A form of bacteria called Chlamyophila pneumoniae infection can result in pneumonia and other respiratory tract illnesses. One reason for lung infections that occur outside of a hospital is C. pneumoniae. Not everybody who is exposed to C. pneumoniae, however, gets pneumonia.
When someone coughs or sneezes, tiny respiratory droplets are produced that carry the bacteria and can transmit the sickness. The bacteria and droplets are then inhaled by other persons. Additionally, if someone touches their mouth or nose after coming in contact with something that has a sick person’s droplets on it, they may become ill.