No strong long-term effect of vitamin A supplementation in infancy on CD4 and CD8 T-cell subsets. A community study from Guinea-Bissau, West Africa

The World Health Organization recommends that 100,000 IU of vitamin A be gi ven to infants between 6 and 12 months of age at the same time as measles v accination in order to prevent vitamin A deficiency. In the present study, our aim was to assess the effect of vitamin A supplementation on T-cell sub sets in a randomized factorial design, seeking a possible modifying effect of measles vaccination. Three hundred children were allocated either to two doses of measles vaccine at 6 and 9 months of age or to poliomyelitis vacc ine at age 6 months and measles vaccine at age 9 months. Within each group, infants were to receive two doses of vitamin A or two doses of placebo at 6 and 9 months of age. We found no significant effect of vitamin A suppleme ntation on CD4 and CD8 T-cell subsets at 3 and 9 months after supplementati on. We found no effect of measles vaccine and no interaction between vitami n A supplementation and measles vaccine. Based on these observations, vitam in A supplementation does not seem to have a strong long-term effect on CD4 and CD8 T-cell subsets in infants without clinical vitamin A deficiency.