The shaky science behind treating measles with vitamin A

Yahoo

21-03-2025

As a fatal measles outbreak continues to spread, the United States' leading public health official has offered some advice that's not backed by science. Secretary of Health and Human Services Robert F. Kennedy Jr., told Fox News earlier this month that his department was delivering vitamin A to Texas, and that health officials were getting results by treating measles with cod liver oil, a substance that has high levels of vitamins A and D.
While vitamin A is, in fact, part of the recommended treatment for measles, 'It's not good advice,' said Adam Ratner, a pediatric infectious disease expert, and member of the American Academy of Pediatrics (AAP) Committee on Infectious Diseases. 'I think the problem is that he's taken something where there's a kernel of truth, which is that there is an interaction between vitamin A status and measles outcome, and he turned that into vitamin A and vitamin D. He's talking about cod liver oil, which is not how you would supplement someone, in part, because there's not a known amount of vitamin A in that.'
Kennedy's advice couldn't have come at a worse time. As of March 18, the Texas Department of Health and Human Services was reporting 279 cases since the end of January, with 36 patients needing hospitalization. One unvaccinated child had died in Texas, while another unvaccinated person died in New Mexico. Cases have been reported in at least seven other states. According to the World Health Organization (WHO), over 100,000 people, mostly children under the age of five, died of measles globally in 2023.
While Kennedy may have been wrong overall, as Ratner noted, there was still a sliver of truth in his statement. Both the CDC and WHO recommend dosing children diagnosed with measles with vitamin A, which is found in foods like carrots, spinach, pumpkins, eggs, milk, sweet potatoes, and mangoes.
Numerous studies have found vitamin A is effective in reducing the severity of measles, including lowering mortality rates. According to AAP guidelines, children who test positive for measles should be given two daily doses of vitamin A for two days, with the dosage varying by age.
However, many of the studies that concluded vitamin A was an effective treatment were conducted on populations that tend to be malnourished in general. In more developed countries, such as the United States, vitamin A's effectiveness is less clear. A 2021 study conducted in Italy found no significant difference between vitamin A and a placebo in treating children admitted to hospital with measles.
Ratner noted that the Italian study suffered from a small sample size, but acknowledged that, 'There's some data on the side of saying that the impact in Italy or somewhere like the United States is likely to be less of giving vitamin A supplementation than it is somewhere with a lot of malnutrition. This goes back to observations from a long time ago that children who were malnourished had much higher rates of severe disease and death from measles than kids who were well nourished.'
[ Related: How to check your measles vaccination status amid outbreak. ]
The reasons that vitamin A is good for measles are both straightforward and complex. The vitamin 'plays a vital role for immune system functioning,' said Erik Blutinger, an assistant professor of Emergency Medicine at the Icahn School of Medicine. 'It helps the body produce antibodies. It helps the body mobilize T cell responses, and it prevents immunity from weakening overall.'
Vitamin A is also critical to skin health, as it helps maintain healthy cells in the epidermis, the outermost layer of skin.
'The skin is one of our vital organs and serves as a protective barrier even for our immune system,' adds Blutinger.
The trouble with the recent recommendation is that some parents may hear that a little vitamin A is good, so more must be better. As with most medicines, this can be dangerous thinking. In large doses, vitamin A can become toxic. Symptoms can include nausea, vomiting, headaches, and blurred vision. In extreme cases, it can even lead to permanent liver, bone, or nervous system damage.
Vitamin A is particularly dangerous 'because it's fat soluble, it gets stored in the liver,' said Ratner. 'It's very easy to give someone too much, and that can either be too much in terms of individual doses or even reasonable doses for too long a period of time. It can endanger the liver, it can endanger the bones. Vitamin A supplementation is great for people who are vitamin A deficient, and it's a reasonable thing to do just for the two doses at the time of measles diagnosis, because we think that there's a potential benefit just during that little window. But it's not something that people should be doing on their own, and it's not something that should be done long term unless there's some very specific medical condition that someone's treating.'
In a 2023 article published in the Journal of the American College of Emergency Physicians Open, Blutinger noted that there is no antiviral treatment for measles yet available. While two days of vitamin A doses is recommended, followed by another dose several weeks later, the study concluded that the best and surest way to combat the disease remains vaccination.
[ Related: Is raw milk safe? Science has a clear answer. ]
Beyond vaccinating, the best advice Blutinger could offer parents was to 'be well informed with verifiable information that comes from your primary care doctor and from the medical professionals that do not care about politics.'
'My other advice is to take measles extremely seriously and to do what you can to protect your loved ones, your children, the elderly, everyone around you, because, as we saw during COVID, pandemics are not easily tamed,' he added. 'If measles continues to spread rapidly, we may be in even more serious trouble.'