Many people consider measles and rubella to be the same, but there are fundamental differences between them:

Measles: The fever is usually high, the rash lasts for 5–7 days, leaves dark marks on the skin, and may lead to complications such as pneumonia or diarrhoea.

Rubella (German measles): The fever is generally mild, the rash lasts about three days, does not leave marks on the skin, but can cause serious harm to an unborn child during pregnancy.