Live attenuated vaccines

Definition

Live attenuated vaccines are immunizations created from weakened forms of the pathogen they aim to protect against. These vaccines stimulate a strong immune response by mimicking a natural infection without causing the disease.

5 Must Know Facts For Your Next Test

1. Live attenuated vaccines typically provide long-lasting immunity with fewer doses.
2. They are usually not recommended for individuals with weakened immune systems due to the risk of causing an actual infection.
3. Examples include the measles, mumps, rubella (MMR) vaccine and the varicella (chickenpox) vaccine.
4. These vaccines require careful storage and handling since they contain live organisms that can lose potency if not kept under specific conditions.
5. Common side effects are mild and may include low-grade fever and mild rash as the body builds immunity.

Review Questions

• Why might live attenuated vaccines be contraindicated for immunocompromised individuals?
• What are some examples of diseases prevented by live attenuated vaccines?
• How do live attenuated vaccines differ in their storage requirements compared to other types of vaccines?

Related terms

Inactivated Vaccines: Vaccines made from killed pathogens that cannot cause disease but still provoke an immune response.

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

Herd Immunity: Protection from disease in a population when a large percentage is immune, reducing its spread.