Measles, also called rubeola, is a viral infection best known for its typical skin rash. It is, however, primarily a respiratory infection. The first symptoms are irritability, runny nose, eyes that are red and sensitive to light, hacking cough, and a fever as high as 105 degrees Fahrenheit (40.6 degrees Celsius).

Fever peaks with the appearance of the rash, which typically begins on the forehead, then spreads downward over the face, neck, and body. The child is particularly ill-looking during the first days of the rash. It usually takes about 3 days for the rash to make its way down to the feet. Once the rash appears on the legs and feet, symptoms usually subside within 2 days.

The rash itself looks like large flat red to brown blotches that often flow into one another to completely cover the skin, especially on the face and shoulders. The rash fades in the same order that it appeared, forehead first and feet last. The total time for the rash, from beginning to end, head to toe, is usually about 6 days. As the rash disappears, the healing skin may look brown temporarily, before it sheds in a finely textured peel.