Meningococcal diseases are infections caused by the bacteria called meningococcus.
The most important meningococcal diseases are meningococcal meningitis and meningococcemia. Meningitis is an infection of the lining of the brain and the spinal cord caused by various viruses, parasites and bacteria. Meningococcal meningitis is caused by the meningococcal bacteria. If a person appears more ill than with the usual cold or flu, it is important to visit your doctor. Meningococcemia is the infection of the blood caused by the meningococcal bacteria.