What is a vaccine?
When germs enter the body, the immune system recognizes them as foreign substances (antigens). The immune system produces the right antibodies to fight the antigens.
Vaccines contain weakened versions of a virus or versions that look like a virus (called antigens). This means the antigens cannot produce the signs or symptoms of the disease, but they do stimulate the immune system to create antibodies. These antibodies help protect you if you are exposed to the virus in the future.
Vaccines not only help keep your child healthy, they help all children by stamping out serious childhood diseases