When we had our 1st kid in 90 this old Waitress told my wife to let the kids play and get dirty drink out of others kids drinks, take a bite out of this or that its no biggy, if they want to play and ones sick who cares. It will keep them from getting sick in the future.
SIL had a kid, The ripped out the carpet ,put concrete in the back yard, because of the possibility of asma (sp). he couldnt play with other kids toys at there house, Birthday parties were a hoot to go to NOT! he would pick up a toy and mom would come running over and wash it, then give it to him etc etc. kids almost 30 and get sick just with someone walking by him, hes on tons of meds too.
Seen this with many kids over the years clean freaks always get sick, normal kids not as much.