Abstract
A micro test for the detection of rubella IgG antibody by passive haemolysis in free solution (MIH) is presented. The technique is reproducible, sensitive, simple to perform and economical in the use of reagents. Identical results were obtained in all but one of 408 tests on serum specimens screened for rubella antibody at 15 i.u./ml by the MIH and haemagglutination inhibition (HI) techniques. The quantitative potential of the MIH test and the relative merits of the MIH, HI and radial haemolysis (RH) procedures for rubella screening are discussed.