Abstract
A solid-phase reverse immunosorbent test (SPRIST) based on the addition of an excess of rubella virus hemagglutinin was evaluated for the demonstration of rubella-specific IgM and the results were compared with those of the density gradient centrifugation technique. In a retrospective study in which 157 sera were tested, the 2 techniques yielded identical results (55 IgM-positive and 102 IgM-negative samples). In a prospective study, 592 sera were examined; 8 IgM-positive results by SPRIST corresponded to a recent rubella infection or vaccination. Neither rheumatoid factor nor heterophil antibody seemed to interfere with the results of SPRIST. This test would be a useful and rapid routine technique for demonstration of the presence of virus-specific IgM in serum samples, particularly for viruses with a hemagglutinin. Except for anti-human IgM, no more reagents are needed than for widely used hemagglutination inhibition procedures.