I suspect that prior to this pandemic most venues hosting a birthday party for a kindergartener would frown upon any guest attending who is currently infected w

I suspect that prior to this pandemic most venues hosting a birthday party for a kindergartener would frown upon any guest attending who is currently infected with a contagious disease or who is not vaccinated against any highly infectious diseases experiencing a local outbreak at that time. This is not "private medical history" in any sense other than that any guest is free to not attend if they don't wish to share this information.