Nutritional Status and Measles Antibody Titer in Children Living in Urban Slums of Mumbai

Abstract

Abstract Objectives To determine a) the prevalence of protective measles IgG titers in young children living in urban slums of Mumbai, and b) the association of nutritional status assessed through a combination of anthropometry and micronutrient biomarker concentrations with these titers at baseline and after 9 months of follow-up. Methods Anthropometry and serum concentrations of vitamins A, B12, D; ferritin, and zinc, and anti-measles immunoglobulin G (IgG) were measured among 12–24-month-old children in urban slums of Mumbai. Demographic data and health history were also collected. The association between baseline predictors and measles titers was assessed using linear regression for continuous measles titer and change in measles titer, and binomial regression for the dichotomous outcome of having a protective titer at baseline and at endpoint (>16.5 AU/mL). Results At baseline (n = 122, median age 14.5 months), 71% of children reported receiving dose 1 of the measles vaccine typically administered at 9 months of age, while 57% of children had protective measles IgG titers (>16.5 AU/mL). After 9 months of follow-up, 73% of children had protective titers. Multivariate models found measles IgG titer at baseline was inversely associated with vitamin D deficiency (<50 nmol/L) and vitamin B12 deficiency (< 148 pmol/L), and positively associated with child's age, maternal height, and birth weight. Iron deficiency (serum ferritin <15 ng/ml) at baseline was associated with lower measles IgG titers at endpoint (median age, 23.9 months). Conclusions The prevalence of protective antibody titer against measles virus in this pediatric urban slum population was less than anticipated, and age, maternal height, and birth weight were positively associated with increasing measles IgG titers. Deficiency in vitamins A, B12, and D, as well as iron, were associated with lower measles IgG titers, highlighting the potential role of micronutrient status in vaccine response. Funding Sources HarvestPlus.