(German Measles; 3-Day Measles)
(See also Rubella in Newborns.)
Rubella is a typically mild childhood infection that may, however, have devastating consequences for infants infected before birth. A woman infected during the first 16 weeks (particularly the first 8 to 10 weeks) of pregnancy often passes the infection to the fetus. This fetal infection causes miscarriage, stillbirth, or multiple, severe birth defects in the infant (referred to as congenital rubella syndrome).
Rubella used to be called "German measles" or "3-day measles" because it causes a rash similar to the rash caused by measles. However, it is caused by a different virus.
Rubella was once common during spring, with major epidemics infecting millions of people every 6 to 9 years. The disease is now rare in the United States because of widespread vaccination. Nonetheless, some young adult women have never had rubella or rubella vaccination and are thus at risk of having children with serious birth defects if they become infected during early pregnancy. Since 2004 in the United States, all cases of rubella have been imported by travelers or immigrants and rarely spread to other people.
Rubella is spread mainly by breathing in small virus-containing droplets of moisture that have been coughed into the air by an infected person. Close contact with an infected person can also spread the infection. People who have rubella are most contagious from several days before to 1 week after the rash appears, and the infection is usually spread while the rash is present. An infant infected before birth can spread the infection for many months after birth. A person who has had rubella develops immunity and usually cannot contract it again.
Rubella symptoms differ somewhat between children and adults.
Symptoms of rubella begin about 14 to 21 days after infection. Adults and some children feel mildly ill for a few days, with a low fever and irritated eyes. But in most children, the first sign is the characteristic rash.
The rash of rubella is similar to the rash caused by measles but is not as extensive and does not merge to form large red areas. The rash begins on the face and neck and quickly spreads to the trunk, arms, and legs. As the rash appears, a mild reddening of the skin (flush) occurs, particularly on the face. Painless spots appear on the roof of the mouth. These spots later merge with each other into a red blush extending over the back of the throat. The rash lasts about 3 to 5 days.
People with rubella usually do not feel very ill, but some have joint pain. Adults may develop fever, headache, and stiff, swollen joints (arthritis). Adults and some children may have swollen lymph nodes in the neck and back of the head. In rare instances, people develop a middle ear infection (otitis media) or a low platelet count (thrombocytopenia). Brain infection (encephalitis) is a very rare, but occasionally fatal, complication.
Doctors suspect rubella in people who have swollen glands at the back of their head and the characteristic rash. A definite diagnosis of rubella is necessary for pregnant women, people who have encephalitis, and newborns. The rubella diagnosis can be confirmed by measuring levels of antibodies to rubella virus in the blood or by testing throat, nose, or urine specimens.
Before birth, the diagnosis may be made in the fetus by testing the amniotic fluid or the fetus's blood. Pregnant women are routinely screened with blood tests during early pregnancy to confirm they are immune to rubella.
The first dose of the rubella vaccine, one of the routine immunizations of childhood, is given between 12 months and 15 months of age. The second dose is given between 4 years and 6 years of age. This vaccine provides immunity for 15 years or longer in more than 95% of people. The vaccine that is used is a combined vaccine. The combination contains measles, mumps, and rubella (MMR) vaccine, and sometimes also varicella (chickenpox) vaccine. There is no longer any separate vaccine just for rubella.
If doctors are not sure that certain adolescents and adults had both doses of vaccine, the doctors either give those people one dose of vaccine or do a blood test to detect antibodies to rubella (proof of immunity). People for whom doctors must be certain are
Examples include all women of childbearing age, health care workers, college students, and military recruits. If the blood test does not show proof of immunity, people are given one dose of vaccine unless they are pregnant. Pregnant women should not receive the rubella vaccine because the vaccine contains a living (but weakened) virus that may infect the fetus. Although the weakened virus does not appear to cause congenital rubella syndrome, it rarely may damage the fetus. Instead, pregnant women who are not immune should avoid anyone who has the illness and then be given the vaccine immediately after giving birth so that they will be immune during any future pregnancies. Because of the risk of infecting the fetus, all women who are given the rubella vaccine should make sure they do not become pregnant for at least 28 days after vaccination.
There is no treatment for rubella infection. Most people recover fully without treatment. Acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can be given for fever and aches. No treatment is available for encephalitis, which must just run its course with supportive care.