A person sneezes a lot of bacteria into the air. The person sneezes, and covers his mouth. The sneezers either wipes his hands on his pants or uses tissue paper. Bacteria transfer from the person’s hand to objects. Bacteria can spread via sexual interaction. They also ride produce and water from one place to another.
How can microbes be carried from person to person? – http://wiki.answers.com/Q/How_can_microbes_be_carried_from_person_to_person