I wrote:

"In a single instance [stepping on a nail, children] inject themselves with more bacteria than all the vaccinations in a lifetime."

That I am sure of, by the way. See this excellent article about vaccination hysteria:

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Paul Offit, the hero of the vaccination wars, showed that a person can safely receive 100,000 times the dose of a vaccination. Whereas if you got 100,000 times -- or even 100 times -- the dose of bacteria from a puncture wound, you would be dead in no time.