[Appearance and persistence of rubella-specific IgM antibodies (author's transl)].

In order to investigate the validity of rubella-specific IgM antibodies for current or recent infections serum samples of 103 persons were investigated after natural infection or immunisation. 41 patients with natural infections and 7 immunised persons could be observed until complete disappearance of IgM antibodies. In all cases rubella-specific IgM could be demonstrated up to 10 weeks after infection. The percentage of positive findings decreased gradually thereafter. Lower concentrations of rubella IgM were demonstrable for several months after infection in some cases and for as long as 379 days in one case. The concentration of specific IgM antibodies was shown to be very high for the first 50 days after infection whereas only low concentrations were found after the 80th day.