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Immunization: The Basics

Definition of Terms

Let's start by defining several basic terms:

Immunity: Protection from an infectious disease. If you are immune to a disease, you can be exposed to it without becoming infected.

Vaccine: A product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease. Vaccines are usually administered through needle injections, but can also be administered by mouth or sprayed into the nose.

Vaccination: The act of introducing a vaccine into the body to produce immunity to a specific disease.

Immunization: A process by which a person becomes protected against a disease through vaccination. This term is often used interchangeably with vaccination or inoculation.


Links to Basic Immunization Information

See also: Vaccines: The Basics


Related Information and Materials

  • The Parents' Guide to Childhood Immunizations
    68-page booklet introducing parents to all childhood diseases and the vaccines that can protect children from them
  • The Vaccines for Children Program
    The Vaccines for Children (VFC) Program offers vaccines at no cost for eligible children through VFC-enrolled doctors. Find out if your child qualifies. Vaccinating on time means healthier children, families and communities.


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