A's Long and Winding Road
Date: February 1, 2013
The history of medicine contains few examples of the swift discovery of an illness’s cause or the means for curing it. Indeed, many individuals today—assured regularly of the miracles of modern medicine—undoubtedly are frustrated by the seemingly endless effort to find definitive cures for cancer, HIV/AIDS, or ALS.
Those who are discouraged by such lengthy probes might be reassured to learn that it took nearly 200 years of scientific inquiries and experiments to pinpoint the critical role that vitamin A deficiency plays in the development of childhood blindness, susceptibility to potentially fatal illnesses, and even death.
Amazingly, as Richard D. Semba points out in The Vitamin A Story: Lifting the Shadow of Death (Karger 2012), even 20 years ago it was not possible to define vitamin A deficiency as a nutritionally acquired immune deficiency syndrome. Only research conducted over the past two decades has enabled physicians to assert unequivocally that providing sufficient vitamin A can prevent or cure a wide variety of afflictions—such as ensuring that a case of childhood measles doesn’t become deadly or protecting a young mother from puerperal sepsis (childbed fever).
Despite these advances in vitamin A knowledge (and the demonstrable success of campaigns to eradicate vitamin A deficiency, especially in the developing world), many such efforts have been blocked by what he calls “insurmountable obstacles—politics, cultural conflicts, bogus science, and commercial agendas.”
All of the impediments are manmade, and the “victims who continue to suffer under the shadow are mainly the children,” writes Semba, the inaugural W. Richard Green Professor of Ophthalmology at Hopkins’ Wilmer Eye Institute. He also holds joint appointments in the Department of Molecular Microbiology and Immunology and the Department of International Health at the Bloomberg School of Public Health.
An excellent writer, Semba has produced a succinct history suitable for professionals and the general public alike. It clearly and effectively details how the vitamin A story is emblematic of the long, bumpy road to scientific discovery and public health improvement, made perilous by academic, ideological, and sociological potholes.
Semba’s chronicle contains everything from the links between vitamin A deficiency and night blindness among 19th-century sailors, to childhood mortality rates in the France of Napoleon III, to early 20th-century efforts to determine what “accessory factors” in various foods led to health improvements.
“The characterization of vitamin A, from the hints of its existence shown by [French physiologist François] Magendie in 1816 to its isolation, description of chemical structure and eventual synthesis in 1947, was an excursion down a tortuous road that took nearly 130 years to complete,” he notes.
Hopkins scientists played a significant role, but as Semba candidly observes, some did not exactly cover themselves with glory.
For example, he writes that although Hopkins biochemist Elmer V. McCollum (1879-1967) did indeed report important discoveries in 1918 on the impact of what he called “fat-soluble A and water-soluble B” deficiencies on the development of blindness in laboratory rats, McCollum’s later claim to have “discovered” vitamin A was “an exaggeration,” embellished by the “distorting mirror of hindsight.”
Just before leaving the University of Wisconsin to come to Hopkins, he purposefully sabotaged the research of a one-time colleague by releasing from their cages all of the rats on which the now-rival scientist had been experimenting.
A far more admirable Hopkins physician and researcher is Semba’s mentor, the Lasker Award-winning ophthalmologist and former public health school dean Alfred Sommer. His pioneering 1980s studies involving tens of thousands of Third World children convincingly demonstrated that vitamin A supplements could reduce childhood mortality by 30 percent by guarding against diarrhea, measles, blindness, and other illnesses.
Sommer and his teams had to overcome enormous obstacles to achieve that landmark accomplishment. Yet political opposition—plus obtuseness or obstinacy in some scientific quarters—still imperils progress, Semba writes. Some “ten million children are still dying each year in developing countries, mostly of preventable causes….In other words, the fight goes on. There have been many successes, but not enough.” —Neil A. Grauer