Evaluating association of vaccine response to low serum zinc and vitamin D levels in children of a birth cohort study in Dhaka

BACKGROUND: Vaccine-preventable infectious diseases are often responsible for childhood morbidity and high rates of mortality. Immune response to the vaccine is associated with multiple factors in early childhood and measured by antibody titers. Among them, micronutrient deficiencies such as vitamin D and zinc deficiencies are the most important in resource-limited settings like Bangladesh. OBJECTIVE: We aimed to evaluate the association of vaccine response to low serum zinc and vitamin D levels in children. METHODS: We evaluated vaccine response for measles and poliovirus, tetanus and pertussis toxoid, and Ig A antibody levels to rotavirus by ELISA and serum vitamin D and zinc at 7 and 15 months in the MAL-ED birth cohort of the Bangladesh site. By using population-specific generalized estimating equations (GEE), the association between each explanatory variable and the binary outcome variable was examined longitudinally where the dependent variable was vaccine titers and the independent variables were low serum vitamin D and zinc levels. RESULTS: The GEE multivariable model identified a positive association between serum zinc level and tetanus vaccine titer (OR: 1.84; 95% CI: 1.07–3.17 and p value = 0.028) after adjusting for age, gender, birth weight, WAMI score, diarrhea, ALRI, exclusive breastfeeding, serum ferritin, serum retinol and undernutrition (stunting, wasting, underweight). No association was found between the rest of the vaccine titers with serum vitamin D and zinc level (p > 0.05). CONCLUSION: In the MAL-ED birth cohort, where children were followed for five years, serum zinc level had a positive impact on tetanus vaccine titers.