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Medical Term:

Streptococcus pneumoniae


a species of gram-positive, lancet-shaped cocci and diplococci frequently occurring in chains; cells are readily lysed by bile salts. Virulent forms are enclosed in type-specific polysaccharide capsules, the basis for an effective vaccine. Normal inhabitants of the respiratory tract, and the most common cause of lobar pneumonia, they are the most common causative agents of meningitis, and pneumonia worldwide, and also cause otitis media, sinusitis, and other infections. It is the type species of the former genus Diplococcus.

Synonym(s): Fraenkel pneumococcus, pneumococcus, pneumonococcus

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.