Experimental forms of infection and serological analysis of the antigenic structure of Rickettsia canada

Experimental forms of Rickettsia canada infection were characterized and serological analysis of the antigenic structure of R. canada was carried out. According to its pathogenicity for experimental animals, R. canada can be characterized as a poorly virulent species of rickettsiae, similar to R. prowazekii (for guinea pigs). The complement-fixing, haemagglutinating and agglutinating antigens of R. canada are fairly similar to those of the typhus group rickettsiae. The region of antigenic activity common to or identical in R. canada and the typhus group rickettsiae, is larger in R. canada than in the typhus group rickettsiae. R. canada has common antigens with Proteus OX19. R. canada has active toxic substances similar to those of R. prowazekii which, however, are detectable only with sera of Brill's disease convalescents. The position of R. canada in the taxonomy of rickettsiae is discussed.