WASHINGTON — Sen. Bill Cassidy, the powerful chair of the Senate Health, Education, Labor, and Pensions Committee, said that if Robert F. Kennedy Jr. carries his previously held anti-vaccine rhetoric into his post as the prospective Secretary of the U.S. Department of Health and Human Services and people die as a result, it will "cast a shadow over President Trump’s legacy."

"Now, let’s be political. I’m a Republican. I represent the amazing state of Louisiana and as a patriotic American, I want President Trump’s policies to succeed in making America and Americans more secure, more prosperous, healthier," Cassidy said Thursday while leading Kennedy's confirmation hearing.

"But if there is someone that is not vaccinated because of policies or attitudes you bring to the department and there is another 18-year-old who dies of a vaccine-preventable disease, helicoptered away, God forbid dies, it’ll be blown up in the press."

Cassidy was one of several senators who was skeptical about Kennedy's stance on vaccinations, also noting Kennedy has changed his tune on the subject during the hearing.

"You are telling us in the Senate this week that you support vaccines. What are you going to tell them?" Cassidy said. "Now, your past of undermining vaccine confidence with unfounded or misleading arguments is concerning to me."

If Kennedy's nomination reaches the full Senate, he could lose no more than three votes among Republicans, who hold 53 posts. If senators split 50-50, Vice President J.D. Vance would hold the tie-breaking vote, as he did with Defense Secretary Pete Hegseth last week.

Cassidy, a medical doctor, shared a story of an 18-year-old patient brought to his hospital with hepatitis B who had to undergo an "invasive, quarter-of-a-million-dollar surgery" that would continue to cost $50,000 in hospital bills annually.

"As I saw her take off, I was so depressed, a $50 vaccine could have prevented this all," Cassidy said. "Ever since, I have tried to do everything I can so that I do not ever have to see another parent lose their child due to a vaccine-preventable illness."

Cassidy said that he has been in contact with the prospective top health official and that the two agree on many health matters.

"We need to address hyper-processed foods and reduce obesity, which leads to other chronic diseases and shorter lifespans. This will be a priority in the Committee and I look forward to collaborating if you are confirmed," the senator said.

During Kennedy's hearing, he also struggled to answer questions about Medicare and Medicaid, the Associated Press reported. The AP also noted that senators from both sides of the aisle grilled Kennedy on his vaccine stance.

"Can I trust that that is now in the past? Can data and information change your opinion, or will you only look for data that supports your predetermined conclusion?" Cassidy said. "This is imperative if you have the responsibility to restore trust in our public health institutions as the nation’s top health official."