What is it?
Measles is a common childhood disease that now can be prevented with a vaccine. Signs and symptoms of measles include cough, runny nose, inflamed eyes, sore throat, fever and a red, blotchy skin rash.
Also called rubeola, measles can be serious and even fatal for small children. While death rates have been falling worldwide as more children receive the measles vaccine, the disease still kills several hundred thousand people a year, most under the age of 5.
Measles symptoms and signs appear 10 to 12 days after exposure to the virus. They typically include:
- Dry cough
- Runny nose
- Inflamed eyes (conjunctivitis)
- Sensitivity to light
- Tiny white spots with bluish-white centers found inside the mouth on the inner lining of the cheek, called Koplik's spots
- A skin rash made up of large, flat blotches that often flow into one another
The course of the measles virus
Measles typically begins with a mild to moderate fever, accompanied by other signs and symptoms, such as a persistent cough, runny nose, inflamed eyes (conjunctivitis) and sore throat. Two or three days later, Koplik's spots — a characteristic sign of measles — appear. Then a fever spikes, often as high as 104 or 105 °F (40 or 40.6 °C). At the same time, a red blotchy rash appears, usually on the face, along the hairline and behind the ears. This slightly itchy rash rapidly spreads downward to the chest and back and, finally, to the thighs and feet. After about a week, the rash fades in the same sequence that it appeared.
The cause of measles is a very contagious virus, which lives in the mucus in the nose and throat of an infected child or adult. That child or adult is contagious from four days before the rash appears to four days after.
When someone with measles coughs, sneezes or talks, infected droplets spray into the air, where other people can inhale them. The infected droplets may also land on a surface, where they remain active and contagious for several hours. You can contract the virus by putting your fingers in your mouth or nose or rubbing your eyes after touching the infected surface.
- No vaccination. People who have not received the vaccine for measles are much more likely to develop the disease.
- International travel. Unvaccinated people travelling to developing countries, where measles is more common, are at higher risk of catching the disease.
- Vitamin A deficiency. People who don't have enough vitamin A in their diets are more likely to contract measles and to have more-severe symptoms.
Most people recover from measles in 10 to 14 days. As many as 20 percent will develop complications, which may include:
- Ear infection. One of the most common complications of measles is a bacterial ear infection.
- Bronchitis, laryngitis or croup. Measles may lead to inflammation of your voice box (larynx) or inflammation of the inner walls that line the main air passageways of your lungs (bronchial tubes).
- Pneumonia. Pneumonia is a common complication of measles. People with compromised immune systems can develop an especially dangerous variety of pneumonia that is sometimes fatal.
- Encephalitis. About 1 in 1,000 people with measles develops encephalitis, an inflammation of the brain that may cause vomiting, convulsions and, rarely, coma or even death. Encephalitis can closely follow measles, or it can occur years later.
- Pregnancy problems. Pregnant women need to take special care to avoid measles, because the disease can cause miscarriage, premature labor or babies with low birth weights. Rubella, or German measles, is a separate disease that can cause birth defects during pregnancy.
- Low platelet count (thrombocytopenia). Measles may lead to a decrease in platelets — the type of blood cells that are essential for blood clotting.
Your doctor can usually diagnose measles based on the disease's characteristic rash as well as the small, bright red spots with bluish-white centers on the inside lining of the cheek, called Koplik's spots. If necessary, a blood test can confirm whether the rash is truly measles.