Randomised Trial of Vitamin A Supplementation Given With Routine Childhood Vaccines at National Immunisation Days

Vitamin A supplementation (VAS) acts as an adjuvant to vaccines, and VAS has been shown to enhance both cellular and humoral immune responses in animals and in humans. Routine childhood vaccinations have recently been shown to have important non-targeted effects on mortality, i.e. effects that cannot be explained merely by the prevention of the targeted disease. We have hypothesized that the improved survival after VAS may depend not only on the prevention of vitamin A deficiency, but also on vitamin A amplifying the non-specific immune modulation induced by routine vaccinations.

In the present study we used information collected in connection with a national vitamin A campaign in Guinea-Bissau during which different doses of VAS was provided together with missing doses of DTP, OPV, and measles vaccines. We aimed to study the potential interactions between VAS and vaccine type.