. “Separately it looks like they are not at all lethal, but just very effective.”
Dr. Mehmet Oz said unequivocally that the MMR vaccine is ‘not a lethal vaccine’ after repeated questioning on Sunday
Earlier this month, President Trump claimed without evidence that there was a ‘possibility’ the combined MMR vaccine could be ‘quite lethal’
The comments immediately raised questions because separate measles, mumps and rubella vaccines are not currently available in the United States.
The combined MMR vaccine has been administered for more than four decades, and more than 800 million doses have been given across over 75 countries since 2021, according to research cited by Politico.
Brennan confronted Oz directly over Trump’s remarks on Sunday morning’s program.
‘The president twice said that the shot may be lethal,’ she told him. ‘Do you want to clarify that?’
Oz initially began: ‘We want the patients to make the —’
But Brennan interrupted and again pushed him to address the president’s specific assertion.
Rather than immediately saying whether the MMR vaccine was lethal, Oz turned to Trump’s broader position on patients seeing their doctors.
‘The president wants Americans – he said this many times – to get to the doctors as often as they can,’ Oz responded. ‘And it’s hard for parents to answer the questions.’
Brennan was not satisfied.
The MMR vaccine protects children against three highly contagious diseases – measles, mumps and rubella – in a single jab
CBS Face the Nation host Margaret Brennan repeatedly pressed Oz to address Trump’s claim that the combined MMR vaccine could potentially be ‘lethal’
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She returned to the practical problem with Trump’s suggestion that the three vaccines should be administered separately.
‘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?’
Only then did Oz categorically state the MMR jab was not a lethal one.
Oz’s declaration put one of the administration’s most recognizable health officials in the position of publicly correcting a claim made by the president weeks earlier.
He suggested that one of the administration’s concerns was whether parents feel able to raise questions about vaccination requirements.
‘The challenge we’re running into is that many states have not clarified that, and actually, it’s harder for parents to ask these difficult questions,’ he said.
The CMS chief also claimed that the MMR vaccines are available separately in other countries and argued that the broader debate should center on the ability of parents to question medical recommendations and vaccination requirements.
‘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 at an especially sensitive moment for US public health officials as measles cases have climbed to their highest level in 35 years.
Children receive shots at each visit on a schedule experts say is proven safe. Trump’s Executive Order doesn’t provide a new schedule. It directs agencies to review and adjust it
Earlier this month, President Trump signed an executive order to revamp federal childhood vaccine guidance and encourage states to reconsider school vaccine requirements
The Trump administration itself has encouraged parents to vaccinate their children against measles as cases have surged.
At the same time, vaccination rates among young children have continued to slip.
Figures released by the Centers for Disease Control and Prevention last week showed that 92.4 percent of US kindergarteners had been vaccinated against measles during the 2025-2026 school year.
That was down from 95.2 percent in 2019-2020.
The latest national rate is also below the roughly 95 percent vaccination level generally cited as necessary to achieve herd immunity against the extraordinarily contagious virus.
Measles can cause fever, cough, runny nose and a distinctive rash, but serious cases can lead to complications including pneumonia and encephalitis.
The MMR vaccine has been a cornerstone of childhood vaccination programs for decades.
Trump’s executive order earlier this month nevertheless called for a significant rethink of federal recommendations surrounding childhood vaccinations, including his push to separate the three MMR components.
But turning that proposal into practice presents an immediate obstacle: individual measles, mumps and rubella vaccines are not currently marketed separately in the United States.
