Rubella virus causes German measles, a mild rash disease which commonly occurs during childhood. It is highly contagious and mainly transmitted by the respiratory route.1 Rubella can also occur vertically from an infected mother to her child.1 Postnatal infection is rarely associated with complications, however, primary infection mainly during early pregnancy is a serious condition, as it may cause miscarriages or congenital rubella syndrome (CRS). CRS includes blindness, deafness, congenital heart disease and mental retardation.1
Today’s vaccination programs have considerably reduced the incidence of acute rubella and CRS.2 Since rubella may present atypically or with non-specific symptoms and signs that may be caused by other viruses which do not have a teratogenic potential, it is important that the clinical diagnosis be confirmed by laboratory tests, particularly during pregnancy.3
Seroconversion of specific rubella antibodies or a significant rise of the IgG titer strongly supports the diagnosis of acute rubella infection.3 The presence of IgG antibodies to rubella virus indicates a previous exposure either by vaccination or prior rubella infection and suggests immunity.3 The quantitative determination of specific IgG is used to determine the immune status to rubella.3