Vaccines - How We Know

Behind the Scenes with Vaccines
Vaccines are medications that are usually injected to help prevent you from getting certain diseases. Remember "getting your shots?" Perhaps you got shots for whooping cough or diphtheria. Some vaccines contain proteins (called antibodies) that give immediate protection. But most vaccines are designed to stimulate the body to develop its own antibodies, and that can take up to a few weeks to happen.

Vaccines for certain diseases actually contain the infectious agent, but it is weakened by culturing it in some other system, such as eggs or tissue culture. The goal in vaccine manufacturing is to make the infectious organism weak enough so that it won't cause the disease but strong enough so that it will activate the body's immune system.

Once the immune system is activated by the disease agent, proteins called antibodies are generated to fight the disease. The antibodies are "programmed" specifically to fight that particular infectious agent. The original antibodies that are generated in response to a vaccination eventually go away, but the immune system has a "memory" and can make new ones later on if challenged by the same disease agent.

Booster shots can be used to trigger an even bigger response than only one vaccination would provide. Many vaccinations have to be repeated every year or so, although for some diseases you can be protected for a lifetime by a single injection.

Diseases of the Immune System

Examples include:

"auto-immune" diseases such as rheumatoid arthritis and fibromyalgia in which the immune system loses the ability to recognize normal proteins, and the immune system begins to attack its own body
AIDS (acquired immunodeficiency syndrome), a fatal venereal disease that attacks the immune system and for which there is no vaccine or cure