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Meningococcal vaccine

Meningococcal vaccine refers to any of the vaccines used to prevent infection by Neisseria meningitidis.

Different versions are effective against some or all of the following types of meningococcus: A, B, C, W-135, and Y.

Meningococcal vaccines are between 85 and 100% effective for at least two years.

Meningococcal vaccines decrease in meningitis and sepsis among populations where they are widely used.

Meningococcal vaccines are given either by intramuscular injection or subcutaneously.

Pregnancy category C

Routes of administration:

Intramuscular (conjugate)

Subcutaneous (polysaccharide)

The World Health Organization: countries with a moderate or high rate of disease or with frequent outbreaks should routinely vaccinate.

In countries with a low risk of disease, they recommend that high risk groups should be immunized.

Vaccines effective against all four types of meningococcus are recommended routinely for teenagers and others who are at high risk.

Such meningococcal vaccines are generally safe, but some people develop pain and redness at the injection site.

Use in pregnancy appears to be safe.

Allergic reactions occur in less than one in a million doses.

Neisseria meningitidis has 13 clinically significant serogroups, classified according to the antigenic structure of their polysaccharide capsule.

Almost all cases of disease are due to six serogroups, A, B, C, Y, W-135, and X.

Presently there are three vaccines available in the US to prevent meningococcal disease, all quadrivalent in nature, targeting serogroups A, C, W-135, and Y:

two conjugate vaccines (MCV-4), Menactra and Menveo.

one polysaccharide vaccine (MPSV-4), Menomune

Menactra has FDA approval for use in children as young as 9 months.

Menveo has FDA approval for use in children as young as 2 months.

Meningococcal polysaccharide vaccine. Menomune, is the only meningococcal vaccine licensed for people older than 55.

Menomune’s duration of immunity is three years or less in children aged under 5 because it does not generate memory T cells.

Boosters for Menomune results in a diminished, not increased, antibody response, and are not recommended.

With polysaccharide vaccines, such as Menomune does not produce mucosal immunity.

People can still become colonized with virulent strains of meningococcus, and no herd immunity can develop with Menomune.

Menomune is suitable for travelers requiring short-term protection, but not for national public health prevention programs.

Menveo and Menactra contain antigens conjugated to a diphtheria toxoid polysaccharide–protein complex, resulting in anticipated enhanced duration of protection, increased immunity with booster vaccinations, and effective herd immunity.

There is only limited evidence that any of the current conjugate vaccines offer continued protection beyond three years.

The vaccine, Menhibrix, that can be given to infants as young as six weeks old prevents disease caused by Neisseria meningitidis serogroups C and Y and Haemophilus influenzae type b.

A vaccine called MenAfriVac has the potential to prevent outbreaks of group A meningitis, which is common in sub-Saharan Africa.

Vaccines against serotype B meningococcal disease have proved difficult to produce, as the capsular polysaccharide on the type B bacterium is too similar to human neural adhesion molecules to be a target.

Current meningoccocal meningitis vaccines are not known to protect against serogroup X N. meningitidis disease.

Side effects of meningococcal vaccines:

Common side effects include pain and redness around the site of injection.

A small percentage of people develop a mild fever.

Menveo and MenHibrix (combination of meningococcal and Hib vaccines) are approved for use in children as young as 2 months if indicated.

Menactra is approved only for children at least 9 months of age.

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