Meningococcal disease refers to any illness caused by the Neisseria meningitidis bacteria. They include meningitis - infections of the lining of the brain and spinal cord - and bloodstream infections, namely bacteremia and septicemia. These diseases are often serious or deadly and are transmitted through the exchange of respiratory and throat secretions like saliva1.
1 DC.gov. 2021. Meningococcal disease. [online] Available at: https://www.cdc.gov/meningococcal/. Accessed 29 September 2021.