Basics
Pneumonia is caused by pathogens of various types, such as bacteria, fungi or viruses attacking the lung tissue. In response, there is inflammation of the deeper parts of the lungs, as well as the air sacs (aleveoli) and/or the connective tissue that lies between them. As a result, swelling and increased blood flow occur in the affected area of the lung.
A certain type of bacteria (Streptococcus pneumoniae = Pnemococcus) is found in about 30 to 60 percent of all pneumonia cases in patients of younger age. In industrialized countries, pneumonia is the most common infectious disease leading to death. Worldwide it is in third place.
In Germany, there are approximately 10 new cases of Community Acquired Pneumonia (AEP) per 1000 people. Most pneumonias are of bacterial origin. The risk group includes mainly infants, young children and the elderly. For people whose immune system is otherwise intact and who are healthy, pneumonia does not pose a great danger. It usually heals without lasting consequences.
For older people, however, as well as children and people with a weakened immune system, pneumonia can have fatal consequences. Pneumonia that originates and develops in the hospital poses a particularly great danger.