Attenuated vaccine

Definition

An attenuated vaccine contains live pathogens that have been weakened so they cannot cause disease in healthy individuals. These vaccines stimulate a strong and lasting immune response.

5 Must Know Facts For Your Next Test

1. Attenuated vaccines are often used to protect against viral infections affecting the nervous system, such as polio and measles.
2. These vaccines can provide lifelong immunity with just one or two doses.
3. They work by mimicking natural infection, thus stimulating a comprehensive immune response including both humoral and cellular immunity.
4. Attenuated vaccines must be stored carefully as the live pathogens can revert to a virulent form if not handled properly.
5. Individuals with compromised immune systems generally should avoid live attenuated vaccines due to the risk of serious infection.

Review Questions

• What are the advantages of using an attenuated vaccine over an inactivated vaccine?
• Why is it important to store attenuated vaccines under specific conditions?
• In what scenarios might an attenuated vaccine not be recommended?

Related terms

Inactivated Vaccine: Contains pathogens that have been killed and cannot cause disease but still elicit an immune response.

Immunogenicity: The ability of a substance, such as an antigen or epitope, to provoke an immune response.

Adjuvant: A substance added to a vaccine to enhance the body's immune response to the provided antigen.