Determine status or, with paired sera, aid in the diagnosis of recent infection.
Measles (rubeola) is caused by a paramyxovirus, and despite vaccination programs has had several recent local epidemics. Revaccination appears to be of greater value at 11 to 12 years of age than at four to six years of age. Serologic study can be useful in establishing that an individual has effective immunity subsequent to vaccination. In many individuals detectable immunity does not persist.