Pneumococcal pneumonia is an infection in the lungs caused by the bacterium Streptococcus pneumoniae.

Streptococcus pneumoniae bacterium can be found in the upper respiratory tract (nose, throat and windpipe) of healthy people; and can be spread between people through infected droplets in the air and by touching an infected person.

The pneumococcal bacteria can spread from the upper respiratory tract to the sinuses or ears where it results in relatively minor infections, however it can also spread to other parts of the body where it can cause serious disease. Some people, including the elderly and those with certain underlying health conditions, are at a higher risk than the rest of the population of contracting serious pneumococcal infections. The most common serious infection in adults caused by the pneumococcal bacteria is pneumococcal pneumonia, a serious lung infection which causes fever, coughing and difficulty breathing.

In addition to pneumonia, pneumococcal bacteria can cause a range of diseases including meningitis (infection of the areas surrounding the brain and spinal cord), septicaemia/ bacteraemia (blood system infection) and middle ear and sinus infections.