In this issue of Ophthalmic Epidemiology, colleagues from India and Pakistan, two countries comprising the densely populated and largely impoverished sub-continent, independently document the continuing tragedy of vitamin A deficiency and its impact on sight and life.
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 can alter these difficult measurements). But all too often governments do not really take this obligation seriously, and even when they do, huge disparities in coverage exist. The poorest children, who are in greatest need, tend to be neglected and suffer the most.
The carefully conducted population based survey in Pune's urban slums documents the continuing high rates of xerophthalmia, exceeding the WHO's criteria for “a public health problem,” despite the long-standing presence of a governmental vitamin A distribution program. Shockingly, fewer than 20 percent of eligible children reportedly received a vitamin A supplement. Numerous reports, many unpublished, document the continuing persistence of high rates of xerophthalmia, and therefore unnecessary vitamin A deficiency, and childhood mortality and blindness, from many areas of this vast and heavily populated nation.
Pakistan was long claimed an absence of significant vitamin A deficiency, despite its poverty, its relative lack of health services, and one of the highest rates of infant and under-five mortality in the world, particularly in rural, and especially, tribal areas. Indeed, the lead author first became aware of the existence of xerophthalmia during a study tour in India. Upon returning to Pakistan he immediately encountered vitamin A-responsive cases of corneal ulceration; a manifestation of severe deficiency among children generally ill with advanced malnutrition, pneumonia and other infections. To document its extent, and alert other medical authorities to its presence, the Pakistani investigators “merely” established an active reporting system among the far-flung ophthalmic practitioners in one underserved area. The number of case encountered readily documents the existence of significant deficiency, which calls for immediate, urgent action. Surveillance systems of this sort notoriously underestimate the real extent of the problem. As the authors note, keratomalacia is associated with very high mortality; in one study, it was estimated that children not treated in hospitals suffered a case—fatality rate of over 90 percent. Since few will make it to an appropriate hospital for care, fewer still will survive long enough to be encountered, alive with healed corneal scars.
These two papers represent a wake-up call to health officials in both Pakistan and India. Control of vitamin A deficiency is an urgent matter. Government complacency blinds and kills.