Opinion: Vaccines saved lives. DeSantis threatens that progress.

Vaccines saved millions of lives in the pandemic, and the mRNA technology was rolled out in record time. It counts as a massive success and might help fight other diseases, too. Nonetheless, populist Florida Gov. Ron DeSantis (R) last week demanded a grand jury investigate “criminal or wrongful activity in Florida” involving the “development, promotion and distribution” of coronavirus vaccines. As public opinion shows vaccine hesitancy is growing, Mr. DeSantis’s move is not only absurd but also dangerous. Vaccines work. A mathematical model, based on country-level data, found they directly saved some 15.5 million lives worldwide in the first year they were available, and millions more indirectly.