Rubella

A viral infection, also known as German measles. It is serious only if it affects a nonimmune woman in the early months of pregnancy, when there is a risk that the virus will cause severe birth defects in the fetus. The rubella virus is spread by motherto-baby transmission and in airborne droplets; it has an incubation period of 2–3 weeks. Infection usually occurs in children aged 6–12. A rash appears on the face, spreads to the trunk and limbs, then disappears after a few days. There may be slight fever and enlarged lymph nodes at the back of the neck. The virus may be transmitted from a few days before symptoms appear until one day after they disappear. An unborn baby is at risk if the mother is infected during the first 4 months of pregnancy. The earlier the infection occurs, the more likely the infant is to be affected, and the more serious the abnormalities tend to be. The most common abnormalities are deafness, congenital heart disease, learning difficulties, cataracts, purpura, cerebral palsy, and bone abnormalities. About 1 in 5 affected babies dies in early infancy. There is no specific treatment, apart from paracetamol for fever. Treatment of rubella syndrome depends on the defects. Rubella vaccine provides longlasting immunity to the disease; it is given in the MMR vaccine to babies aged 12–15 months, with a booster at school entry. Rubella infection also provides immunity. If a nonimmune pregnant woman comes into contact with a person who has rubella, passive immunization by immunoglobulin injection may help prevent infection of the fetus.