Long before the COVID-19 pandemic, Robert F. Kennedy Jr. was building up a following with his anti-vaccine nonprofit group, Children’s Health Defense, and became one of the world’s most influential spreaders of fear and distrust around vaccines.

Putting Robert F. Kennedy Jr. in charge of the Department of Health and Human Services would fulfill Donald Trump’s promise to let him “go wild on health.”

The nearly $2 trillion agency administers health-insurance programs for millions of Americans, approves medications and oversees vaccine safety.