Anti-vaccine statement by Geert Vanden Bossche?

It's a grift. He founded a company that's going to make an NK-based vaccine, and wrote this to stir up doubt about the current vaccines so that someone might buy his. He's never published a single paper about vaccines in the past, and hasn't published anything at all since 1994. He's been making the rounds doing video interviews on antivaxxer websites and podcasts all month.

As to the "science" behind his "open letter", here's one of many rebuttals: https://www.deplatformdisease.com/blog/addressing-geert-vand...

If you came across this letter and were interested enough to forward it on, you need to take a step back and consider whether you've gotten yourself into a misinformation bubble. This information isn't circulating anywhere reputable. Wherever you learned of it is probably feeding you other misinformation that's just as wrong and dangerous.