As both papers note, vitamin A deficiency is a major cause of death and blindness among young children throughout the developing world. UNICEF and the World Health organization have, since the early 1990s, called for global control of the problem, most recently as a major means of achieving the Millennium Development Goals. The World Bank has long noted that vitamin A deficiency control programs, primarily through administration of a single large dose of vitamin A twice a year to children 6 months through 5 years of age, is one of the most cost-effective health interventions in existence. More recently, the Copenhagen Consensus, an annual assessment by leading economists on the best means by which to deploy $50 billion dollars to boost development and alleviate poverty, have placed the prevention of vitamin A and other micronutrient deficiencies at the top of their list.

UNICEF, the lead implementing agency, not only supplies over 500 million doses of vitamin A for distribution each year, largely provided with funds from the Canadian Government, but includes official government statistics on coverage rates as one of the key health metrics in their annual “State of the World’s Children” report. Many countries report coverage rates of over 70 percent. While generally hard to believe, some, in fact, achieve them. Carefully conducted repeat prevalence surveys in Indonesia, Bangladesh, Nepal and elsewhere have shown as much as a 95 percent decline in xerophthalmia rates, with presumably, a comparable impact on under-5 mortality (something more difficult to ascertain as variations in climate, famine and infections