Overview
The MenB vaccine protects against invasive disease caused by Neisseria meningitidis serogroup B.
- Targets meningococcal meningitis and meningococcemia.
- Designed specifically for serogroup B, which is not covered by MenACWY vaccines.
- Used in infants, adolescents, and high-risk groups in several countries.
Why a Separate Vaccine for Serogroup B
- The serogroup B capsule closely resembles human neural cell adhesion molecules.
- This similarity makes traditional polysaccharide-based vaccine development difficult.
- Therefore, MenB vaccines are protein-based rather than polysaccharide-conjugate vaccines.
Type of Vaccine
MenB vaccines are recombinant protein vaccines.
- Contain outer membrane proteins or vesicles from the bacterium.
- Stimulate immune response against specific surface antigens.
- Do not rely on capsular polysaccharide.
Mechanism of Action
- Induces antibodies against key surface proteins of serogroup B bacteria.
- Prevents bacterial invasion into bloodstream and meninges.
- Helps reduce risk of severe invasive disease.
Indications
Recommended for:
- Infants in countries with routine immunisation schedules.
- Adolescents and young adults, particularly in outbreak settings.
- Individuals with complement deficiencies.
- Persons without a functional spleen.
- Laboratory workers exposed to meningococcal isolates.
Dosage Schedule
- Administered intramuscularly.
- Usually given in two or three doses depending on age and vaccine type.
- Booster doses may be recommended for high-risk individuals.
Schedules vary by national immunisation policy.
Efficacy
- Provides protection against circulating strains of serogroup B.
- Effectiveness depends on match between vaccine antigens and circulating strains.
- Does not protect against serogroups A, C, W, or Y.
Safety Profile
- Generally safe and well tolerated.
- Common side effects include injection site pain, fever, fatigue and irritability in infants.
- Serious adverse events are rare.
Public Health Significance
- Serogroup B is a major cause of meningococcal disease in several regions.
- Rapid disease progression makes vaccination critical.
- Important in outbreak control and prevention of severe neurological complications.
The MenB vaccine represents an advanced immunological approach targeting protein antigens to prevent invasive meningococcal disease caused by serogroup B, complementing the broader protection offered by MenACWY vaccines.
