Single-radial-hemolysis test for the assay of rubella antibody in antenatal, vaccinated, and rubella virus-infected patients.

The single-radial-hemolysis test (SRHT) is a simple, convenient, and sensitive method that provides accurate measurement of IgG antibody to rubella virus. Lipoprotein inhibitors of rubella hemagglutination do not interfere with the SRHT; thus the assay of low levels of antibody is more reliable by SRHT than by the rubella hemagglutination-inhibition test (RHIT). The technique for the SRHT in a form suitable for large numbers of tests is detailed and compared with that of the RHIT, and the reproducibility of the SRHT in routine operation is assessed. Results obtained by testing various populations in Western Australia are used to show the application of the SRHT in the diagnosis of rubella and in the monitoring of rubella vaccination programs.