The Republican senator’s childhood bout with the disease has informed his ardent support for vaccines amid increasing skepticism of them within his party.

Robert F. Kennedy Jr. is telling senators considering his nomination to lead the government’s health agencies he merely wants transparency about vaccines.

“There are so many things about RFK Jr. that would seem to make him a Democratic appointee instead of a Republican one — but so much of that is overshadowed by his anti-vaccine views, which resonate with Republicans after the Covid experience,” said Larry Levitt, executive vice president at the health policy think tank KFF.

Three of President Donald Trump’s most controversial Cabinet nominees faced sharp questions in the Senate during hearings Thursday from Democrats as well as several Republican senators in what amounted to the most direct skepticism from GOP senators over Trump’s nominees to date.

Intelligence nominee Tulsi Gabbard and health pick Robert F. Kennedy Jr. sparred with the senators, while FBI pick Kash Patel stayed on track.

Hassan sits on both the Senate health and finance committees, two GOP-steered bodies that must vote to send Kennedy’s nomination to the full Senate floor for confirmation. Kennedy met with the New Hampshire senator earlier this month in an effort to court her vote, per Politico.

Polio, a disease that can cause lifelong paralysis, has been eliminated from the U.S. Experts fear a resurgence if lifesaving vaccines are revoked under the new administration

Sen. Bill Cassidy of Louisiana has emerged as a central figure in the confirmation of Robert F. Kennedy Jr., President Donald Trump's nominee for health and human services secretary.

Sen. Bill Cassidy, the top Republican on the Senate Committee on Health, Education, Labor and Pensions, concluded Thursday's hearing by saying he was "struggling" with the nomination due to Kennedy's vaccine positions. Kennedy notably refused to say vaccines don't cause autism as he faced pointed question from lawmakers.

Lawmakers are set to grill Robert F. Kennedy, Jr., Tulsi Gabbard and Kash Patel, three of Trump’s most controversial Cabinet nominees.

Robert F. Kennedy’s first confirmation hearing Wednesday to become secretary of the Department of Health and Human Services was quickly interrupted by protesters over the Trump nominee’s vaccine positions. During his opening remarks, Kennedy said under oath that he is “not anti-vaccine”—but people standing in the back of the room weren’t convinced.