Meningococcal A+C vaccine is a more advanced vaccination against epidemic meningococcal meningitis. The vaccine is not only against the group A bacteria of epidemic meningomyelitis, but also against the group C bacteria of epidemic meningomyelitis, and has immunity to both groups of bacteria. After freeze-drying, the vaccine is more stable and has a shelf life of two years. The vaccine is mainly administered to children over two weeks of age and adult patients.