A new latex agglutination test for rubella virus was used to test sera with a hemagglutination inhibition titer of less than or equal to 8 (97 specimens) or greater than or equal to 256 (158 specimens). Maximum latex agglutination test sensitivity was achieved when low-titer sera were tested undiluted and high-titer sera were diluted (1:10). A modification of the protocol of the manufacturer re...