PREVENTION STRATEGY FOR INVASIVE MENINGOCOCCAL DISEASE. The prevention strategy for invasive meningococcal disease (IMD) includes vaccination and antibiotic prophylaxis in the vicinity of a case. IMD is unpredictable, difficult to recognize at an early stage, and very severe, with a mortality rate about 10 %, and 20 to 25 % of survivors suffering from permanent disabling sequelae that impact their quality of life. Meningococcal conjugate vaccines against A, C, ACWY provide both individual and collective protection due to their effect on meningococcal carriage. Protein-based vaccines against serogroup B have been developed. These vaccines demonstrate effectiveness in the field in children and adolescents with acceptable tolerance. Immunization programs have been adapted to recent epidemiologic modifications. Immunization with the ACWY meningococcal conjugate vaccine has replaced meningococcal C vaccination and is now mandatory for infants, along with the meningococcal B vaccine. The ACWY meningococcal vaccine is recommended for adolescents aged 11-14 years, with a catchup program for those aged 15 to 2 5 years.