Questions & Answers

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What causes rubella?
Rubella is caused by a virus.

How does rubella spread?
Rubella spreads from person to person through the air. Rubella is contagious but less so than measles and chickenpox.

How long does it take to show signs of rubella after being exposed?
The incubation period varies from 12 to 23 days (average, 14 days). Symptoms are often mild and may be inapparent up to half of the time.

What are the symptoms of rubella?
Children with rubella usually first break out in a rash, which starts on the face and progresses down the body. Older children and adults usually first suffer from low-grade fever, swollen glands in the neck or behind the ears, and upper respiratory infection before they develop a rash. Adult women often develop pain and stiffness in their finger, wrist, and knee joints, which may last up to a month. Up to half of people infected with rubella virus have no symptoms at all.

How serious is rubella?
Rubella is usually a mild disease in children; adults tend to have more complications. The main concern with rubella disease, however, is the effect it has on an infected pregnant woman. Rubella infection in the first trimester of pregnancy can lead to fetal death, premature delivery, and serious birth defects.

What are possible complications from rubella?
Encephalitis (brain infection) occurs in one in 6,000 cases, usually in adults. Temporary blood problems, including low platelet levels and hemorrhage, also occur rarely. Up to 70% of adult women with rubella have pain and/or swelling of the joints, which is usually temporary.

The most serious complication of rubella infection is Congenital Rubella Syndrome (CRS), the result when the rubella virus attacks a developing fetus. Up to 85% of infants infected during the first trimester of pregnancy will be born with some type of birth defect, including deafness, eye defects, heart defects, mental retardation, and more. Infection early in the pregnancy (less than 12 weeks gestation) is the most dangerous; defects are rare when infection occurs after 20 weeks gestation.

Is there a treatment for rubella?
There is no "cure" for rubella, only supportive treatment (e.g., bed rest, fluids, and fever reduction).

How do I know if my child has rubella?
Because the rubella rash looks similar to other rashes, the only sure way to diagnose rubella is by a laboratory test.

How long is a person with rubella contagious?
The disease is most contagious when the rash is erupting, but the virus can be spread from seven days before, to 5-7 days after the rash begins.

If I think my child has been exposed to rubella, what should I do?
If your child has not been vaccinated against rubella, receiving the vaccine after exposure to the virus will not help prevent disease if the child has already been infected. However, if the child did not become infected after this particular exposure, the vaccine will help protect him or her against future exposure to rubella.

How common is rubella in the United States?
Due to good immunization coverage, rubella and CRS are rare in the United States at the present time. However, outbreaks continue to occur in groups of susceptible individuals who refuse immunization for religious or philosophic reasons and among some foreign-born immigrants, who come from areas where rubella vaccine is not routinely used. Rubella can be imported into the United States at any time.

Rubella outbreaks are unfortunately followed by an increase in CRS. Two rubella outbreaks in 1990-1991, in California and Pennsylvania, resulted in the birth of 58 infants with CRS.

Can you get rubella more than once?
Second cases of rubella are believed to be very rare.

Why do people call rubella "German measles"?
Rubella was first described as a separate disease in the German medical literature in 1814.

Questions and answers about rubella vaccine

Technically reviewed by the Centers for Disease Control and Prevention, April 2007