Measles
Measles, a highly contagious respiratory disease once considered eliminated in the United States, has made a concerning return. As of March 2026, more than 2,300 confirmed cases have been reported across 45 states, with the vast majority linked to outbreaks. This resurgence highlights how quickly measles can spread when vaccination rates decline and reinforce the importance of maintaining strong immunization coverage to protect communities.
Measles infects the respiratory tract and then spreads throughout the body. Symptoms typically appear around 10 to 14 days after exposure; these typically include:
- Fever
- Dry cough
- Runny nose
- Sore throat
- Inflamed eyes
- Ear infection
- Tiny white spots with light centers on a red background found inside the mouth on the inner lining of the cheek, and/or
- A skin rash made up of large, flat blotches. The rash usually appears 14 days after exposure, starts at the hairline and spreads down the body. Some immunocompromised people may not develop the rash. A person is generally contagious the four days before and four days after the onset of a rash.
Many health departments and community health centers provide free MMR vaccinations for all, regardless of insurance status. The Illinois Department of Public Health has a vaccination locator here.
All people 12 months or older who plan to travel internationally should ensure that they have received 2 doses of MMR at least 2 weeks prior to travel. People who are frequently around international travelers, such as taxi drivers or those who work at airports should also double check their vaccination status, as their risk of exposure to measles is heightened.
Individuals who may have been exposed should notify their healthcare provider to determine the need for testing. If symptoms develop, they should notify their healthcare provider before going to a medical office or emergency department to prevent other patients and medical staff from possible exposure. Exposed individuals that are unvaccinated should talk with their doctor about getting MMR vaccine, doing so may prevent severe measles if given early enough after exposure.
As one of the most contagious diseases in the world, measles spreads easily through the air when an infected person breathes, coughs, or sneezes. If one person has measles, up to nine out of ten unprotected individuals nearby may become infected.
The measles virus severely weakens the immune system by wiping out up to 73% of the antibodies that defend against diseases a person was previously immune to. Measles can also cause severe complications, including blindness, brain damage, and even death.
Only the measles, mumps, and rubella (MMR) vaccine can prevent the disease. The measles vaccine is highly safe and effective. A single dose provides 93% immunity, while two doses increase protection to 97%, and generally provides lifelong immunity. Vitamin A is not a substitute for vaccination. Vitamin A supplementation does not prevent measles infection and can damage the liver.
Most Americans are vaccinated against measles routinely in childhood. The first dose should be given between 12-15 months of age and the second between the ages of 4-6 years old. If you were vaccinated before 1968, check with your healthcare provider about a revaccination.
Parents, when you take your child to the pediatrician for their school physical, remember this: the measles vaccine protects your child, and the children in their class, from getting sick. 2026 has already broken the record for the highest number of U.S. measles cases, and we still have five months to go.
Learn more on how to keep your children safe this upcoming school year below.