Measles Home > Measles Incubation Period
When a person becomes infected with the measles virus, symptoms do not appear immediately. This period of time, when the virus is multiplying inside of the body and symptoms have not yet developed, is known as the incubation period. A person is not contagious during this incubation period for measles.
When a person becomes infected with the measles virus, it begins to multiply within the cells that line the lungs and the back of the throat. The virus can also spread to the:
After 8 to 12 days, on average, symptoms of measles can begin. The period between measles transmission and the start of symptoms is called the incubation period.
A person is not contagious during the measles incubation period. A person is mildly contagious when he or she first experiences symptoms, and is most contagious about four days before the onset of the measles rash. Some risk of measles transmission lasts until about four days after the rash starts.