Senator Bill Cassidy, the Republican chairman of the US Senate health committee, blamed the Trump administration’s vaccine-skeptical approach for ‌recent measles deaths in Pennsylvania and challenged Donald Trump’s pick for surgeon general to directly state that vaccines do not cause autism on Wednesday.

Cassidy, a Louisiana physician who chairs the panel, said three people in Pennsylvania had died of measles, with a fourth death under review, because ​of misinformation and misguided policies. His remarks come as the US grapples with its worst measles outbreak in over three decades.

“To suffer from any disease is awful, but to suffer one which is avoidable, that’s even worse,” Cassidy said, adding that the country needs health leaders “who make decisions based on science, not politics or ideology”.

The senator said that the outbreak would be “a terrible legacy for this administration”.

The committee is ​currently considering the Trump-picked Chris Klomp for deputy secretary of health and human services, Nicole Saphier for surgeon general and Timothy Westlake to ⁠lead the Substance Abuse and Mental Health Services Administration.

Saphier notably avoided mentioning vaccines directly in her opening remarks, instead expressing her Make America Healthy Again bona fides.

“I have long believed that we spend too much time and resources treating chronic disease after it takes hold, and not enough time helping Americans reduce their risk before illness begins. And unfortunately, we’re seeing the consequences of that imbalance right now: rising cancer rates in people under 50, cardiovascular disease that remains the number one killer, but also is largely preventable in lots of cases,” Saphier said.

Cassidy pushed Saphier about whether she would tell parents concerned about the measles, mumps and rubella (MMR) vaccine that it does not cause autism.

“I’m so sensitive to this because I’ve had wriggle room from people sitting there … who later use that wriggle room to do things which are quite contrary?” Cassidy said, referring to the various promises that Robert F Kennedy Jr made to the top Republican in his confirmation hearing, only for the health secretary to renege on several occasions.

“Would you feel comfortable communicating with clarity … Is the MMR vaccine extremely lethal, as the president said?” Cassidy asked Saphier.

The nominee for surgeon general said that she “cannot speak to what the president has said” but went on to say: “I do not believe the MMR vaccine to be lethal. I believe the MMR vaccine is our greatest tool for combating measles.”

Saphier, who is a practising radiologist and Fox News contributor, added: “The best tool we have to combat these infections to save the most lives and to also create population herd immunity is vaccination against the MMR. I appreciate the president is trying to reach vaccine-hesitant people who are wanting more answers or who are concerned that there are too many doses.”

Cassidy, however, remained unconvinced by the president’s public health strategy. “I’m not sure that you reach people who are vaccine hesitant by feeding into untruths,” the chair said.

Last month, the senator denounced Trump’s “crazy, stupid” claims about the safety of the combined MMR vaccine for undermining faith in immunization.

Cassidy previously voted to confirm Kennedy as health secretary, despite disagreements over how to combat vaccine skepticism.

The senator said that Kennedy, who has pushed the discredited theory that vaccines cause autism for decades, had promised him that the Centers for Disease Control and Prevention (CDC) “will not remove statements on their website pointing out that vaccines do not cause autism”.

After Kennedy became health secretary, however, the Autism and Vaccines page on the CDC website was altered to undermine that scientific consensus. An asterisk was added to the headline “Vaccines do not cause Autism”, which leads to a footnote pointing out that “the root causes of autism” remain unknown.