Vaccinations/ Immunization

Streptococcus pneumoniae, Neisseria meningitidis. and Haemophilus influenzae  are encapsulated bacteria whose polysaccharide capsule components can be  covalently bound to protein carriers and used as vaccine antigens.

The protein  carriers convert the polysaccharides from T-cell independent to T-cell dependent  antigens.

Approved carrier proteins include:

• mutant nontoxic diphtheria toxin.,
• Neisseria meningitidis outer membrane protein complex, and
• tetanus toxoid.

It is important to be aware of vaccines which are of the live-attenuated type as these may pose a risk to immunocompromised patients.

The globally recommended vaccines discussed in this lesson fall into four main types.

• Live attenuated vaccines
• Inactivated whole-cell vaccines
• Subunit, recombinant, polysaccharide, and conjugate vaccines
• Toxoid vaccines

The main types of vaccine are as follows:

Live attenuated

• Bacterial
• BCG