Zinc supplementation for prevention of acute respiratory infections in infants: a randomized controlled trial.

Abstract

To study the effect of 2 weeks of prophylactic zinc supplementation on incidence and duration of acute respiratory infections. Randomized double blind controlled trial. Community based; urban resettlement area in North-East Delhi, India. 272 children aged 6-11 months with acute respiratory infections. Children receiving zinc supplement within the past 3 months, severely malnourished, immuno-deficient, on steroid therapy, with severe illness requiring hospitalization, or children of families likely to migrate from the study area were excluded. Placebo (syrup base) or zinc (20 mg/5 mL elemental zinc as zinc sulfate) orally given for a period of 2 weeks. Incidence, type and duration of acute respiratory infections, and adverse effects. No effect on incidence of acute respiratory infections was noted. A decrease of 15% (0.78-0.94) in days and 12% (0.78-0.94) in duration of episode in acute respiratory infections was observed. Incidence of acute lower respiratory infections decreased by 62% (0.26-0.36) and the effect remained for full five months of follow up. There were no drop outs due to side effects. Prophylactic zinc supplementation for two weeks may reduce the morbidity due to acute lower respiratory infections but not overall rate of acute respiratory infections in infants aged 6-11 months in similar populations.