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Boy with measles rash

Is measles serious?

For most people who get measles, the illness is not serious. It starts with fever, cough, runny nose, and watery eyes. After a few days a rash develops and lasts about a week. Then, it gets better by itself. However for some people who get measles, the disease can be more serious.


What happens when the disease is more serious?

Measles can infect other parts of the body. About 8 per 100 people with measles get diarrhea (8%), 7 per 100 get a middle ear infection (mainly young children), and 6 per 100 get pneumonia (lung infection with breathing trouble).


About 1 in 1,000 people with measles get encephalitis, a serious brain infection. Measles illness during pregnancy can cause early labor, miscarriage, and low birth weight infants. Measles in people with AIDS or weak immune systems can be very severe. In the U.S. people can still die from measles (about 2 per 1,000, usually related to pneumonia or encephalitis).


Is there treatment for measles?

There is no medicine that kills the measles virus once someone develops measles. Most people with measles get better by themselves. They should rest, drink plenty of fluids, and can take acetaminophen (Tylenol) to help reduce the fever and feel more comfortable. People who are severely ill or who develop pneumonia, middle ear infection, or diarrhea should discuss treatment with their doctor. Although no medicine will make the measles virus go away, there may be a role for other medicines, such as antibiotics, in treating other possible reasons for infection.


How is measles spread or passed to others?

Measles is spread by bodily fluids - drops of saliva from the mouth, mucus from the nose, coughing or sneezing, and tears from the eyes. The measles virus can also float in the air for up to one hour after someone with measles coughs or sneezes indoors. Someone who breathes air containing the measles virus can get measles. People with measles can spread the disease to others from 4 days before the rash starts (before they know they have the disease), through 4 days after the rash begins.


What does it mean to be "exposed" to measles?

"Exposed" means you've been in a situation where you can catch the virus from someone who already has measles. For example, you can be exposed to the measles virus by being in the same room, home,office, or waiting room with someone who has measles or by being there up to one hour after the person with measles has left.


Is it true that some people can't get measles?

Yes. Some people are immune to measles, meaning that their body has already learned how to fight off the virus, and they won't become sick from it. People can become immune to measles in two ways. If they've already had measles earlier in life, then they are immune and won't get it again. Or, if they have gotten 2 doses of measles vaccine, they should be immune (protected from getting measles).


How do you know if someone is immune to measles?

The only way to tell for sure that a person is protected (immune) is by a blood test. The blood test shows whether the body has antibodies to fight off the virus. This is called laboratory evidence of immunity. Even if someone hasn't had the blood test, they are still considered immune if:

  • They had measles in the past, and have medical records to prove it, OR
  • They received 2 doses of measles-containing vaccine in the past (often given as MMR [measles-mumps-rubella] vaccine) and have medical records to prove it, OR
  • They were born before 1957


How well does the measles vaccine work?

The measles vaccine works extremely well. If 1,000 people each get 2 doses of measles vaccine, about 997 of them will be protected against measles (immune). Getting 2 doses of vaccine is important, because some people (about 2-5 per 100) do not become protected (immune) after just one dose of vaccine.  Read the measles vaccine fact sheet.  Find a vaccine provider in San Francisco.


Does the measles vaccine protect against other diseases too?

In the USA, measles vaccine is almost always given as a combination with vaccine against 2 other viruses: mumps and rubella. This combination vaccine is called MMR (measles, mumps, and rubella) and it gives protection against all 3 viruses.  Find a vaccine provider in San Francisco


Can pets get infected with measles or spread measles?

No, pets do not get infected with or spread the measles virus.


Additional Information - Measles

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Additional Information - Vaccination

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