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Rx for Survival — A Global Health Challenge

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Global Health Champions

Alfred Sommer

Alfred Sommer, MD, MHS

Dean Emeritus and Professor
Johns Hopkins Bloomberg School of Public Health

Alfred Sommer is surely the only eye doctor in the world who can truly claim to have saved millions of lives at a time. His pioneering work in studying vitamin A deficiency and blindness prevention has won him worldwide fame as well as the prestigious Lasker Prize, and saved the vision of children throughout the developing world.

In the early 1970s, Sommer, an ophthalmologist by training, was working in some of the poorest countries on Earth for the Epidemic Intelligence Service of the Centers for Disease Control. There he began to focus his work on a devastating, startlingly prevalent eye condition called nightblindness.

"A child who is night-blind in a village in India or Bangladesh or Nepal literally can't fend for him- or herself," Sommer explains. "While other kids are walking around the village or playing with toys, these children huddle in a corner."

Sommer saw firsthand the tragic consequences of leaving the condition untreated. "The children will go truly blind, because what happens is the cornea, that clear front of the eye, just melts away. And it can melt away in the course of one day." Millions of children were losing their vision permanently, Sommer learned, because of a simple lack of vitamin A in their diet.

Discovered in 1913 by nutritionist EV McCollum, vitamin A was one of the first essential "micronutrients" to be identified. One of its functions is to produce a light-sensitive chemical called rhodopsin in the retina, which allows us to see in low light. This is why carrots help us see in the dark, along with liver and dark green leafy vegetables like spinach — all foods that were missing from the diets of the children Sommer encountered.

Sommer was in a unique position to combine his expertise in ophthalmology with his training in epidemiology. "Epidemiology is medical detective work," he says. "It's solving who is the perpetrator of a crime. It asks three questions about a disease or an epidemic: when, where, and who?"

In the mid-1970s, Sommer went to Indonesia, where nightblindness was common, to seek answers to these questions and prevent more children from losing their sight. He and his team closely monitored 4,000 children to see which ones became night-blind.

He made a remarkable discovery when reviewing the data: The night-blind children seemed to be dying at a much higher rate than the children with normal sight. Could the vitamin A deficiency that was causing nightblindness also be making the children fatally susceptible to mild childhood illnesses like measles and diarrhea?

There was only one way to find out. Sommer and his team gave an oral dose of vitamin A to 10,000 children and compared them with children not getting vitamin A. The results were astounding: Just two cents' worth of vitamin A given twice a year reduced childhood mortality by a third. "We were absolutely elated," he recalls. "Suddenly you have a very inexpensive, practical way to save more than a million lives a year of young children, year in and year out, and prevent half a million children from going blind."

But critics dismissed Sommer's results as too good to be true, and he couldn't convince them that such a simple solution could save so many lives. "What was most frustrating of all was when you present the hard data and people just say they don't believe it. I mean, how do you deal with that?"

Determined to prove his case, Sommer and his team embarked on their biggest trial yet: Thirty thousand children would be involved, this time in Nepal.

The Nepalese results proved that Sommer had been right all along: Vitamin A could save children's lives as well as their sight. And the lifesaving power of vitamin A did not stop there. In another trial in Nepal, Sommer and his team found that giving pregnant women vitamin A supplements reduced maternal mortality by nearly 40 percent.

The World Bank has judged the vitamin A capsule one of the most cost-effective medical interventions of all time, and programs to dose children with it have now been rolled out in 70 countries.

Sommer is an eminent professor at the Johns Hopkins School of Medicine and the Johns Hopkins Bloomberg School of Public Health, where he has spent most of his career teaching. He and the school's major donor, Mayor Michael Bloomberg of New York, were having dinner one night, discussing the goals of public health. Together, they came up with the school's motto: "Protecting Health, Saving Lives — Millions at a Time." It's also an apt description of Sommer's work and his commitment to public health.

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