A rare infectious disease of the nervous system caused by the bacterium Streptococcus pneumoniae, which is commonly part of the bacterial flora colonizing the nasopharyngeal mucosa. The disease is clinically characterized by typical symptoms of acute leptomeningitis, like fever, headache, neck stiffness, vomiting, and clouding of consciousness. It is frequently fatal and, in surviving patients, often accompanied by long-term sequelae, especially focal neurological deficits, hearing loss, cognitive impairment, and epilepsy. [from
ORDO]