This doctor-senator who backed RFK Jr. now faces a fight for his job — and his legacy

The ambitious liver doctor would go just about anywhere in his home state to give people the hepatitis B vaccine.

Bill Cassidy offered jabs to thousands of inmates at Louisiana's maximum-security prison in the early 2000s. A decade before that, he set up vaccine clinics in middle schools, a model hailed nationally as a success.

"He got that whole generation immunized in East Baton Rouge," said Holley Galland, a retired doctor who worked with Cassidy vaccinating schoolchildren.

About the same time, a lawyer and environmental activist with a famous last name was starting to build the loyal anti-vaccine coalition that, two decades later, would move President Donald Trump to nominate him as the nation's top health official. 

Today, a year after now-Sen. Cassidy warily cast the vote that ensured Robert F. Kennedy Jr.'s ascension to that role, the Louisiana Republican's life’s work - in medicine and in politics - is unraveling. 

Newborn hepatitis B vaccination rates in the U.S. had plunged to 73% as of August, down 10 percentage points since a February 2023 high, according to research published in JAMA last month. In December, the Centers for Disease Control and Prevention's Advisory Committee for Immunization Practices - remade by Kennedy - voted to revoke a two-decade-old recommendation that all newborns get the shot.

The next month, Trump endorsed U.S. Rep. Julia Letlow, a Cassidy challenger in what's shaping up to be a competitive Republican Senate primary. Letlow's foray into politics began in 2021 when she took the seat won by her husband, left vacant after he died from covid.

KFF Health News made multiple requests for comment from Cassidy over three months. His staff declined to make him available for an interview or provide comment. Letlow's campaign did not respond to requests for comment.

Rise of the skeptics

As the May primary nears, some Louisiana doctors are worried they've begun a long trek down a dark road when it comes to vaccine-preventable diseases.

Last year, on the day Kennedy was sworn in a thousand miles away in Washington, Louisiana's health department stopped promoting vaccines, halting its clinics and advertising. Its communications about an ongoing whooping cough outbreak in the state have nearly ceased. It took months for the state to announce last year that two infants had died from the illness. A Louisiana child's death from the flu was confirmed this January, and a couple of cases of measles were reported last year.

Spokespeople for the Louisiana Department of Health did not respond to questions.

"It's so hard to see children get sick from illnesses that they should have never gotten in the first place," said Mikki Bouquet, a pediatrician in Baton Rouge. "You want to just scream into the void of this community over how they failed this child."

As anti-vaccine forces have taken hold of the state and federal health departments, Cassidy has lamented the consequences.

"Families are getting sick and people are dying from vaccine-preventable deaths, and that tragedy needs to stop," he wrote on social media last fall.

But while it is Cassidy's duty as chairman of the Senate's Health, Education, Labor, and Pensions Committee to conduct oversight of the health department, Kennedy has appeared before the committee just once since he was confirmed.

The secretary speaks at a "regular clip" with Cassidy, said Department of Health and Human Services spokesperson Andrew Nixon.

Kennedy's department has elevated Louisiana vaccine skeptics. The state surgeon general who terminated Louisiana's vaccine campaign, Ralph Abraham, was named deputy director of the CDC. (He left the role in February.) And Kennedy handpicked Evelyn Griffin, a Baton Rouge OB-GYN who later replaced Abraham as the state surgeon general, for an appointment to ACIP. Griffin has suggested the covid vaccine had dangerous side effects for young patients.

Research has shown that serious side effects from the vaccinations are rare and that the shots saved millions of lives during the pandemic.

Cassidy "has really not had an outspoken chorus of policy supporters" when it comes to inoculating people, said Michael Henderson, a professor of political communication at Louisiana State University. "There's not a lot of political stakes in doing that in Louisiana if you're a Republican."

Louisiana Gov. Jeff Landry reprimanded Cassidy after the senator called for the state's health department to ease access to covid shots.

"Why don't you just leave a prescription for the dangerous Covid shot at your district office and anyone can swing by and get one!" the Republican quipped on X in September.

On 'eggshells' in the exam room

On a sunny February afternoon, as Carnival floats were readied to parade the streets of New Orleans, pediatrician Katie Brown approached a basement apartment on a well-child visit. Cowboy boot pendants dangled from her ears, and a pack of diapers were clutched tightly in her arms.

The patient, a toddler who waved at the sight of visitors, was up to date on her immunizations. But when Brown suggested a covid vaccine, the girl's mother quickly declined, noting she had never gotten the shot either.

