Measles

Measles—also known as five-day measles, hard measles, red measles, or rubeola—is a highly contagious disease. Approximately 85 percent of people exposed to the virus will become infected. Measles is caused by a morbillivirus and is spread from the nose or throat of an infected individual through microdroplets passed by coughing or sneezing to another person. Symptoms usually appear within 10 to 18 days of initial exposure.

People with measles are most contagious from the week before their symptoms begin to appear to four days after they become symptomatic. The first symptoms commonly exhibited include a fever that can run as high as 105 degrees F (40.5 degrees C), runny eyes and nose, and a cough. A few days later, a rash appears in the mouth that ...