Measles, also known as rubeola, is a disease caused by a virus of the genus Morbillivirus.
In 1954, the virus causing the disease was isolated, and licensed vaccines to prevent the disease became available in 1963.
Measles is spread through respiration (contact with fluids from an infected person's nose and mouth, either directly or through aerosol transmission), and is highly contagious - 90% of people without immunity sharing a house with an infected person will catch it.
Airborne precautions should be taken for all suspected cases of measles.
The incubation period usually lasts for 4-12 days (during which there are no symptoms).
Infected people remain contagious from the appearance of the first symptoms until 3-5 days after the rash appears.