What to know about Robert F. Kennedy Jr., Trump's pick for health secretary

President-elect Donald Trump 's plan to appoint Robert F. Kennedy Jr., to lead the Health and Human Services Department will put a prominent vaccine skeptic at the helm of the nation's sprawling public health apparatus.

A scion of a famous Democratic dynasty, Kennedy made a name in his own right as an environmental attorney who successfully took on large corporations including DuPont and Monsanto.

But over the past two decades, he's increasingly devoted his energy to promoting claims about vaccines that contradict the overwhelming consensus of scientists.

Trump would have Kennedy lead a massive Cabinet agency that oversees everything from drug, vaccine and food safety to medical research and the social safety net programs Medicare and Medicaid. He said before the election he would give Kennedy free rein over health policy.

Here's a look at Kennedy and the agency he'll be tasked with leading:

Kennedy defies scientific consensus on vaccines and other issues

He took over the anti-vaccine group Children's Health Defense and built it into a juggernaut during the pandemic. His activism helped him build a loyal following that he's leveraged in his political pursuits.

While there are rare instances when people have severe reactions to vaccines, the billions of doses administered globally provide real-world evidence that they are safe. The World Health Organization says vaccines prevent as many as 5 million deaths each year.

He wants to eliminate liability protections for drug companies.

Even before Trump was elected, Kennedy said he would recommend water agencies stop adding fluoride to drinking water. Fluoride strengthens teeth and is viewed as one of the biggest public health successes of the past century.

He made a variety of other claims not backed by science, such as questioning whether HIV causes AIDS and suggesting antidepressants lead to school shootings.

Children's Health Defense, currently has a lawsuit pending against a number of news organizations, among them The Associated Press, accusing them of violating antitrust laws by taking action to identify misinformation, including about COVID-19 and COVID-19 vaccines. Kennedy took leave from the group when he announced his run for president but is listed as one of its attorneys in the lawsuit.

Kennedy has promised to take a serious look at those who work for HHS and its agencies, including the Food and Drug Administration, the National Institutes of Health and the Centers for Disease Control and Prevention.

He is especially focused on putting an end to the ''revolving door'' of employees who have previous history working for pharmaceutical companies or leave government service to work for that industry, his campaign communications manager Del Bigtree told the AP last month. Bigtree is also an anti-vaccine organizer.

He said he wants to fire 600 employees at the National Institutes of Health, which oversees vaccine research, and replace them with 600 new employees.

Many of the scientists and researchers who work at the NIH are not political appointees, which makes firing them abruptly more difficult. Nevertheless, Kennedy made the promise at the Genius Network Annual Event in Scottsdale, Arizona, according to a video first obtained by ABC News.

''We need to act fast, and we want to have those people in place on Jan. 20, so that on Jan. 21, 600 people are going to walk into offices at NIH and 600 people are going to leave,'' Kennedy said, according to a video of his remarks posted on YouTube.

Kennedy is a scion of a famous dynasty

Kennedy's father was Attorney General Robert F. Kennedy, brother of President John F. Kennedy. Both men were assassinated.

Kennedy originally ran in the Democratic primary against President Joe Biden before deciding to launch an independent bid. He then suspended that campaign earlier this year and endorsed Trump, who has repeatedly praised Kennedy, promised him influence in a future administration, and vowed to ''Make America Healthy Again.''

The GOP base has eagerly welcomed Kennedy since he joined forces with Trump, an embrace Kennedy never received from the Democratic Party. His anti-vaccine activism has alienated him from much of his famous family.

He's known for run-ins with dead animals — and a dead brain worm

He once retrieved a bear that was killed by a motorist and left it in New York's Central Park with a bicycle on top, sparking a mystery that consumed the city in 2014. A photo showed Kennedy with his fingers in the bear's bloodied mouth, a mock grimace on his face and an apparent bloodstain on his pantleg.

He denied eating a dog after a friend shared a photo with Vanity Fair showing Kennedy dramatically preparing to take a bite of a charred animal; Kennedy said it was a goat.

And a federal law enforcement agency opened an investigation after Kennedy allegedly cut off the head of a dead whale and took it home two decades ago. The National Marine Fisheries Service ended the probe a short time later.

Big changes could be in store for FDA and drugmakers

Kennedy's nomination is certain to be opposed by the pharmaceutical lobby in Washington, which relies on the predictability of FDA's science-based rules to bring new medicines to market.

Instead, Kennedy has suggested barring drugmakers from advertising on TV, a multibillion-dollar enterprise that accounts for most of the industry's marketing dollars. He's also proposed eliminating fees that drugmakers pay the FDA to review their products, allowing the agency to hire extra scientists to speed up their work. Replacing those funds would require billions in new appropriations from the federal budget.

In a post last month to the social media platform X, Kennedy vowed to end FDA's ''aggressive suppression'' of a host of unsubstantiated therapies, including psychedelics and stem cells as well as discredited COVID-era drugs like ivermectin and hydroxychloroquine.

In recent interviews, Kennedy has also suggested clearing out ''entire departments'' at FDA, including the one responsible for nutrition standards.

The nomination has scrambled political allegiances

The Kennedy pick was condemned by public health officials and some congressional Democrats.

But it also won some bipartisan support.

''Finally, someone to detox the place after the Fauci era,'' Sen. Rand Paul, R-Kentucky, wrote on the social media platform X, referring to Anthony Fauci, the former leading public health official who has been demonized by people opposed to vaccines and the government's response to COVID-19.

Jared Polis, the Democratic governor of Colorado, said he was ''excited'' about Kennedy's appointment and said he would shake up HHS and the FDA.