Defense against infectious disease is a matter of the highest
importance for the health and development of tropical populations.
Since the observation that mortality in children is
higher in children with vitamin A deficiency [24,25], there has
been great interest in determining whether micronutrients
interact with immune responses and other aspects of host
defense. Although there was no placebo group in this study, it is
possible that vitamin A alone was sufficient to decrease diarrhea
and respiratory morbidities [26–29].