Rebecca Ann Lowe, age 9, of Cumberland, Md., for her question:

WHAT IS RUBELLA?

Rubella is a highly contagious but usually mild disease. It is also called German measles or three day measles.

First symptoms of the disease appear about two weeks after exposure. They may include ;mild throat soreness, fever and a runny nose. About a day later, a pink rash usually appears on the face and other parts of the body. The lymph glands behind the ears may become enlarged and tender.

Although the symptoms of German measles last only two or three days in most cases, the patient may be infectious from about seven days before to about five days after the rash appears.

Few people have German measles more than once. Also, a vaccine is available that provides immunity.

Children usually come down with German measles. But the disease also can strike adults. It is particularly dangerous during pregnancy. If a woman gets the disease during the first three months of pregnancy, the disease increases the chance that her baby will be born with a number of defects.