Neisseria meningitidis
Overview
Also known as the meningococcus, Neisseria meningitidis is a Gram-negative aerobic encapsulated bacteria associated with bacterial meningitis. It is commensal and can be found asymptomatically in the nasopharynx. There are multiple serogroups, depending on its capsule’s antigens, the most significant being A, B, C, W, and Y.
The spleen is crucial for protection against encapsulated bacteria, therefore hyposplenism (e.g. splenectomy) can increase the risk of severe infection, characterised by rapidly deteriorating sepsis.
Neisseria gonorrhoeae
Overview
Neisseria gonorrhoea is a Gram-negative aerobic diplococcus found in purulent genital discharge that causes gonorrhoea.
