We often think only about how vaccines might protect us from
infection, however, they can also protect those around us from
getting sick. Researchers have found that vaccines are one of
the safest and least expensive ways of reducing illness and
death in a community. Some of the most important public health
triumphs have been in vaccine development, such as the small pox
and polio vaccines. This is an introduction to vaccines, how
they work in our body and the different kinds of vaccines
available today. The immune system is our defense system for
recognizing and eliminating infections or "foreign invaders." It
is made up of a network of specialized cells and organs. When
the immune system is functioning properly, it can tell the
difference between foreign invaders and the bodys own cells and
will create a response to eliminate or neutralize the invader.
There are different types of immune responses, those we were
born with (innate immunity) and those we learn (acquired
immunity). When we get sick, some of th