SEM micrograph of an encapsulated bacteria (Pneumococcus).

Examples of encapsulated bacteria

• Haemophilus influenzae type B (Hib)^[1]
• Streptococcus pneumoniae (pneumococcus)^[1]
• Neisseria meningitides (meningococcus)^[1]
• Group B streptococcus (GBS)^[1]
• Salmonella typhi^[2]

Role in disease

Many encapsulated bacteria are pathogens that lead to a significant amount of morbidity and mortality.^[3]

Asplenia

People that lack a spleen, functionally (as in sickle cell disease^[4][5]) or anatomically (due to a splenectomy or congenital absence), have been shown to be more susceptible to these pathogens. Therefore, it is standard medical practise to recommend vaccination.

People with asplenia are commonly offered vaccines against Neisseria meningitis, Haemophilus influenzae, and Streptococcus pneumoniae; these vaccines can be remembered with the mnemonic: NHS.

Children

Young children do not have the ability to make antibodies to polysaccharide and are, therefore, more susceptible to encapsulated bacteria.^[3] This is especially so for children between 6months and 1year old,where maternalantibodies are depleted and endogeneous synthesis is not perfected yet.

See also

• Conjugate vaccine

References

1. ↑ ^{a b c d}
2. ↑ Lee CJ, Lee LH, Koizumi K. Polysaccharide Vaccines for Prevention of Encapsulated Bacterial Infections: Part 1. Infect Med 19(3):127-133, 2002. Partial Free Text.
3. ↑ ^{a b} Full Free Text.
4. ↑
5. ↑