Rubella is a contagious infection that occurs most often in children and young adults. Symptoms of the disease include rash, low fever, nausea, swollen lymph glands behind the ears and in the neck, and mild pink eye. In adults, symptoms may also include arthritis and painful joints. While rubella is generally mild in children, it can have serious consequences in pregnant women. Pregnant women who are infected early in pregnancy have a 90% chance of passing the virus onto the fetus, which can cause miscarriage, stillbirth, fetal death, or severe birth defects known as congenital rubella syndrome. Rubella is preventable by vaccination.