When Missing Data Revealed a Hidden Killer
Diagnosing measles doesn't just involve looking at a rash.
Dr. Al Sommer did his Epidemic Intelligence Service training with the Centers for Disease Control and Prevention in Bangladesh. A few years later, he was doing research in Indonesia on how vitamin A affects vision in children. This was in the early 1970s, before anyone had any idea that vitamin A might do anything more than help with night blindness. (After all, the idea that carrots help you see at night comes from the fact that carrots are high in vitamin A, and vitamin A does help with eyesight.)
Dr. Sommer was looking at one of those old-fashioned computer printouts from a dot matrix printer—pages folded and perforated, stacked in sheaves. The data showed follow-up eye tests from kids with various levels of vitamin A. But Al noticed something odd: The kids with the lowest vitamin A levels also had the lowest follow-up rates.
Many researchers would’ve just noted the incomplete follow-up and moved on. But as with many great discoveries, it all started with curiosity.
Al asked: Why? Why aren't these kids coming back?
So, with his research team, he went out and found out.
It turned out the reason the kids with the lowest vitamin A levels weren't coming back was a terrible tragedy – they were dead.
This tragedy became apparent because of a brilliant observation—seeing the invisible, recognizing that a data anomaly was actually the footprint of a lethal deficiency. This led to a groundbreaking discovery. It took many more years of careful studies, but eventually, it was proven that giving vitamin A to children in lower-income countries who are at high risk—at precise doses and schedules—could dramatically reduce childhood mortality. Large trials in Indonesia, Nepal, and elsewhere showed reductions in all-cause child deaths by as much as a quarter.
Vitamin A supplementation has since saved millions of lives globally, especially in places where deficiency is widespread. Sommer's work earned him the Lasker Award in 1997.
When I was an EIS (Epidemic Intelligence Service) officer twenty years later, in 1990, there was a large measles outbreak in New York City. My supervisor, Dr. Kelly Henning—wise then and wise now—encouraged me as I brainstormed ideas for studies along with measures to control the outbreak. She recommended that I follow up on one idea: measure vitamin A levels in acute and convalescent serum of children with measles.
Diagnosing measles doesn't just involve looking at a rash. It involves lab confirmation—typically with two blood samples, one taken while the child is acutely ill and another about two weeks later. That's called acute and convalescent serum.
We used these samples to track vitamin A levels in children with measles, sending the samples, carefully preserved, to the fantastic environmental health laboratory at the CDC in Atlanta. The findings were remarkable.
Children had low vitamin A level when they were acutely ill. And these levels rebounded two weeks later—without administration of any vitamin A. That's because vitamin A is an acute phase reactant—it drops during inflammation and fever. By that time, studies had shown that giving vitamin A to children with measles in lower-income countries could lead to better outcomes: faster resolution of fever, lower risk of pneumonia, even reduced mortality. It's not a cure, but it helps. But only if it’s given correctly.
Vitamin A is a fat-soluble vitamin. That means your body stores it, and if you take too much, you can get very sick—seizures, swelling of the brain, and other serious problems.
So when RFK Jr. reports that vitamin A and other treatments are resulting in “almost miraculous and instantaneous recovery?”
That's dangerous bullshit. (For more about why I use the term bullshit, please read the inaugural essay of this Substack and have a careful look at the tie given to me by a widower.)
The truth is both more limited and more remarkable. Vitamin A supplementation can reduce measles mortality in deficient children when given at proper doses (two carefully controlled doses depending on the child’s weight and age, given 24 hours apart). But it's not a cure. It doesn't prevent measles. And very few children in the U.S. are deficient in vitamin A—probably less than 1%. Fortification of milk and other foods (another invisible public health success story!) keeps deficiency here very low.
The real story of vitamin A is better than the fantasy version. Because it's real. Because it's science. Because it started with careful observation, was tested with rigorous studies, and has been implemented to save the lives of more than ten million children.
That's The Formula: See the invisible. Believe that change is possible. Create solutions that work.
In an era when supplement hucksters and political appointees push simple "cures," understanding the facts matters more than ever. Sommer's discovery wasn't about finding a miracle—it was about careful observation revealing a specific intervention that works in specific circumstances.
It’s not as sexy as a miracle cure, but unlike miracle cures, it works.
In this Substack, I’ll share more about how to use The Formula to save lives and how to use it to maximize your chances of living a long and healthy life able to do the things you want to do.
Next week: a vitamin that might actually make sense to take.
Tom
Dr. Tom Frieden is author of The Formula for Better Health: How to Save Millions of Lives – Including Your Own.
The book draws on Frieden's four decades leading life-saving programs in the U.S. and globally. Frieden led New York City's control of multidrug-resistant tuberculosis, supported India's efforts that prevented more than 3 million tuberculosis deaths, and led efforts that reduced smoking in NYC.
As Director of the CDC (2009-2017), he led the agency's response that ended the Ebola epidemic. Dr. Frieden is President and CEO of Resolve to Save Lives, partnering locally and globally to find and scale solutions to the world's deadliest health threats.
Named one of TIME's 100 Most Influential People, he has published more than 300 scientific articles on improving health. His experience is, for the first time, translated into practical approaches for community and personal health in The Formula for Better Health.