There has been some speculation that vaccines can cause autism, and thousands of people have filed claims with the Vaccine Injury Compensation Program at the Department of Health and Human Services. On February 12, 2009, a special court ruled against over 4,800 claims, saying that autism in those cases was not caused by vaccines.CNN: Vaccine didn't cause autism, court rules (February 12, 2009)

1. The first vaccine in use was cowpox in 1796
2. Vaccines rely on the human body's immune response
3. Child vaccinations prevent illnesses that are severe in childhood
4. Vaccines contain weakened germs that triggers the immune systemMedlinePlus: Immunization
5. The body fight the germs, and afterward it "remember" them, which builds the body's immune system to that germMedlinePlus: Immunization
6. Vaccines work the same way people become immune to diseases by having it onceMedlinePlus: Immunization
7. Common vaccines are those given to prevent measles, mumps, rubella, hepatitis B, polio, diphtheria, tetanus
8. Some vaccines are required before children are allowed to attend schoolMedlinePlus: Immunization
9. Some vaccines work best when given at a specific age