1. What is rubella? Rubella is an infectious disease caused by the rubella virus. It usually causes mild fever, rash, and swollen lymph nodes. While rubella usually doesn\’t cause too much of a problem for adults, in pregnant women, infection with rubella can lead to miscarriage, stillbirth, or a baby being born with congenital rubella syndrome. 2. What does the picture of infant rubella look like?