In an era when each new year seems to bring with it a new health scare, whether it be hantavirus, bird flu, or swine flu, it's natural to wonder, "Is pneumonia contagious?" Because pneumonia strictly just means an inflammation of the lungs, usually caused by infection, the answer is slightly complicated. You can develop pneumonia from a contagion that you got from another person who did not have pneumonia, and you can pass the germs causing your pneumonia to a third person who may or may not develop pneumonia from them. In essence, the viruses, bacteria and fungi that may lead to an inflammation of the lungs are contagious.
The most common cause of viral pneumonia is the influenza virus. You may develop pneumonia from an influenza strain you caught from another person who never showed any symptoms of the flu, let alone pneumonia, and you may pass that virus on to a third person who also doesn't develop pneumonia from the virus, but the virus, the root cause of your pneumonia, is contagious.
Bacterial pneumonia is the most common type of pneumonia among healthy adults. It is caused by the infection of the lungs by a wide variety of bacteria, the most common being streptococcus pneumoniae. While you can develop bacterial pneumonia without being exposed to someone else with bacterial pneumonia or any other infection, the bacteria that cause bacterial pneumonia are contagious. The contagion is contained in the water droplets you cough or sneeze out during the course of the illness. If another person becomes contaminated, they may develop bacterial pneumonia, another form of bacterial infection, or their immune systems may simply render the bacteria harmless.
Fungal pneumonia results from a lung infection caused by an endemic or opportunistic fungus. Because a healthy immune system can usually deal with most common fungi, it most often occurs in people with compromised immune systems. However, like viral and bacterial pneumonia, the contagion will be contained in the infected person's secretions, and could end up infecting someone else.
Receiving an annual flu shot will help protect you from pneumonia caused by the influenza virus. A swine flu vaccination is also recommended, as swine flu can also lead to pneumonia. Frequent hand washing in warm soapy water and avoiding using other people's utensils and towels can also help.