The detection of specific IgM antibodies following infection with rubella virus.

A gel filtration technique using Sephadex G-200 has been used for the detection of specific IgM in sera from (a) 45 cases of clinical rubella in which diagnostic rises of rubella haemagglutination-inhibiting (HAI) antibody could be demonstrated; (b) 70 cases with clinical evidence of rubella in which a rising titre could not be demonstrated because the first serum sample already had high titre HAI antibodies; and (c) 100 patients in whom rubella was not suspected. The results indicate that the high specificity and sensitivity of the method described make it an appropriate technique for use in the routine diagnosis of acquired rubella.