Meningococcal vaccine: A vaccine to prevent meningococcal infection, including meningococcal meningitis, an inflammation of the membranes that cover the brain and spinal cord. Meningococcal infection is caused by the bacterium Neisseria meningitidis and can be fatal.
A meningococcal vaccine was licensed by the US Food and Drug Administration in 1982. The vaccine contains 50 µg of purified polysaccharide from each of four serogroups (A, C, Y, and W-135) which account for a large share of all cases of meningococcal infection. The vaccine is given routinely to all military recruits and is recommended for high-risk groups such as persons with asplenia (no spleen) and those who plan to travel to areas where there is an epidemic of meningococcal disease.
College students and military recruits who live in dormitories and barracks, respectively, are unusually susceptible to meningococcal meningitis. Meningococcal disease strikes almost 4 of every 100,000 college freshman in dorms. The CDC has recommended that college freshmen therefore be vaccinated against this type of bacterial meningitis. College students who live on campus have triple the risk of acquiring meningococcal infection compared with their peers who live off-campus. Among the factors are the relative crowding associated with dormitory residence, alcohol-related behaviors, and exposure to tobacco smoke. The same factors make young adults who are military recruits at higher risk for meningococcal meningitis and provide the basis for recommendations that they, too, receive the vaccine.