Public Health Alert: Possible risk of measles transmission from travelers at Sea-Tac Airport

The Seattle & King County Health Department was notified on Thursday, May 30, 2024, of a confirmed case of measles in an adult who traveled through Seattle-Tacoma International Airport while in an infectious state on May 10 and 11, 2024.

The person is an Arizona resident and was likely infected with measles during travel to or within Europe. The person’s vaccination status is unknown.

“Measles is highly contagious and if you don’t have immunity, you can get it just by being in a room where someone with measles has been,” said Dr. Eric Chow, chief of the communicable disease division at Seattle and King County Public Health. “We’ve seen an increase in measles cases worldwide and in the United States, so it’s important to check your vaccination status and get vaccinated if you’re not protected.

Fortunately, the measles vaccine is very effective. Two doses of the measles, mumps, and rubella (MMR) vaccine provide about 97% protection against measles infection, and this protection lasts a lifetime.”

Places with potential danger to the public

Transmission of measles can occur before people know they are sick and before a rash appears.

The infected person was in the following public places before being diagnosed with measles. These time periods include the time the person was in the place and two hours afterward. Measles virus can remain in the air for up to two hours after a person infected with measles leaves the place. Anyone who was in the following places during the times listed could have been exposed to measles:

What should you do if you are in a place where you may come into contact with measles?

Most people in our area are immune to measles through vaccination, so the risk to the general public is low. However, anyone who has been in places where they may have been exposed to measles during the times indicated should do the following:

• Find out if you have been vaccinated against measles or have had measles. Make sure you have received the recommended number of measles vaccines (MMR).
• Call a doctor immediately if you develop an illness with fever or an unexplained rash. To avoid possible transmission of measles to others, do not go to a clinic or hospital without calling first and saying that you want to be tested for measles after exposure. It is also important to limit contact with others, especially those without known immunity.

If you were in the places mentioned above during the times mentioned above and are not immune to measles, the highest probability of getting the disease is between May 17, 2024 and June 1, 2024. In people with weakened immune systems, symptoms may take longer to appear.

About measles

Measles is a highly contagious and potentially serious disease that causes fever, rash, cough, runny nose and red, watery eyes. When one person is infected, up to 9 out of 10 people nearby will become infected unless they are protected. The disease spreads mainly through the air when a person with measles coughs or sneezes.

Measles symptoms begin seven to 21 days after infection. Measles is contagious from about four days before the rash appears until four days after the rash appears. People can spread measles before they get the characteristic measles rash.

Measles can cause ear infections, diarrhea, pneumonia and, in rare cases, encephalitis (inflammation of the brain).

Complications from measles can also occur in healthy people. However, those most at risk are infants and children under five years of age, adults over 20 years of age, pregnant women and people whose immune systems are weakened due to medications or underlying diseases.

If you are in one of these high-risk groups and have been exposed to measles in one of these locations, be sure to contact your doctor to discuss any steps you need to take to protect yourself or your loved ones from complications from measles.

Measles can be prevented with the safe and highly effective measles, mumps, and rubella (MMR) vaccine. According to the Centers for Disease Control and Prevention (CDC), two doses of the MMR vaccine are about 97% effective at preventing measles, and this protection lasts a long time.

For more information about measles and measles vaccinations, including where you can get a measles vaccination: www.kingcounty.gov/measles.

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