Efficacy of a single-dose MenA conjugate vaccination in immunocompetent children (9 to 24 months of age) against serogroup A meningococcal disease

• Population : Immunocompetent children aged 9–24 months
• Intervention: Single-dose MenA conjugate vaccine (5 µg dosage)
• Comparison: No MenA vaccination
• Outcome : Serogroup A meningococcal disease

What is the scientific evidence concerning the efficacy of a single dose of MenA conjugate vaccine (versus no Men A vaccination) against serogroup A meningococcal disease in immunocompetent children aged 9–24 months?