Objective: To determine the pattern of decline of maternal antibodies in 0-9 month old infants and to study the prevalence of measle antibodies and their levels in 9 month to 5 year old children, regardless of their immunization status.
Methods: A cross-sectional study covering 456 children in the 0-5 year age group residing in 9 registered villages in a rural area of Aligarh District was conducted. The study included the interview of parents, clinical examination of children, and Hemagglutination Inhibition Test for Measles Antibody Titre.
Results: There was rapid decline in seropositivity from 100% in the 0-3 month age group to 18% in the 6-9 month age group. There was a positive correlation (r = 0.77) between decline of seropositivity and age. Measle immunization coverage rate was 64.5%. In 202 children where immunization was confirmed by availability of card, sero-conversion was 96.5%. Of the 118 unvaccinated children, 9% were sero-positive. Of the 71 children who had a history of measles infection, 75% were seropositive indicating correct identification of measle infection by the parents.