Between 13 different serogroups of N. meningitidis, identified according to the capsular polysaccharide’s antigenic structure, only 5 (A, B, C, W-135 and Y) are clinically relevant and responsible for 90% cases of meningococcal invasive disease. In Italy, serogroup B is the principal cause of invasive meningococcal disease [1]. There are two types of tetravalent vaccines for serogroups A, C, W-...
