Serum antibodies to capsular polysaccharide vaccine of group A and C Neisseria meningitidis in military recruits in Italy.

: In this study we evaluated, by a standard bactericidal assay, the antibody response to the meningococcal group A and C polysaccharide vaccine used for the immunization programme of the Italian military recruits, compulsory by law since 1987. The percentage of responders, those who developed a four-fold increase in the bactericidal titre to polysaccharide A and C, was 96% and 98%, respectively. No significant side effects were observed after vaccination.