Measles Outbreak 2025

Molly Cavanaugh

The United States is undergoing a measles outbreak that has infected over 1000 people in 33 different US states (1). Measles is a very contagious and potentially deadly single-stranded RNA virus. Around 90% previously uninfected or unvaccinated people will develop measles when exposed (2). Clinical symptoms of the virus include a tell-tale large flat and small, raised red rash, fever, a dry cough, runny nose, and red, watering eyes. In addition to being uncomfortable and highly contagious, it is deadly for 1 to 3 people out of every 1000 cases, with most deaths being children under 5 (3).

Measles rash on children

In 2023, an estimated 107,500 people died of measles across the world (4). Measles remains a leading cause of childhood deaths. The MMR vaccine (measles, mumps, and rubella) is a two-dose vaccine recommended for children at 12-15 months and then again at 4-6 years. After two doses, the vaccine is 97% effective against measles, 86% effective against mumps, and 97% effective against rubella. Side effects of the vaccine are typically mild and are not linked to autism (5). Measles vaccination prevented more than 60 million deaths between the years of 2000 and 2023. The last measles death before 2025 in the US nearly 5 years ago, but since the start of this outbreak 3 people in the US have already died (6). Of the 1195 known cases, 95% of patients have been unvaccinated and 29% have been under 5 years old. None of these people needed to suffer from this preventable virus.

Why has this outbreak been so much larger than past years? This is largely due to governmental reasons. Robert F. Kennedy Jr, Health and Human Services Secretary, has been influential during this most recent measles outbreak. Although there is a safe and effective vaccine, he has promoted alternative treatments such as vitamin A and cod liver (7). This is not the first time RFK has played a role in an outbreak. His foundation, Children’s Health Defense, in Samoa was responsible for vaccine misinformation which contributed to a measles outbreak in 2019 where 83 people died (8). In addition to vaccine misinformation, the government has contributed to the outbreak by removing protections against measles outbreaks (9). Misinformation and cuts in government spending will impact the outlook of the measles outbreak in a disastrous way. We must press our government to speak up to advise the measles vaccine and save lives.

There are real, medical reasons why the people in the US should not use alternative treatments for measles. For example, vitamin A has value in treating severe measles cases but should only be done under the supervision of a doctor. This is partly because vitamin A that is bought online or at a normal store can be easily overused. In March of 2025, Texas treated multiple cases of children with measles developing vitamin A toxicity that resulted in impaired liver function (10). There have been no details reported at this point as to how the patients developed vitamin A toxicity. However, one can speculate based on what types of vitamin A are easy to buy and maximum strength. One can buy a 10,000 IU  (international units, they are used as a dose in biology ranging from vitamins to vaccines) vial of vitamin A in only 1 fluid oz, 30 mL (11). If someone were to drink one a day, they would develop vitamin toxicity over time. Now let’s imagine that your child is dying and the Secretary of Health and Human Services tells you that this vitamin might just work! Would you give your child one a day, one an hour? This is a position you are supposed to be able to trust, which is why RFK is so dangerous. 

So where did this idea come from? This is a misunderstanding based on a medical study (11). This study concludes that treating with vitamin A reduces deaths due to measles. This is true, for the participants studied. Unfortunately, this is based on the participants being vitamin A deficit. Less than 1% of the US can be considered vitamin A deficient (12). This means that while vitamin A is incredibly important to measles infections, almost all Americans do not have vitamin A issues that will not experience relief from this treatment because their vitamin A levels are at a normal level. This is an alternative measure that can make desperate parents overdose and poison their children, all in the name of relief. I hope that scientists and patients who investigate vitamin A will look at more representative medical studies.

Perhaps the saddest part of the story is that measles does not need to kill another child. Some viruses, such as Nipah virus and influenza,  cannot be easily eradicated because they live in animals or do not have an effective and affordable prevention/treatment available (13) . Measles could be eradicated through a comprehensive health campaign. Public health must be a global commitment, but it must be recognized. Recently, a baby died of measles in Ontario when the virus transferred from the mother who was unvaccinated (14). This outbreak will not end until we decide to end it through our actions. There are people who cannot be vaccinated due to allergies. It is the duty of the rest of us to protect the few who cannot protect themselves. This baby could not be vaccinated. This newborn baby died. A whole life wiped out before they could even live. The mother of the baby was unvaccinated and spread measles to their child. This is a tragedy. Perhaps the mother avoided the vaccine due to misinformation, but it is also possible that the mother had an allergy and could not be vaccinated. We all must view public health through a global lens. There will always be people who medically cannot take the vaccine, or people who are far abroad and out of the reach of most vaccines. Measles can be ended, totally and completely. I have been vaccinated, have you?