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Last full review/revision Dec 2019| Content last modified Dec 2019
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What is measles?

Measles is a viral infection Overview of Viral Infections A virus is a tiny living organism. Viruses are so small they can be seen only with the most powerful microscopes. That's why they're called microorganisms (micro means very small). Other common... read more . It used to be very common in children in the United States. Measles is now rare in the United States because it's prevented by routine childhood vaccines. In parts of the world where fewer children are vaccinated, measles is still common.

What causes measles?

Measles is caused by a virus. Healthy children who haven't had the vaccine can get measles just by breathing in the virus after someone with measles coughs or sneezes near them.

What are the symptoms of measles?

The first symptoms start 7 to 14 days after infection:

  • Fever

  • Runny nose

  • Hacking cough

  • Red eyes

  • Sometimes, sensitivity to bright light

  • Tiny red spots with white or bluish-white centers inside the mouth

  • Sore throat

About 3 to 5 days later, your child may have:

What problems does measles cause?

How can doctors tell if my child has measles?

Doctors will do a physical exam. They'll look for:

  • Measles rash

  • Tiny red spots with blue or bluish-white centers in the mouth (Koplik spots)

Doctors will do blood tests to know for sure if your child has measles. If your child does, they'll tell public health officials, who will try to keep measles from spreading to too many people in your area.

How do doctors treat measles?

There's no treatment that will cure the measles. Have your child rest while the virus runs its course.

To help your child, you can:

How can I prevent measles?

  • Children get 2 measles shots total, at age 12 to 15 months and at age 4 to 6 years

  • Children as young as 6 months can get their first shot if needed, such as during a measles outbreak or before traveling outside the United States

  • The measles vaccine is part of the MMR shot, which is a vaccine that also protects against mumps and rubella

  • The MMR shot doesn’t cause autism

  • Some people may have a mild fever and rash after getting the vaccine

  • Certain people shouldn’t get the MMR shot, including pregnant women and people who are very sick or have a weak immune system

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