Invasive pneumococcal disease

Invasive pneumococcal infections are caused by the bacteria Streptococcus pneumoniae, also known as pneumococcus. It is a severe illness whereby the bacteria infect parts that are usually sterile (blood, brain tissue, etc.) Young children (<2 years old), the elderly (>65 years old) and people with immune disorders are the most vulnerable. 
Since the introduction of the pneumococcal vaccine the number of cases in Belgium has reduced.

What is an invasive pneumococcal infection?

Invasive pneumococcal infections (invasive pneumonia, septicaemia, meningitis etc.) are caused by pneumococcus (Streptococcus pneumoniae). These bacteria occur frequently in the upper respiratory tract without causing illness, but they can lead to mild respiratory infections and sometimes even penetrate into the underlying tissue or the bloodstream (invasive infections). Transfer of the bacteria occurs through direct contact or via droplets from the upper respiratory tract (for example through sneezing). 


Diagnosis occurs through the detection of the bacteria in blood, cerebro-spinal fluid (liquor), coughed-up mucus (sputum) or other bodily fluids. The bacteria can be stained and viewed under a microscope (gram preparation) or cultured in the laboratory. There is also a test that stains certain proteins of the bacteria (antigen test) and can be used on urine, among other things. 


The treatment consists of the administration of antibiotics.

High-risk groups and vaccination 

Young children (<2 years old), the elderly (>65 years old) and people with immune disorders have more risk of a severe infection. Vaccination against pneumococcal infections has been included in the basic vaccination schedule for children since 2007. The vaccine is also available for adults. For more information about risk groups and vaccination, see the Superior Health Council’s advice for children and adolescents and for adults.

Sciensano is responsible for surveillance of pneumococcal infections in Belgium. 

QR code

QR code for this page URL


Peer-reviewed publications

There are currently no publications associated to this health topic


There are currently no events associated to this health topic

Other sources of information

There are currently no external links associated to this health topic

In the media

There are currently no media associated to this health topic