1. Vaccines
What are they?
How do they work?

2. What is immunity?
Capacity to resist a disease that you have been exposed to by being able to fight it off.

3. Immunity
Measles
Polio

4. Immune Response
Invaded 1st time, production of antibodies to defeat it. (few days, or weeks)
Immune system ”remembers” how to produce antibodies for infection
Antibodies fight agent, destroyed quickly

5. What is a vaccine?
Prepared substance that is able to immunize an organism against one or several diseases.
Attenuated or weakened infectious agents, Not strong enough for full blown disease.
Infectious agent defeated quickly because our immune substance “remembers”
Oral: polio, rabies, cholera

6. Administered
Injected
Orally

8. How are vaccines made? Need a cell culture of the infectious agent
Cultured cells are treated to make them harmless
The method chosen to do this will either make the vaccine:
Isolate the actual cell from organism like a person who has the disease. Incubate in favorable conditions (feed the bacteria). Grow it on a petri dish and then you have many.

9. 1. Live vaccine
has been chemically treated to make it lose its ability to cause disease.
Infectious agent still alive, but lost ability to cause disease.
New technology uses genetic transformation to make it harmless.

10. 2. Inactive Vaccines
Developed using only part of the infectious agent.
These antigens are isolated, chemically treated, then mixed with chemicals to improve shelf life.
Does not contain any live infectious agents.
Transforming genome of bacteria, yeasts or animal cells can produce antigens in large quantities.
The antigen is not the harmful part, the invader is

11. Which one is better? Live or inactive?
Live vaccines cause a stronger immune response
But,
sometimes, the attenuated (weakened) infectious agent in the live vaccine can regain its virulence
Virulence = harmfulness
sometimes, live vaccines may cause the disease instead of immunizing against it