RESUMEN
Cases of measles among 165 vaccinated and unvaccinated children were studied and the level of measles antibody in 230 previously vaccinated children was determined. Associations between demographic factors and immunological response to vaccination were also investigated. Approximately 80% of the children with measles had been vaccinated; their cases had significantly lower rates of complication. Rural areas accounted for significantly higher numbers of unvaccinated cases. Vaccination status did not correspond to place of exposure, duration of prodrome or accuracy of preliminary diagnosis. The seropositivity rate among vaccinated children was 86.1% with no significant variation with age. We recommend a second dose of measles vaccine and maintaining high vaccine coverage