Long before the COVID-19 pandemic, Robert F. Kennedy Jr. was building a following alongside him anti-vaccine nonprofit group, Children’s Health Defenseand becoming one of the most influential spreaders of fear and mistrust around vaccines.

Now President-elect Donald Trump says he will nominate Kennedy to lead the Department of Health and Human Services, which regulates vaccines.

Kennedy has come a long way disproves the idea that vaccines cause autism. He also promoted other conspiracy theories like this one COVID-19 may have been ‘ethnically targeted’ to spare Ashkenazi Jews and the Chinese people, comments he later said were taken out of context. He did it repeatedly brought up the Holocaust when discussing vaccines and public health mandates.

No medical intervention is without risk. But doctors and researchers have proven that the risks of disease are generally far greater than the risks from vaccines.

Vaccines have been proven safe and effective in laboratory tests and in real-world use on hundreds of millions of people over decades—they are considered among the most effective public health measures in history.

Kennedy insisted it was not anti-vaccinesaying he only wants vaccines to be rigorously tested, but has shown opposition to a wide range of immunizations. Kennedy said in a 2023 podcast interview that “There is no safe and effective vaccine” and told Fox News that he still believes in idea long since dismantled that vaccines can cause autism. In a 2021 podcast, he urged people to “resist” CDC guidelines on when children should receive vaccines.

“I see someone on a hiking trail carrying a small child and I say, you better not vaccinate,” Kennedy said.

That same year, in a video promoting an anti-vaccine sticker campaign organized by his nonprofit, Kennedy appeared on screen next to a sticker that read “IF YOU’RE NOT AN ANTI-VAXER, DON’T BEWARE.”

The World Health Organization has estimated that global immunization efforts have saved at least 154 million lives in the last 50 years.

One study of verified Twitter accounts from 2021researchers found that Kennedy’s personal Twitter account was the largest “spreader” of vaccine misinformation on Twitter, responsible for 13 percent of all retweets of misinformation, more than three times the second most retweeted account.

Traveled states incl Connecticut, California and new york to lobby or sue for vaccination policies and has traveled the world to meet with anti-vaccine activists.

Kennedy also lined up business and special interest groups like the anti-vaccine chiropractorswho saw profit in cutting off a small slice of the larger health care market while spreading false or dubious health information.

An Associated Press investigation found that a California chiropractic group had donated $500,000 to Kennedy’s Children’s Health Defense, about one-sixth of the group’s fundraising that year. Another AP investigation found that he was listed as an affiliate for an anti-vaccine video serieswhere it was ranked in the Top 10 for the series’ “Overall Sales Ranking”.

His group co-published a number of anti-vaccine books that were debunked. One, called “Unknown Cause,” is built upon false premise that sudden deaths of young, healthy people are increasing due to mass administration of COVID-19 vaccines. Experts say so rare medical emergencies are not new and they did not become more widespread.

An AP book review found that dozens of people in it died of known causes unrelated to vaccines, including suicide, choking while intoxicated, overdose and allergic reaction. One person died in 2019.

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