US Centers for Disease Control and Prevention criteria for evidence of immunity to measles
| At least one of the following: |
| Written documentation of adequate vaccinations including 1 or more doses of measles vaccine given after 12 months of age (preschool-age children) and adults “not at high risk” |
| Written documentation of 2 doses of vaccine for school-age children and adults at high risk: college students, healthcare personnel, and international travelers |
| Laboratory evidence of immunity |
| Laboratory confirmation of measles |
| Birth before 1957 |
Information from reference 4.