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Measles is a highly contagious and potentially severe disease that causes fever, rash, cough, and red, watery eyes. It is mainly spread through the air after a person with measles coughs or sneezes.
  • Symptoms start about 7–21 days after being exposed to the virus, and the illness lasts from 1 to 2 weeks.
  • Measles starts with a runny nose, watery eyes, cough, and high fever.
  • After 2 to 4 days, a bumpy, red rash appears. It typically starts on the face and spreads down the body and then to the arms and legs. The rash usually lasts 4 to 7 days.

Measles is more contagious than almost any other disease. The virus that causes measles lives in the nose and throat of infected people. It is sprayed into the air when an infected person sneezes, coughs or talks. The virus can stay in the air for up to two hours. People with measles can spread the disease starting four days before the rash begins until four days after it appears.

  • those who are unvaccinated,
  • pregnant women,
  • infants under six months of age
  • and those with weakened immune systems.

Measles is diagnosed from a blood test, testing a swab of the inside of the nose and testing the urine for the virus. Usually all these tests are done at one time.

There is no specific treatment for measles. Vaccination is the best protection to prevent catching the disease.

  • Children should be vaccinated with two doses of the Measles Mumps Rubella (MMR) vaccine. The first dose should be given at 12 - 15 months of age, and the second dose at 4 - 6 years of age.

  • Infants traveling outside the United States can be vaccinated as early as 6 months of age but they must still receive the full two dose series beginning at 12 months of age.

  • Adults should have at least one dose of measles vaccine, and two doses are recommended for international travelers, healthcare workers, and students in college, trade school, and other schools after high school.

According to the Washington Administrative Code WAC 246-105-080, students and staff at any childcare facility or school in King County who have been exposed to measles and are not immune are required to stay home during the period of time in which they may develop the disease:

  • They must stay home starting seven days after first exposure through 21 days after the last exposure.
  • It's important that they stay home from all public activities, not just school and childcare.
  • Staying home greatly reduces the risk that the disease will spread to others who are unprotected, such as infants and pregnant women.

When a case of measles is confirmed in a childcare facility or school, Public Health investigates and confirms when the infected person attended the childcare facility or school.

If the infected person attended childcare or school while contagious, the childcare facility or school gives Public Health a list of all individuals who may have been exposed to the infected individual.

Anyone who cannot provide acceptable evidence of vaccination for measles or already having measles disease will be excluded from the childcare facility or school. Evidence of immunity could include documentation of dates the vaccines were given from a doctor or documentation of blood tests that show that a person has already had the vaccine or measles disease.

Number of cases of measles that have to occur in a childcare or school before children and staff who are not immune will be excluded

Because measles is one of the most contagious diseases, anyone not immune to measles will need to be excluded when one case is identified.

Generally it is not necessary to close childcare facilities or schools during a measles outbreak. However, it may be necessary to close a childcare facility or school if there are not enough providers/teachers or enough students to safely and effectively operate the school or childcare facility. This would be a decision made by the facility or school.

Overall, the county's measles, mumps and rubella (MMR) vaccination rate for kindergartners is about 91%, but rates in some neighborhoods and schools are much lower.

Health care providers can play a crucial role in parental decision making. They are the most frequent source of immunization information according to parents, including parents of unvaccinated children. Public Health works closely with health care providers to increase the number of vaccinated children. The health department provides school immunization coverage information so that schools and parents can be aware of vaccination levels and work to make improvements where needed. Public Health also offers materials and resources to effectively address parents' questions and concerns about vaccines.

Public Health partners with organizations such as the Immunization Action Coalition of Washington, VaxNorthwest and the Group Health Foundation to increase public awareness about the importance of immunizations.