Measles
Based on CDC and WHO guidance, checked against those sources on Oct 12, 2026. Educational information only — not a diagnosis or a substitute for a licensed healthcare professional.
1 · Prevention
- Make sure you and your family are protected: two doses of MMR vaccine are about 97% effective; one dose is about 93% effective.
- Check your vaccination records before international travel — measles is circulating in many countries.
- If you are unsure whether you are immune, ask a healthcare professional; a blood test or vaccination can resolve it.
Vaccines & preventive medicines
- MMR (measles-mumps-rubella) vaccine. Routine childhood schedules give two doses. CDC recommends that babies 6–11 months old get one dose before international travel, then the usual two doses after their first birthday. Adults without evidence of immunity may need one or two doses. A healthcare professional can advise.
- After an exposure, MMR vaccine given within 72 hours, or immune globulin given within 6 days to certain high-risk people who cannot have the vaccine, may prevent measles or make it milder. Only a healthcare provider or health department can decide who qualifies and arrange this.
2 · Possible exposure
- Call a healthcare provider or your local health department right away — tell them you may have been exposed to measles. Call before you visit so they can protect others in the waiting room.
- Check whether you are protected (two documented MMR doses, or proof of past infection or immunity).
- Watch for symptoms for 21 days after the exposure.
- If you are not immune, health officials may ask you to stay home during the period you could become contagious.
3 · Symptoms or illness
- Call ahead before going to a clinic, urgent care or emergency room and say you might have measles.
- Stay home and away from others — especially babies, pregnant people and anyone with a weakened immune system — until at least 4 days after the rash appeared, or as directed by health officials.
- Rest, drink fluids, and follow your healthcare provider's advice. There is no specific antiviral treatment for measles. For children, a provider may give vitamin A.
- If any emergency sign below appears, go to the emergency room right away — don't wait — and have someone call ahead to say you may have measles.
Protect family & others
- Stay isolated while contagious.
- Tell close contacts and the health department so exposed people can get preventive vaccination in time.
- Make sure everyone in your household is up to date with MMR.
- Isolation usually lasts through the fourth day after the rash appears. Health departments may set specific dates — follow their instructions.
Groups at higher risk of severe illness
- Children younger than 5
- Adults older than 20
- Pregnant people
- People with weakened immune systems
- Anyone who is not vaccinated