Doctors treating people hospitalized as part of a measles outbreak in Texas and New Mexico have also found themselves facing another problem: vitamin A toxicity.
At Covenant Children’s Hospital in Lubbock, near the outbreak’s epicenter, several patients have been found to have abnormal liver function on routine lab tests, a probable sign that they’ve taken too much of the vitamin, according to Dr. Lara Johnson, pediatric hospitalist and chief medical officer for Covenant Health-Lubbock Service Area.
The hospitalized children with the toxicity were all unvaccinated.
US Health and Human Services Secretary Robert F. Kennedy has centered his response to the outbreak on vitamin A, even suggesting in a Fox News interview that it could work “as a prophylaxis.”
But overuse of vitamin A can have serious health consequences, and there is no evidence that it can prevent measles.
The only way to prevent infection with the measles virus is through the measles-mumps-rubella (MMR) vaccine, which is 97% effective against measles after two doses. Kennedy has said that he does “encourage” vaccination but that it is a “personal choice.”
“If people have the mistaken impression that you have an either-or choice of MMR vaccine or vitamin A, you’re going to get a lot of kids unnecessarily infected with measles. That’s a problem, especially during an epidemic,” said Dr. Peter Hotez, co-director of the Texas Children’s Hospital Center for Vaccine Development and dean of the National School of Tropical Medicine at the Baylor College of Medicine. “And second, you have this unregulated medicine in terms of doses being given and potential toxicities.”
In specific doses taken under the care of a physician, vitamin A can play a role in treatment for measles. That’s why the World Health Organization and US Centers for Disease Control and Prevention recommend it in serious cases. But the patients who were reported to have toxicity were probably not taking the vitamin under the supervision of a physician, Johnson said.
Vitamin A is most useful for measles support in people who have a specific deficiency, and studies suggesting its use mainly draw on evidence from low-income countries where that deficiency is common. The patients in West Texas are generally well-nourished, said Dr. Lesley Motheral, a pediatrician in Lubbock, so experts say it’s unclear how beneficial the vitamin might be in this setting.
Vitamin A has an important role in immunity and vision. It’s fat-soluble, so when someone takes too much, it can accumulate in organs like the liver. Excess vitamin A can cause dry skin and eyes, blurry vision, bone thinning, skin irritation, liver damage and other serious issues. In pregnant women, excess vitamin A can lead to birth defects.
Patients with toxicity can receive supportive care like fluids for low blood pressure or moisturizers for dry skin and eyes, Motheral said. But more serious damage will need to be evaluated and given further management.
“Recovery for patients with acute toxicity can be rapid when the vitamin is discontinued,” she said. “Chronic toxicity can affect bones, brain and of course the liver. … Sadly, some of the more serious problems with vitamin A toxicity are not always reversible.”
The Council for Responsible Nutrition, a trade association for dietary supplement and functional food manufacturers, issued a statement Wednesday warning parents against using high doses of vitamin A to try to keep their children from getting measles.
“While vitamin A plays an important role in supporting overall immune function, research hasn’t established its effectiveness in preventing measles infection. CRN is concerned about reports of high-dose vitamin A being used inappropriately, especially in children,” the statement says.
Johnson said she has seen people who were taking vitamin A for measles treatment as well as for prevention. She doesn’t know exactly where these patients heard that they should be taking a lot of vitamin A, she said, but the approach is heavily discussed on social media.
“It’s coming out of the health and wellness … influencer industry that downplays the importance of vaccines and tries to promote various spectacular cures like ivermectin or hydroxychloroquine or vitamin A,” Hotez said.
Ivermectin, a deworming medication, and hydroxychloroquine, an anti-malarial drug, were both incorrectly touted as treatments for the Covid-19 pandemic but resulted in many poison control reports and an estimated $200 million in unnecessary spending. Experts worry that the drug misinformation so rampant during Covid could mirror rhetoric about vitamin A for measles prevention.
In his Fox News interview, Kennedy endorsed an unconventional treatment regimen for measles including a steroid, an antibiotic and cod liver oil, which is rich in vitamin A. He praised two West Texas doctors who he said were using this remedy on their patients and had seen “almost miraculous and instantaneous recovery.”
The antibiotic, clarithromycin, could be an attempt to prevent secondary bacterial infections like pneumonia, but evidence for that is limited. Budesonide is a steroid with a variety of uses, but it’s not clear whether or how it might help someone with measles.
The measles outbreak has now affected at least 379 people across Texas, New Mexico and Oklahoma. Kansas has reported 23 measles cases, and officials said Wednesday that they may also be linked to the outbreak.
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