Pneumococcal disease is caused by a common bacterium called Streptococcus pneumoniae (also known as pneumococcus). It targets different parts of the body to cause a range of diseases including pneumonia, otitis media (ear infection), septicaemia (blood poisoning) and meningitis.
Many healthy people carry the pneumococcal bacteria in the back of the nose or throat, but without causing them to suffer the disease. It is thought that over 50% of under 5's carry the bacteria, although this number falls to less than 10% in the over 20's.
How does pneumococcal disease spread?
The bacteria are carried in the nose and throat with infection occurring in a small proportion of these individuals. The bacteria is transmitted by droplets in a similar way to colds or flu viruses but usually requires either frequent or prolonged close contact.This can be a particular problem in places where people spend time in close contact with each other such as schools, hospitals, and care homes. And, just like colds and flu, the spread is most common in the winter months.
Is pneumococcal disease serious?
Pneumococcal disease can cause a whole range of conditions and these can vary from being mild through to very severe. Sometimes the consequences can be very serious, including hearing loss, brain damage or may lead to fatality. Generally the outlook for people with pneumococcal infections is good, however, there is a risk of complications in the very young, the elderly and those with other serious conditions.
Which parts of the body are affected by pneumococcal disease?
It can generally affect the body in two ways:
Non-invasive pneumococcal disease is where the bacterium spread through the respiratory tract to cause conditions such as pneumonia, and otitis media.
Invasive pneumococcal disease occurs when areas of the body such as the blood or central nervous system are infected causing serious and potentially life-threatening conditions including septicaemia, meningitis and pneumonia.