Measles in Boulder County

Measles spreads through the air and can also live on surfaces for up to two hours. Measles causes fever, cough, runny nose, red, watery eyes, and rash.

Measles can lead to serious health problems like pneumonia, brain swelling, hearing loss, and sometimes death. Babies, young children, pregnant people, older adults, and people with weakened immune systems are at a higher risk of getting very sick.

About Measles (CDC)

Symptoms of measles generally show up 7 to 12 days (up to 21 days) after possible contact with someone who has the virus. Early symptoms include:

• High fever (sometimes above 104°F)
• Cough
• Runny nose
• Red, watery eyes

Two to three days after symptoms begin, small white spots – known as Koplik spots – may show up inside the mouth.

Three to five days after the first symptoms appear, a rash develops. It usually begins at the hairline and spreads down to the face, neck, trunk, arms, legs, and feet. As the rash appears, the fever may rise even higher.

• See photos of measles rashes

Prevent Measles with the MMR Vaccine

The measles, mumps, and rubella (MMR) vaccine is the best way to prevent measles. One dose is about 93% effective at preventing infection. Two doses provide about 97% defense against getting measles and lifelong protection for most people.

• Children: The first dose should be given at 12 to 15 months old, and then a second dose at 4 to 6 years old.
• Adults: Anyone born after 1957 should make sure they have had two doses of the MMR vaccine or have had a lab test to check for immunity.
• Babies: Children ages 6 to 11 months should get one early dose of the MMR vaccine before travel outside the US.
• Adults vaccinated between 1963 and 1967: Some people got a less effective version of the vaccine. Talk with your healthcare provider to learn if another dose is needed.

If you are not sure if you got the MMR vaccine, it is safe to get another dose.

• Measles Vaccination Guidance (State of Colorado)

Measles Contact with Symptoms

If you think you or your child may have come in contact with someone who has measles and you see signs of measles:

• Call your healthcare provider right away.
• Do not visit a clinic or doctor’s office without calling ahead first. This can help stop the virus from spreading to others.
• Stay home and avoid other people.
• If you must be around others, wear a mask.

People with measles can spread it to others starting four days before the rash appears and up to four days after.

Measles Contact without Symptoms

People who think they may have been exposed to measles but are not showing symptoms should take steps to protect themselves and others.

• Unvaccinated people or people who are unsure if they’re immune should contact their healthcare provider. They may need a post-exposure vaccine or immune globulin.
• In some cases, people may need to stay out of school, work, or other group settings for up to 21 days.

What to do if you may have been exposed and aren’t feeling well (State of Colorado)

Measles remains a common disease in many parts of the world, with cases continuing to be reported across the United States. International travel greatly increases the risk of exposure. People who are not protected against measles can become infected while traveling and may spread the virus when they return.

Before Travel

Make sure all travelers are fully vaccinated with the MMR vaccine.

• Children should receive their first MMR dose between 12 and 15 months and a second dose between 4 and 6 years.
• Infants ages 6 to 11 months should get one early dose before traveling internationally.
• Adults should have proof of two MMR doses or a lab test that shows they are protected.

If you are unsure of your vaccination status, consult your health care provider. A simple blood test can confirm immunity, or you may be able to safely receive another dose.

Travelers who are unvaccinated or under vaccinated put others at risk—especially infants, older adults and people with weakened immune systems.

• Plan for travel (CDC)

Stay informed with the latest updates from Boulder County Public Health on measles and other key health topics.

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