RFK Jr. has suggested vaccines caused 1918 Spanish flu pandemic at least twice [View all]

For years, internet users have shared a rumor about U.S. Health Secretary Robert F. Kennedy Jr. falsely claiming that vaccines caused the 1918-1919 influenza pandemic known as the Spanish flu.

One Facebook post (archived) with around 105,000 reactions at the time of this writing featured a photo of Kennedy with the caption:

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Examples of the claim also appeared in posts on social media platforms including X (archived), Threads (archived) and Reddit (archived), as well as in reporting by The New York Times and Rolling Stone.

Snopes readers searched our site and wrote messages to the newsroom asking if Kennedy really said vaccines, or vaccine research, caused the 1918 pandemic that killed an estimated 50-100 million people worldwide, according to a 2002 estimate (a more recent estimate in 2018 placed the death toll lower at around 17.4 million).

https://www.snopes.com/news/2025/04/01/rfk-vaccine-spanish-flu-pandemic/