HEMAGGLUTINATION BY THE KOCH-WEEKS BACILLUS (HEMOPHILUS AEGYPTIUS)

Abstract

Twenty-seven of 28 strains of Koch-Weeks bacillus (H. aegyptius) possessed an agglutinin for human red blood cells and some strains for the red cells of other spp. H. influenzae from conjunctivitis H. suis H. parainfluenzae and H. hemolyticus did not possess this ability. This property was stable to aging, was not readily lost by frequent transfer of the culture, exposure to low temp. or treatment with formalin or ether, and was independent of the type of medium used. It could not be washed off the bacterial cell and was specifically inhibited by anti-Koch-Weeks rabbit sera. This ability can be used to differentiate H. aegyptius from H. influenzae.