There are three types of exemptions:
You also have the option in most states to be exempted from vaccination or re-vaccination if you can show proof of existing immunity. You can go to a private laboratory for a blood test to determine if there are enough antibodies to prove existing immunity to a disease such as measles or whooping cough. A blood test that measures antibody levels can cost $55 or more, depending on the disease.
State vaccine requirements provides a map that shows what kind of exemption(s) each state accepts. You can also click on each state and it will provide additional information about filing your exemption.