Definition
Rubella is caused by the rubella virus, which belongs to the toga virus family. Rubella belongs to the childhood diseases. The typical peak age is between 5 and 9 years, but adults can also be affected.
In recent years, an increasing number of infections have been observed in young adulthood. The infection is particularly dangerous during pregnancy. Pregnant women are therefore particularly at risk if there are gaps in vaccination coverage. After a rubella infection, there is life-long immunity. In the case of an outbreak of rubella, there is an obligation to report the infection.
Causes
An infection with rubella occurs via a so-called droplet infection from person to person. The pathogens in the saliva or nasal secretion are transmitted to another person when coughing or sneezing. Humans are the only known host.
The rubella virus is absorbed via the respiratory tract and initially multiplies in lymph node stations before spreading further in the blood. There is a risk of infection approximately one week before and one week after the appearance of the rash. However, the actual risk of infection is generally not considered to be very high.
A special form of infection exists during pregnancy. If the mother is infected with rubella, she can transmit the virus via the blood of the placenta to the unborn child. The sick children can be contagious for up to one year after birth.
Symptoms
Before the typical rash develops, those affected feel flabby and show signs of a mild cold. The typical rubella rash (exanthema) begins on the head, usually behind the ears, and spreads from there over the whole body including the extremities. It is composed of fine to medium-spotted red spots. These are light red and are usually well distinguishable from each other. The rash is called fleeting, because it usually disappears after a few days.
History
The course of a rubella infection is in most cases harmless and very mild. In half of the cases there is no outbreak at all. Complications occur mainly in adulthood.
They range from joint pain to very painful inflammation of the joints (arthritis). These can persist even weeks after the rash has subsided. The general inflammatory reaction can also spread to a variety of organs.
Inflammation of the middle ear or bronchitis occurs regularly. Particularly dangerous is an inflammation of the brain in the form of encephalitis or an inflammation of the heart muscle or pericardium in the form of myocarditis or pericarditis. In the aftermath of the infection, there may be a drop in the blood platelets (thrombocytopenia), which in turn provokes tiny bleedings in the skin.
The course of the disease is particularly dramatic during pregnancy. An abortion or premature birth can be the consequences. The extent of the complications varies depending on the time of illness.
Particularly in the first ten to twelve weeks of pregnancy, there is a 50% probability of transmission from mother to child and thus a full-blown rubella embryopathy. This so-called Gregg triad consists of heart defects, clouding of the lens (cataract) and sensorineural hearing loss. A limitation of cognitive abilities (mental retardation) is also possible. After the first trimester, blood count changes, inflammation of the liver (hepatitis) or enlargement of the spleen (splenomegaly) can occur in the course of rubella fetopathy.
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