For most kids chicken pox was a week off from school, some itching, and a couple of scars. And since it is so contagious (because it is contagious before you feel sick) nearly everyone got it as a kid. But it can and does kill adults who contract it.
But it can and does kill adults who contract it.
Chickenpox deaths peaked in the early 1970's at about 140 deaths per year.
By comparison (click), that's about the same number as killed by falling coconuts every year.
And I'd rather be killed by a coconut than live (or die) impaired for the remainder of my days with guillain-barre.