27/02/2022
Causes
Measles is a highly contagious illness caused by a virus that replicates in the nose and throat of an infected child or adult. Then, 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.
About 90% of susceptible people who are exposed to someone with the virus will be infected.
Risk factors
Risk factors for measles include:
Being unvaccinated. If you haven't received the vaccine for measles, you're much more likely to develop the disease.
Traveling internationally. If you travel to developing countries, where measles is more common, you're at higher risk of catching the disease.
Having a vitamin A deficiency. If you don't have enough vitamin A in your diet, you're more likely to have more-severe symptoms and complications.
Complications
Complications of measles 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 a complication called encephalitis. Encephalitis may occur right after measles, or it might not occur until months later.
Pregnancy problems. If you're pregnant, you need to take special care to avoid measles because the disease can cause preterm labor, low birth weight and maternal death.