21 December 2017 - As bacterial meningitis season begins in West Africa this year, a convergence of factors is threatening the region with large outbreaks affecting millions. A new hyper-invasive strain of meningococcal meningitis serogroup C is circulating at the same time that an acute shortage of meningitis C-containing vaccine threatens to severely limit the region’s ability to minimize the number of persons affected. The risk of imminent large-scale epidemics is dangerously high.
Introductory-level online course on meningitis
This interactive online course on meningitis offers the most relevant scientific, technical and operational knowledge on managing infectious hazards through video lectures, presentations and self-tests. The module on meningitis focuses on the bacteria Neisseria meningitidis, as it can cause large-scale epidemics, and takes an hour to complete.
Meningitis is an inflammation of the meninges, the membranes covering the brain and spinal cord. It can be caused by a variety of organisms that include bacteria, fungi or viruses. It is a serious condition that can be life threatening.
Meningococcal meningitis is an acute form of bacterial meningitis caused by Neisseria meningitidis. Meningococcal meningitis is of particular importance as it has the potential to cause large epidemics.
Polysaccharide vaccines are used during a response to outbreaks, mainly in Africa:
• They are either bivalent (serogroups A and C), trivalent (A, C and W), or tetravalent (A, C, Y and W)
• They are not effective before 2 years of age
• They offer a 3 year protection but do not induce herd immunity.
Conjugate vaccines are used in prevention (into routine immunization schedules and preventive campaigns) and outbreak response:
• They confer longer-lasting immunity (5 years and more), prevent carriage and induce herd immunity.
• They can be used as soon as of one year of age
•Available vaccines include:
Tetravalent (serogroups A, C, Y, W)
Protein based vaccine, against N. meningitidis B. It has been introduced into the routine immunization schedule (one country as of 2017) and used in outbreak response.
- International Coordinating Group (ICG) on vaccine provision for meningitis
- The Meningitis Vaccine Project - frequently asked questions
- Prioritization tool for Meningitis A Conjugate Vaccine Introduction
Antibiotic prophylaxis for close contacts, when given promptly, decreases the risk of transmission.
• Outside the African meningitis belt, chemoprophylaxis is recommended for close contacts within the household.
• In the African meningitis belt, chemoprophylaxis for close contacts is recommended in non-epidemic situations.
Ciprofloxacin antibiotic is the antibiotic of choice, and ceftriaxone an alternative.
Geographical distribution and risk
Focus on the African meningitis belt
Risk of Nm C epidemics in Africa
Continuing risk of meningitis due to Neisseria meningitidis serogroup C in Africa: revised recommendations from a WHO expert consultation
Pneumococcal meningitis outbreaks in sub-Saharan Africa
- Laboratory methods for the diagnosis of meningitis caused by Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae
Managing meningitis epidemics in Africa