"PF Riley" wrote
Hep B is transmitted via body fluids; ergo, diligent parents will make
sure their infant/child isn't engaging in unprotected sex, sharing
needles, or
being exposed to the body fluids of others (of unknown hep B status) in
other ways.
So they'll just go to the library instead the playground at recess?

Is there more unprotected sex at recess than at the library?