Should All Children Receive Two Measles Vaccinations?
Because of the rising incidence of rubeola, we tested all our patients who were vaccinated prior to 15 months of age and those vaccinated after 15 months, if requested, for susceptibility to measles (IgG, ELISA). Those found to be susceptible were revaccinated. Of 1,228 tested, 264 (21.5%) were susceptible. In the group vaccinated before 1980, 237 of 901 (26.3%) were susceptible, whereas only 27 of 327 (8.3%) vaccinated after 1980 were not immune. Susceptibility was sharply divided by month of age at vaccination at the 14-month mark. Less than 5% of those vaccinated after age 15 months in the 1980s (one of 22, or 4.5%) were susceptible. Waning immunity (secondary vaccine failure) was not found to be a factor in our patients. Despite outbreaks of measles in surrounding communities and in our area, none of our patients developed measles. Identification of high-risk groups and selective measles revaccination should be considered as an alternative to universal revaccination in populations such as ours, since it is more cost-effective and may prove equally successful.