Antibody response to measles immunization in India.

Antibody response to measles vaccine was measured in 238 subjects aged 6-15 months. Seroconversion rates ranged from 74% at 6 months of age to 100% at 13-15 months; the differences in age-specific rates were not statistically significant. The postimmunization antibody titres increased with increasing age of the vaccinee. Seroconversion rates and antibody titres in 49 subjects with grades I and II malnutrition were not significantly different from those in the 189 normal subjects.These results support the recommendation of 9 months as a satisfactory age for commencement of measles immunization in India. However, the highest antibody levels and seroconversion rates were obtained in children over 12 months of age.