Worldwide eradication of smallpox by live attenuated virus vaccination seems close at hand. This success has led to some optimism that the common childhood viral infections for which vaccines are available also can be eliminated.
Measles immunization has already resulted in a 90% reduction in the number of measles cases and complications. When properly administered, vaccine immunity that has been determined serologically remains stable.1 Yet Welliver et al, in the January Archives (137:39-41, 1977) showed that measles has certainly not been eliminated in the United States. Rand et al2 have reported other recent cases in adults and documented that the average age of patients with measles in four counties in northern California has risen from 7 to 11 years since the introduction of the vaccine in 1963. In all likelihood this trend will continue, resulting in a large group of susceptible young adults within the next five to