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Public Health - Seattle & King County

Measles (Rubeola) fact sheet

What is it?

Measles is one of the most easily spread infections with potentially serious complications. It is caused by the measles virus.

  • Symptoms start about 10 -21 days after exposure and the illness lasts from 1-2 weeks.
  • The illness starts with a runny nose, watery eyes, cough, and high fever.
  • In the first few days, tiny white spots appear inside the cheeks.
  • After 2 to 4 days, a raised, red rash starts on the face and spreads down the body and out to the arms and legs. The rash usually lasts 4 to 7 days and appears about 14 days after exposure.
  • People with measles are contagious for 4 days before and at least 4 days after the rash begins.
Potential complications
  • Measles is sometimes complicated by ear infections, pneumonia, or encephalitis (inflammation of the brain) which can lead to convulsions, deafness, or mental retardation.
  • Measles can cause miscarriages or premature delivery in pregnant women.
How is it spread?
  • The virus is in secretions from the nose or throat of a person with measles, or on objects contaminated with those secretions.
  • The measles virus can also spread through the air on small droplets expelled when an infected person sneezes or coughs. People become infected when the droplets are breathed in or land on their nose or mouth.
Who is at highest risk?
  • Infants who are too young to have been immunized (less than 1 year of age).
  • Those who waived vaccination against measles.
  • Persons who were vaccinated with an inactivated vaccine that was available from 1963-1967, and have not been re-vaccinated.
  • People born before 1957 are generally considered immune (protected and not at risk) because they probably had the disease.
  • Pregnant women who have never had measles or the measles vaccine and persons with weakened immune systems are at risk for serious complications from measles.
  • Measles can be prevented through vaccination. In Washington State, all children are required to have documented measles immunization for entry into a school or childcare center.
  • The most common measles vaccine is the MMR. It combines measles vaccine with the vaccines for mumps and rubella.
  • MMR is given to toddlers when they are 12 to 15 months of age. A second MMR is given at 4 to 6 years of age. The vaccine is very safe and does not cause autism.
  • People who have measles should limit their contact with others and avoid public places until at least 4 full days have passed since the time the rash first appeared.
  • People exposed to measles should consult their health care provider immediately. Measles vaccine given within three days of exposure can help prevent infection in healthy non-pregnant persons.
  • Ill people should stay home and avoid public places until they have consulted their health care provider. Be sure to call ahead before visiting your health care provider to avoid exposing other people in the waiting room.
  • Immune globulin is a medication that can be used within 6 days of exposure to protect high-risk people and household members who have been exposed to measles.

Report all King County cases to Public Health by calling 206-296-4774.

For King County health care providers: