Vaccines are intended to prepare your immune system to fight off infections and prevent disease. But do you know how they do it exactly?
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The Human Immune System and Infectious Disease
The human immune system is essential for our survival in a world full of potentially dangerous microbes.
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Passive Immunization
You don't always need to be exposed to a pathogen, or part of it, to be immune. Sometimes, an infusion of antibodies from a donor is enough to give you immunity.
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Different Types of Vaccines
There are several types of vaccines, each created in a different way and for a different purpose.
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Viruses and Evolution
Pathogens are always evolving, adapting to the pressures put on them by their environment. This could be a problem.
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Disease Elimination and Eradication
Eradication means the disease is no longer found anywhere in the world. Only two diseases have been eradicated: one human and one in animals.