Boy with a rash caused by measles. Measles is viral infection, considered a childhood illness, that is now preventable by vaccine. Symptoms include fever, cough, sore and reddened eyes, followed by a red brown rash that first appears on the face and spreads down the body. The incubation period between infection and the onset of the first symptom is about 10 days. The infected person is contagious before the first symptom appears. Although there is no treatment except bed rest, most children recover with no ill effects.