I rarely travel anywhere. I caught pinworms and Ascaris as a kid, before I ever even left the state.
I don't know doctors insist on perpetuating the myth that Americans don't have any worms. But anytime you mention pinworms to people with kids, somebody will say "Oh yes. My kids had them. They caught them at school!"
I don't think it's right to blame pinworms infestations on kids and schools.
American adults are in denial. Their pinworms are so deeply embedded in their tissues they are developing hemmorrhoids and fissures, and they want to pretend the kids are bringing them home from school. Mullarkey.
Why does the America public have an electric fence constructed around the anal sphincter? Out of shame? Elitist Pride? Or What?
It isn't possible to eradicate them by pretending they don't exist.