This study will lay the foundation for determining the underlying reasons for lack of immunity to mumps that led to the 2006 mumps outbreak on college campuses in the Mid West, and it will assess the potential for similar outbreaks of measles and rubella. A total of 70 to 80 college students (age 18 to 22) on the Emory campus (or nearby college campuses or the community) will be assessed for antibodies to measles, mumps or rubella by drawing a one-time blood sample. Their medical records will be verified for documentation of immunization with MMR vaccine prior to enrollment in the study. If a study volunteer is found to not have MMR immunity, they will be offered an MMR-II vaccine. For this group, additional blood specimens will be obtained.

No additional description needed.

Inclusion Criteria:

• Ability and willing to provide an informed consent
• Documented receipt of MMR-II vaccination in childhood
• Not pregnant

Exclusion Criteria

• No history of HIV infection.
• Immunocompromised health status due to HIV infection, cancer, diabetes, liver, lung or kidney diseases, autoimmune diseases, history of splenectomy.
• Use of immunosuppressive medications within last 2 to 3 months (oral or parenteral corticosteroids or cytotoxic medications)
• Medical conditions that require the use of immunosuppressive medications
• Received blood or blood products within the last 30 days
• Any vaccines received in the last 30 days

Subjects for this study will be 18-22 year olds recruited from Emory University's student population who have received two age-appropriate doses of the MMR-II vaccine.