About Measles

Key points

  • Measles is very contagious and can be serious.
  • Anyone who is not protected against measles is at risk.
  • Two doses of MMR vaccine provide the best protection against measles.
measles under a microscope

What it is

Some people think of measles as just a little rash and fever that clear up in a few days. But measles can cause serious health complications, especially in children younger than 5 years old.

Measles is highly contagious. If one person has it, up to 9 out of 10 people nearby will become infected if they are not protected.

The best protection against measles is measles, mumps, and rubella (MMR) vaccine. MMR vaccine provides long-lasting protection against all strains of measles.

Signs and symptoms

Measles symptoms appear 7 to 14 days after contact with the virus. Common measles symptoms include:

  • High fever (may spike to more than 104° F)
  • Cough
  • Runny nose (coryza)
  • Red, watery eyes (conjunctivitis)
  • Rash

Complications

Measles can cause serious health complications, especially in children younger than 5 years of age. Common complications are ear infections and diarrhea. Serious complications include pneumonia and encephalitis.

Who is at risk

Anyone who is not protected against measles is at risk.

Measles was declared eliminated from the United States in 2000. However, measles is still common in many parts of the world. Every year, measles is brought into the United States by unvaccinated travelers who get measles while they are in other countries. These travelers are mostly Americans and sometimes international visitors.

Some people are a higher risk of experiencing severe complications from measles.

How it spreads

Measles is very contagious. It spreads through the air when an infected person coughs or sneezes. You can get measles just by being in a room where a person with measles has been. This can happen even up to 2 hours after that person has left.

Keep Reading: How Measles Spreads

Prevention

Protect yourself with the vaccine. The best way to protect against measles is with the measles, mumps, and rubella (MMR) vaccine. MMR is safe and effective. Two doses of MMR vaccine are about 97% effective at preventing measles; one dose is about 93% effective.

Prevent measles and talk to your healthcare provider about the MMR vaccine, especially if planning to travel.

Keep Reading: Measles Vaccination