Pseudomonas is most often spread by direct contact. Although it is possible to catch pseudomonas by inhaling the germ from the air coughed out by an infected person, this is unusual. A person infected with pseudomonas may infect another person at any time. However they are more likely to infect another person when they have a flare up. Another key element for someone to become infected with pseudomonas is that their immune system be weakened in some way, such as overwhelming stress or illness.
Pseudomonas is found in many things including soil, plants, and animals. Although it is weak and cannot harm healthy people, it is still resistant to most treatment in patients that are weak. It can also withstand a more harsh envirorment than most other bacterias. It is what we call an "Oportunistic" type bacteria. It can be in the body but not multiply freely because the immune system may be strong. However, once the immune system is comprimised, it jumps at the opportunity to devide and multiply. It is predominantly found in hospital envirorments and is responsible for many nosicomial infections there (hospital acquired infection). Pseudomonas is also the main infection found in Cystic Fibrosis patients and people with AIDS.
Contracting Pseudomonas is like getting the common cold. If someone coughs in your face, if you shake hands, and them wipe your nose, open wounds, etc. It can infect anywhere in your body. Predominantly the lungs. But again, your immune system needs to be very weak for it to make you symptomatic. Otherwise, you have nothing to worry about really.
Andy, RRT, CPFT