Health Secretary Robert F. Kennedy Jr. on Sunday crashed out and hurled attacks at CNN host Dana Bash as she pressed him over his vaccine skepticism in a contentious 21-minute interview on "State of Union."

During one heated moment, the conspiracy theorist questioned whether Bash could point to a study showing that children were protected by the COVID-19 vaccine and if it "did more harm than good."

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(Note: Millions of lives have been saved as a result of vaccination efforts, per some estimates, and a CDC report issued under President Donald Trump in December found that vaccinations against COVID-19 led to "substantially lower risks" for children during the prior respiratory virus season.)

Kennedy — after Bash claimed that research shows misinformation led vaccine hesitancy and, thus, could've prevented the hundreds of thousands of deaths — accused the host of "talking nonsense."

"You are saying nonsense! You are saying something that you cannot show me a single study that says that," Kennedy said.

"I am not saying nonsense," Bash replied.

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"You are talking —," Kennedy began.

"Excuse me! Excuse me!" Bash interjected.

"Somebody told you —," Kennedy chirped. "Cite me the study!"

"Let me — no, what studies are you talking about? You're actually talking about studies that actually don't exist," responded Bash, who told Kennedy that the clash was "not productive."

Earlier in the interview, Kennedy accused Bash of "absolute press malpractice" and being "part of the problem" in what he described as a dismantling of constitutional rights that occurred during the pandemic. 

"Your job is a fierce skepticism toward authority and you weren't doing that, you were beating up on people who were dissenting," Kennedy declared.

"Do you want to sit here and attack me, or do you want to have conversations about public health?" Bash asked.

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Later in the interview, Bash referred to Kennedy as "one of the leading voices questioning vaccine efficacy" and asked if he accepted "some responsibility" for the ongoing measles outbreak.

"Absolutely not," said Kennedy, who made misleading claims about the safety and efficacy of the vaccine last year.

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After Kennedy claimed he "never questioned the efficacy of the MMR vaccine (and later took Bash's suggestion that he use the interview to call on parents to get their children vaccinated for measles), he promoted Trump's unfounded claims linking use of Tylenol in pregnancies to autism.

"You're rolling your eyes, Dana," Kennedy remarked. 

"I am, because I don't want to have you use our air to say this," she replied.

Watch Bash's full interview with Kennedy in the video below.

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