The meningococcal vaccine helps protect against a bacteria that can cause meningococcal disease. The infections are rare but can be very dangerous. 10-15 people out of 100 with meningococcal disease die. The meningococcal vaccine is the best way to protect teens and pre-teens from getting meningococcal disease. In Ohio, the meningococcal vaccine is required for entry into the 7th and 12th grades.