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
- Why immunize?
Learn how getting vaccinated can protect your grandchildren, prevent epidemics, and eliminate diseases and their serious consequences.
- Brief overview of adult and childhood vaccine-preventable diseases and vaccines
Read about the serious diseases that cause long-term illnesses, hospitalization, and even death, and which can be prevented by vaccines.
- 10 things a parent should know about immunizations
Includes how many vaccine doses your child needs, the importance of keeping records, side effects, etc.
- How immunity works: types of immunity
Learn the difference between the two basic types of immunity: active and passive.
- Common questions
Find answers to common questions about immunization.
- What would happen if we stopped vaccinations?
See how diseases that are rare today could once again become common—and deadly—if vaccination coverage does not continue at high levels.
- Life-cycle of an immunization program
See how a successful immunization program can lead to a temporary increase in disease. Follow the evolution of a disease, from a time when there was no vaccine untilit is eradicated.
- Vaccine availability timeline
Dates when vaccines first became available.
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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