It’s a common, misleading refrain in anti-vaccine circles: Childhood vaccines may be unsafe because few if any have been tested in placebo-controlled trials before being approved. But that claim misunderstands the vaccine safety testing process and takes advantage of a narrow definition of a placebo, scientists told us.
“Not a single childhood vaccine on the schedule has ever been through a double-blind placebo-based trial prior to licensure,” Del Bigtree, a prominent activist with ties to Health and Human Services Secretary Robert F. Kennedy Jr., said at a March 9 conference that billed itself as being about a “massive epidemic” of vaccine harm. “It is now a known fact that they were never done. No placebo trial anywhere in sight,” Bigtree went on to say.
“I don’t believe all vaccines are bad. I’ve never said that. What I’ve said is they should be safety tested,” Kennedy said, noting that the government is funding the development of a universal flu vaccine and cancer vaccines. (In a 2023 podcast, he said that “no vaccine” is safe and effective, and later denied making those remarks.)
