Conjugate vaccines only use a small part of a bacterium linked to carrier protein.
There are some bacteria that are coated with sugar molecules (not the tasty kind) called polysaccharides. These sugars, which we call the bacteria’s antigens, are what the body makes antibodies to. They also increase the bacteria’s ability to cause disease. Young children are especially susceptible to getting sick from these types of bacteria.
Scientists are able to take part of the sugar coating and use it in the vaccine so that the body creates immunity to the sugar coating. Should the bacteria enter the body, then antibodies will recognize the sugar coating, and keep the bacteria from causing disease.
These conjugate vaccines also have antigens or toxoids, often from the same bacteria, linked to the sugar molecules. Linking the sugar to a stronger protein is another way to ensure complete protection, because the immune system has to respond to both the sugar and the protein.
Examples of conjugate vaccines:
Bacterial:
- Haemophilus influenzae type B (Hib) Vaccine
- Pneumoccocal Vaccine
- Meningococcal Vaccine
- The Children’s Hospital of Philadelphia (CHOP). www.chop.edu
- The Centers for Disease Control and Prevention (CDC). www.cdc.gov
- National Institute of Allergy and Infectious Disease. National Institutes of Health. www.niaid.nih.gov
- The history of Vaccines. The College of Physicians of Philadelphia. www.historyofvaccines.org
- Vaccine Healthcare Centers Network. www.vhcinfo.org