Measles, a disease once thought to be a thing of the past, is making a comeback in the United States and around the world. The Centers for Disease Control & Prevention reported 2,255 confirmed cases of measles in the U.S. in 2025, with an additional 416 cases reported in the first twenty-three days of January alone. A South Carolina outbreak has reached 789 cases as of January 27, 2026.
As an emergency room doctor, I want to highlight five important things that families need to know about measles:
1. The Measles Is More Than Just a Rash
Measles is a highly contagious viral infection that affects the entire body. Symptoms typically appear 7-14 days after exposure and include a high fever, cough, runny nose, and red, watery eyes. One early sign of measles is the presence of Koplik spots, tiny white dots that appear inside the mouth. The rash, a hallmark of measles, usually appears 3-5 days after the initial symptoms and starts on the face before spreading downwards. Measles is incredibly contagious, with infected individuals able to spread the virus before they even know they are sick.
2. Measles Outbreaks Are Spiking Due to Declining Vaccination Rates
Measles outbreaks are on the rise due to decreasing vaccination rates. In the U.S., MMR vaccination rates dropped from 95.2% in 2019-2020 to 92.5% in 2024-2025, leaving 280,000 kindergartners unprotected. Even a small drop in vaccination coverage can lead to localized outbreaks. Globally, vaccination rates remain low, with the WHO European Region reporting the highest number of measles cases in 25 years in 2024.
3. Certain Groups Are More Vulnerable to Severe Complications
Individuals in certain high-risk groups, such as infants, young children, pregnant women, and immunocompromised individuals, are more likely to experience severe complications from measles, including pneumonia, encephalitis, and even death. Measles-induced immune amnesia can also suppress the immune system, increasing the risk of secondary infections.
4. What to Do If You Suspect Measles
If you suspect you or a family member has measles, it is crucial to call ahead before seeking medical attention to prevent further exposure. Isolate yourself at home and follow instructions from healthcare providers. Post-exposure prophylaxis may be recommended for those who have been recently exposed to the virus.
5. Your Best Protection Against Measles: Vaccination
Vaccination is the most effective way to protect against measles. The MMR vaccine is highly effective, with two doses being over 99% effective at preventing the disease. It is important for both children and adults to ensure they are up to date on their vaccinations to prevent the spread of measles.
In conclusion, measles is a serious and highly contagious disease that can have severe consequences, especially for vulnerable populations. Vaccination is key to preventing outbreaks and protecting the community as a whole. Stay informed, stay vaccinated, and help stop the spread of measles.
