What People Misunderstand This Week: Does Measles Cure Cancer?
The results for 2025 have been tallied, and it’s been a great year for measles. According to the CDC , the number of measles cases in the US has increased from 285 in 2024 to 2,144 in 2025, marking the highest measles incidence rate since 1990. At least 171 cases have already been reported in the first two weeks of 2026 .
As you might guess, experts attribute the rise in measles cases to low vaccination rates . A few months ago, I discussed a number of myths surrounding vaccination and measles in this column , but a new perspective on measles has emerged that seems to be gaining popularity: many people believe that having measles is beneficial for their health.
“There’s a lot of research showing that if you actually have measles, you’re protected later in life. It strengthens your immune system later in life against cancer, atopic diseases, cardiovascular disease, and so on,” Robert F. Kennedy Jr., Secretary of Health and Human Services, said in a recent interview with Fox News . Online, you can find posts like this one, from a chiropractor’s Instagram page , which uses a clip from The Brady Bunch to argue that having measles and other illnesses “prepares a child’s immune system for long-term resistance to chronic problems like cancer and cardiovascular disease.” Others cite news stories like this one from CNN to support claims that measles fights cancer.
Can measles fight cancer?
There’s no evidence that measles can protect against cancer. Period. But the question of whether measles can treat cancer is a bit more complicated. There’s some truth to it, but it’s shrouded in a lot of misconceptions.
The most basic is the meaning of the word “measles.” Oncolytic virus therapy uses genetically modified viruses, including the measles virus, to target cancer cells. A modified version of the measles virus has been successfully used to treat a certain type of cancer and boost the immune response to it. Researchers at the Mayo Clinic report that one patient’s incurable cancer went into remission thanks to this virus. “But this is a completely therapeutic use of viruses, completely different from what happens in natural infections,” said John Bell, a senior scientist at The Ottawa Hospital Research Institute , in an interview . “So it’s not ‘measles cures cancer,’ it’s ‘scientists weaponizing a virus under controlled conditions.'”
Bottom line: the wild measles virus is a dangerous pathogen, not a cure for cancer. Moreover, one of the reasons the viral therapy worked so well for the patient featured on CNN was because she had been vaccinated against measles . Therefore, if a genetically modified measles virus is ever used to treat cancer, it’s better to be vaccinated than not.
Does having measles prevent cardiovascular disease?
One study conducted in Japan found a link between measles and mumps and a reduced risk of death from atherosclerotic heart disease. However, critics point out that this study relied on self-reporting before vaccinations were introduced . Given the virulence of measles, all survey participants likely had measles as children, even if they didn’t remember it, making it difficult to draw any conclusions from this study.
Does having measles help strengthen the immune system?
While a previous illness will likely provide immunity to measles later in life, it harms the immune system overall. A 2019 Harvard Medical School study , published in the journal Science , found that the measles virus can cause “immune amnesia”—the disappearance of up to three-quarters of the antibodies that protect against other infections, such as influenza or the bacteria that cause pneumonia. “The measles virus is like a car accident for your immune system,” Stephen Elledge, a geneticist at Harvard University and senior author of the Science study, told The Los Angeles Times .
“If your child had measles and then developed pneumonia two years later, you wouldn’t necessarily associate the two events. The symptoms of the measles itself may just be the tip of the iceberg,” said the study’s lead author, Dr. Michael Mina.
Meanwhile, we have extremely compelling evidence that the measles vaccine does not cause a general weakening of the immune system—note, for example, the dramatic decline in child mortality from other diseases in places where measles immunization programs were introduced. After measles vaccination was introduced in the United States in the 1960s, mortality from diseases such as pneumonia and diarrhea was halved , and in populations where infectious diseases are more common, the mortality reduction reached 80 percent .
Playing devil’s advocate on the measles issue
Let’s assume the critics are right, for the sake of argument. Even if having measles in childhood reduces the risk of developing cardiovascular disease later in life and strengthens the immune system, it still makes sense to get vaccinated rather than get infected.
Measles is a serious disease. Regardless of any future benefits, measles infection is fatal in three out of every 1,000 cases. About one in every 1,000 children who contract measles develops encephalitis (inflammation of the brain), which can lead to seizures, hearing loss, and mental retardation.
Measles vaccination, on the other hand, is very safe. The most serious side effects result from severe allergic reactions, occurring in approximately one in a million doses . The measles vaccine provides immunity without the risk of encephalitis, without immune amnesia, and without risking the child’s life based on a hypothetical future benefit. If measles infection does in fact beneficially prepare the immune system, vaccination suppresses the immune response, thereby repairing the damage. However sympathetic one may be to the “infection is beneficial” argument, infection is a dangerous and ineffective way to achieve immunity.