Many of Brown's young patients - seen through Nest Health, which offers in-home visits covered by Louisiana's Medicaid program - are current with their vaccines. Brown said home visits make parents more comfortable immunizing their children, but she's still spending more time these days explaining what they're getting in those shots.

"After covid vaccines, that's when some people just decided, 'I don't know if I trust vaccines, period,'" she said.

Across the state, vaccination rates have declined since the pandemic, falling short of the levels scientists say are required to achieve herd immunity for some deadly diseases, including measles. About 92% of Louisiana's kindergartners have had the recommended two doses of the measles, mumps, and rubella vaccine.

The New Orleans Health Department has tried to step up with a $100,000 immunization campaign of its own, with clinics and billboards, during this year's flu season, said Jennifer Avegno, the department's director.

But the state's absence is felt. Other parishes across Louisiana have not taken similar action, leaving doctors largely on their own to promote immunizations.

"I'll say that with certainty," Avegno said. "It's been a blow to not have a statewide coordination."

A day after Brown's home visit, a mother in Baton Rouge shook her head when Bouquet offered a flu shot for her 10-year-old daughter in an exam room.

In the waiting room, parents could thumb through a handmade book that offers scientific facts to counter fears about vaccines. A laminated guide placed in each exam room explained the benefits of each recommended immunization.

Bouquet said she's experimenting with ways to educate parents about vaccines without seeming overbearing. She still hasn't figured out a surefire formula. Some parents now shut down any vaccine talk, and she worries others skip scheduling appointments to avoid the topic entirely.

"We're having to walk on eggshells a bit to determine how to get that trust back," Bouquet said. "And maybe these discussions can come up in future visits."

Pro-vax, pro-anti-vaxxer

Children's Health Defense, the nonprofit that Kennedy helmed, worked to erode vaccine trust during the pandemic - falsely claiming, for instance, that covid shots cause organ damage and that polio vaccines were at fault for a rise in the disease. The organization also sued the federal government over the mRNA-based covid shots, hoping to get their emergency authorizations from the Food and Drug Administration revoked.

When Kennedy came before Cassidy's committee in January 2025 as Trump's nominee for health secretary, the senator-doctor saw risks if the prominent anti-vaccine lawyer was confirmed.

Cassidy described a time years ago when he loaded an 18-year-old onto a helicopter to get an emergency liver transplant. The young woman had acute hepatitis B, an incurable disease that is spread primarily through blood or bodily fluids and can lead to liver failure.

It was "the worst day of my medical career," he said, addressing Kennedy at the witness table in front of him. "Because I thought, $50 of vaccines could have prevented this all."

Cassidy started in politics in 2006 as a state senator, winning election to the U.S. House two years later. When he first ran for the U.S. Senate, in 2014, he charmed Louisiana voters with campaign ads showing him dressed in scrubs and a white lab coat, talking about his work with Hurricane Katrina evacuees and patients at Baton Rouge's public hospital.

But some Republicans soured on Cassidy after he voted to convict Trump on an article of impeachment charging him with inciting the Jan. 6, 2021, insurrection at the U.S. Capitol.

The impeachment vote has hampered Cassidy's reelection bid this year in a state where Trump captured 60% of the vote in 2024.

"Cassidy has things that are associated with his name: the impeachment vote in 2021," Henderson said.

Cassidy's loyalty to Trump was tested again with Kennedy's nomination. Cassidy said he endorsed Kennedy after extracting pledges that he wouldn't tinker with the nation's vaccination program.

But since taking office, Kennedy has largely ignored those promises, and Cassidy hasn't publicly rebuked him.

Former Texas congressman Michael Burgess served for years with Cassidy in the House, where they were founding members of the GOP Doctors Caucus, started in 2009. He said Cassidy's discomfort with some of Kennedy's actions is palpable.

"You could hear some of the pain in Sen. Cassidy's voice when he was addressing that the secretary wanted to drop the birth dose of hepatitis B," Burgess said. "You got cases to nearly zero on hepatitis B. It was painful to him to think about taking this away from the population."

Retired Baton Rouge nurse practitioner Elizabeth Britton has switched her party affiliation so she can vote in the closed Republican primary for Cassidy, with whom she vaccinated inmates decades ago.

She doesn't quite understand the "mess" in Washington that resulted in the senator voting to confirm a vaccine critic.

Watching Kennedy and others promulgate doubts about shots she once administered has made her "profoundly sad" and "angry," she said, but most of all worried.

"It puts a pit in my stomach, because I know the consequences of people not getting the vaccine," she said.