“We all have mouths teeming with bacteria and viruses even when we seem well,” notes Denver pediatrician Nancy Broady Lataitis, M.D. “A bad germ might not cause symptoms for another 24 hours, as it incubates. And while you may have antibodies to that germ that keep you from getting sick, the family member who just took a sip might not have the same protection. Do the very best you can to avoid sharing drinks, utensils, or objects that come into contact with saliva. And please don’t pop that pacifier in your mouth to ‘clean it’ before giving it to your baby!” Dr. Lataitis also recommends sending kids to school with their own water bottle so they can avoid the drinking fountain.