Measles is one of the most contagious diseases in the world, transmitted through contact with infected nasal or throat secretions (from coughing or sneezing) or by inhaling air breathed by a person with measles. The virus remains active and contagious in the air or on infected surfaces for up to two hours. Because of this, it is highly contagious, and one person infected with measles can infect 9 out of 10 unvaccinated individuals who are in close contact with them. The measles virus can be transmitted by an infected person from 4 days before the rash appears to 4 days after it starts.

Anyone can contract measles, but it is most common in children.

Measles affects the respiratory system and then spreads throughout the body. Symptoms include high fever, cough, runny nose, and a rash covering the entire body.

The most effective way to prevent measles and its transmission is through vaccination. The vaccine is safe and helps the body fight the virus.

Signs and Symptoms

Measles symptoms usually appear 10–14 days after contact with the virus. The most noticeable symptom of measles is a pronounced rash.

Early symptoms typically last 4–7 days and include:

• runny nose;
• cough;
• red eyes and tearing;
• small white spots inside the cheeks.

The rash appears about 7–18 days after contact with the virus, usually on the face and upper neck. It spreads over about 3 days, eventually covering the arms and lower limbs. After 5–6 days, the rash fades and disappears.

Most fatal cases of measles are due to complications.