Bellagio brief: vitamin A deficiency and childhood mortality.

A meeting of concerned scientists, health officials, and policy makers was convened in February, 1992, at the Rockefeller Study and Conference Center in Bellagio, Italy, in response to recent calls to control or eliminate Vitamin A deficiency worldwide. The group was commissioned to explore the role of vitamin A status of child health in developing countries, to draw some conclusions, and to consider policy implications to guide program managers and decision makers. Published data were reviewed on the biochemistry and molecular biology of Vitamin by its role in cellular differentiation and immunity; animal models and clinical case reports of vitamin A deficiency; the epidemiology of vitamin A deficiency in human populations and the environment in which it arises; prospective observational field investigations; hospital treatment studies; and controlled, community-based prophylaxis trials. Since vitamin A is essential for normal health and survival as well as normal vision and ocular function, deficiencies increase the rates of childhood mortality and morbidity. Tens of millions of children suffer deficiencies of vitamin A and at least 1 million die to go blind annually as a result. It is also pointed out that increased mortality and morbidity occur at levels of vitamin A deficiency which are lower and less chronic than those required for nightblindness and xerophthalmia. The definition of vitamin A deficiency therefore needs to revised to make it more sensitive to milder degrees of deficiency in the interest of improving public health. Improving vitamin A status in children with deficiencies and treating all measles with vitamin A would greatly reduce child mortality and morbidity, and should be considered a comprehensive component of child survival strategy. The scientific rationale for these conclusions and arguments is provided with references made to available literature.