Robert F Kennedy Jr, the US health secretary, on Sunday told American parents that they should get their children vaccinated against measles, as the surge in infections has reached numbers not seen in the past 35 years.

Kennedy, a leading vaccination skeptic who has spent years amplifying misinformation about vaccines, including the shot that protects against measles, mumps and rubella (MMR), made his call in the course of a contentious interview with CNN’s State of the Union on Sunday morning.

His remark came as the incidence of measles crossed a milestone – the US has now officially recorded 2,371 confirmed infections so far this year, surpassing the total tally in 2025 of 2,289.

Taken together, the past two years have seen more measles infections in the US than the rest of the 21st century combined. The last time a greater number of measles cases were recorded in a single year was in 1991.

Kennedy’s statement was extracted from him by Dana Bash, CNN’s host, who invited him to use his “bully pulpit” to talk directly to parents as the new school year approached. She urged him to tell families that they should vaccinate for measles “because it is safe and it will help them save their children’s lives”.

The health secretary replied: “Parents should get their children vaccinated for measles. A measles vaccine is effective, it stops measles in about 97% of the cases. People should get vaccinated.”

Later in the interview he added that people should also get the combined measles, mumps and rubella vaccine, the main protection against the disease that has been a particular target of the anti-vaccination movement.

The health secretary’s call for parents to vaccinate their children for measles contrasts starkly with the many years in which Kennedy has been a leading proponent of misinformation questioning the efficacy and safety of vaccinations. Even since he became the country’s top health official, he has depicted a measles vaccination as a personal choice and claimed inaccurately that the power of the inoculation is waning.

The call also comes late in the day, given the rate at which measles is spreading in the US. The 37 new measles outbreaks that have already been recorded this year are putting the US in danger of losing the measles elimination status that it has held since 2000.

Kennedy continues to shrug off criticism that his work as a prominent vaccine skeptic, both before and after he entered the Trump administration, has exacerbated the problem. Asked whether he took any responsibility for the measles surge, he said: “Absolutely not.”

He went on to blame the outbreaks on religious communities who eschew vaccines and on global health conditions.

Any hope that Kennedy’s measles statement might indicate a change of heart were dashed in the rest of the CNN interview in which he turned combative. Batting off questions from Bash, the health secretary responded with personal attacks.

He accused the CNN host of “saying nonsense”, “repeating like a parrot” and “making assertions you can’t support”. In one especially demeaning remark he said Bash had become “flustered”.

“I’m not flustered at all,” she asserted in a calm voice. “I am frustrated because you are the HHS secretary and you are talking about things that lead to vaccine hesitancy in this country.”

In a further comment dripping with condescension, Kennedy told Bash “you probably don’t understand this because you’re not a scientist”.

The journalist riposted: “But you’re not, either.”

Kennedy used the CNN exchange to spread further misinformation about other aspects of public health. He claimed that both respiratory syncytial virus (RSV) that is a major cause of infant mortality and Lyme disease were caused by manipulation of germs in laboratories.

The suggestion has been contradicted by decades of scientific evidence that suggest they both have natural roots. RSV was initially identified in the 1950s, two decades before such experimentation, known as “gain-of-function” research, started.

During the interview, Kennedy repeated unfounded claims that there was a link between Tylenol use during pregnancy and autism, and poured doubt on the efficacy of vaccines to protect children against Covid-19.

Speaking to CNN’s State of the Union later in the show, Ashish Jha, who advised Joe Biden’s White House on its Covid response, said he was heartened to hear Kennedy say that “every kid in America should be getting the MMR vaccine”. But he added that much else of what the health secretary had said “just isn’t true”.

Jha said that the dramatic rise in measles cases on Kennedy’s watch was not coincidental. “The administration has not done enough to promote vaccines. It has not done enough to highlight the harms that come from measles.”