Meningococcal meningitis is an uncommon bacterial infection that attacks the brain and spinal cord membranes. Bacteria called Neisseria meningitidis cause meningococcal disease and there are 5 leading types: serogroups A, B, C, W, and Y. Vaccination can help protect against all 5 of these serogroups.
 
Neisseria meningitidis is transmitted via respiratory secretions, which is more likely to occur due to close or prolonged contact, such as kissing or living in the same household. Nasopharyngeal carriage rates of N. meningitidis are highest in adolescents and young adults. 

Meningococcal disease caused by the 5 leading serogroups (A, B, C, W, and Y) can progress from flu-like symptoms to death in as little as 24 to 48 hours. Despite prompt treatment, 10% of cases are fatal and 20% of cases can result in permanent sequelae.