Vitamin A and Measles
Back in the 1970s, Alfred Sommer, MD, MHS, began working on community interventions in Indonesia where children who were deficient in vitamin A were given a supplement to help stave off vision problems. At the time, the evidence was clear that vitamin A played an important role in vision, especially night vision. Children who were deficient in vitamin A just didn’t see very well in dark settings compared to children who were not deficient. As Dr. Sommer and his colleagues conducted the trial, they also made a very interesting observation.
Dr. Sommer and colleagues observed that children who were being given vitamin A supplements and those who were not deficient seemed to have better outcomes if they became ill with infectious diseases like measles or diarrhea. No, they were not immune to those diseases, but they fared better. Vitamin A deficient children died at a higher rate, it seemed. Something was going on.
To verify what was going on and make sure that it wasn’t some biased observation on their part, Dr. Sommer and colleagues conducted some larger clinical trials in the 1980s and early 1990s. They found that:
“Their work showed that ensuring adequate vitamin A intake can mitigate the effects of common diseases such as measles and diarrhea; reduce child mortality in at-risk populations by 23 to 34 percent to avert up to one million deaths a year; and prevent as many as 400,000 cases of childhood blindness each year.”
As a result, the World Health Organization made vitamin A supplementation for children all around the world a top priority. Further studies showed that a supplement costing just 2 or 3 cents per dose could prevent thousands of dollars in lost productivity by saving the lives of children.
Today, vitamin A deficiency is still a problem, especially in developing nations. And it’s not just vitamin A. Children in developing nations are also deficient in other nutrients, leaving them vulnerable to all sorts of complications. (There is malnutrition here in the United States, though it is more a result of empty calories and inner-city food deserts than structural problems at the national level in the delivery of food and healthcare.) Couple that with a lack of access to immunizations, and you have some very severe outcomes from diseases that we in the United States have long forgotten how deadly they could be.
Let us compare two places in the world where measles is active: Europe and Madagascar. Europe, for the most part, consists of several countries deemed to be industrialized and developed. While there is some variation between countries – and within countries – most Europeans enjoy a high standard of living. They have access to nutritious food and many enjoy the benefits of universal healthcare access. Europeans have also been contending with a resurgence of measles.
In 2018, European countries broke all sorts of recent records when it came to the number of cases of measles. Thirty-four of the 53 member states struggle to bring their immunization level to 95%, the level needed for herd immunity. However, there have been relatively few – if very tragic – deaths in Europe as a result of measles. The death rate from measles has been about the average for industrialized nations: 1 in 1,000.
Compare that epidemic in Europe to the one in Madagascar. According to the World Bank, more than half of Madagascar’s children (5 years of age and younger) are chronically malnourished. The country as a whole is very poor, with over 90% of the population living on less than 2 dollars a day. Combine that with a measles vaccine that costs about 15 dollars per dose, and is rarely available in the most impoverished areas, and you can understand what has happened there recently.
With more than two thirds of children unvaccinated against measles, and the last immunization drive more than 15 years ago, Madagascar is in the middle of one of biggest and worst measles epidemics in the world. With tens of thousands of cases, and almost 1,000 deaths, measles has taken out entire families throughout the country. The estimated mortality rate for measles there is closer to 15 per 1,000 cases, compared to 1 per 1,000 in industrialized nations.
Certainly, malnutrition, lack of access to care and lack of a vaccine have all come together to hurt and kill many children in Madagascar. There is no end in sight to the epidemic there since measles is endemic, meaning that it is constantly occurring with new generations of susceptible children being born each year. Unlike Madagascar, the epidemic in Europe (and the ones we have seen here in the United States) is driven by misinformation and fear of the measles vaccine. Parents are refusing to immunize their children in the developed nations. In the developing countries, like Madagascar, parents are begging for the vaccine to save the lives of their children. Quite a contrast.
Among the misinformation circulating in anti-vaccine circles in the United States is the falsehood that vitamin A somehow protects against measles, or that children who are getting measles in the United States are simply vitamin A deficient. Some anti-vaccine groups have even started crowdfunding efforts to send vitamin A supplements to Washington State, a state with over 520,000,000,000 dollars ($520 billion) of gross domestic product in 2017. (Madagascar’s GDP hovers around $10 billion.)
Needless to say, there is no scientific evidence that vitamin A supplementation prevents measles infection. It’s not even a scientific plausibility. However, vitamin A supplementation as an additional treatment of cases of measles in order to prevent death is recommended by some researchers, particularly in places where malnutrition is known to be a problem. The best prevention of measles continues to be the measles vaccine.
All scientific discoveries come with some level of apprehension, especially if the results are found to be revolutionary, like Dr. Sommer’s observation that vitamin A supplementation prevented deaths from infectious diseases. This is why the scientific method has been developed and refined, helping us confirm these observations and expand on them. As Dr. Sommer and his colleagues found, vitamin A prevents deaths from measles and other infectious diseases, but it does not prevent the infections themselves. For that, we have a vaccine with an excellent track record of safety. Unfortunately, some parents are forgoing all vaccines for their children based on unfounded and non-scientific claims. Other parents in developing nations simply lack the resources and access to the vaccine. As long as structural, societal and communication problems persist, it will not matter how good any vaccine is at preventing an infectious disease: someone, somewhere will be left out of enjoying the benefits of the vaccine, resulting in unnecessary disease and tragic loss of life.
- “The Story of Vitamin A” (https://www.jhsph.edu/news/stories/2003/sommer-vita.html)
- “Vitamin A Deficiency” (https://emedicine.medscape.com/article/126004-overview)
- “Vitamin A Treatment of Measles” (https://pediatrics.aappublications.org/content/91/5/1014)