WASHINGTON (AP) — Robert F. Kennedy Jr.'s long record of doubting the safety of childhood vaccinations persisted as a flash point for him Thursday in a confirmation hearing where senators, including a key Republican, shared intensely personal details about the impact vaccine skepticism had on their lives.

Robert F. Kennedy's nomination will put Republican lawmakers' loyalty to the test, as the former Democrat holds a range of unorthodox positions that could alienate both conservatives and liberals.

Vaccination bills are popping up in more than 15 states as lawmakers aim to potentially resurrect or create new religious exemptions from immunization mandates, establish state-level vaccine injury databases or dictate what providers must tell patients about the shots.

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.

As Robert F. Kennedy Jr. faced skeptical senators Thursday in the second day of his confirmation hearing to lead the department of Health and Human Services, Sen. Bill Cassidy confronted Kennedy about vaccines.

Robert F. Kennedy Jr. transferred ownership of the trademark application in December and its abbreviation — MAHA — to an LLC managed by Del Bigtree.

The hearings were packed to capacity with protesters and fans, while the spillover crowd hung out in hallways and overflow rooms.

That drew quick pushback from Democratic Sen. Ron Wyden of Oregon — and ensuing back and forth between him and Kennedy. Wyden pointed out the health secretary nominee has previously claimed there's “no safe” vaccine. Wyden also quoted from Kennedy's books, which say that parents have been “misled” on the measles vaccine.

WASHINGTON (AP) — Robert F. Kennedy Jr.’s anti-vaccine advocacy is outside the mainstream. His previous statements on abortion could alienate Republicans. But a new poll finds that not all of his controversial health goals are unpopular — in fact, at least one has broad support among Democrats and Republicans.

Robert F. Kennedy Jr. is distancing himself from his anti-vaccine work as he seeks to become the leader of the nation’s top health agency under President Donald Trump, according to government ethics documents released on Wednesday.

The Texas legislature is debating bills that advocates say could give individuals more choice in whether they vaccinate themselves and their children.

Robert F. Kennedy Jr. ‘s bid to be the nation’s top health official is uncertain after a key Republican joined Democrats to raise persistent concerns over the nominee’s deep skepticism of routine childhood vaccinations that prevent deadly diseases.