General Information | Surveillance & Epidemiology | Vaccination
Pneumococcal infections are defined as invasive or non-invasive according to the body site they affect. Invasive pneumococcal disease (IPD) is caused by infection of normally sterile sites e.g. blood and cerebrospinal fluid (CSF). IPD is a major cause of morbidity and mortality, especially amongst the very young, the elderly, and those with impaired immunity. Non-invasive forms of the infection commonly cause middle ear infection (otitis media), exacerbations of bronchitis, and pneumonia. As with most infectious respiratory diseases, the numbers of cases of pneumococcal infection peak in winter. Many people (up to 50%) carry pneumococci in their nose and throat without developing serious infection.
Streptococcus pneumoniae is the bacterium responsible for causing pneumococcal infection. It is characterised by its outer coat (capsular polysaccharide), and in a process known as serotyping, different strains can be distinguished. There are about 90 different types of pneumococci, about a quarter of which cause serious illness.
Department of Health
Health Protection Management of Pneumococcal disease clusters