RICKETTSIA CANADA: A NEW MEMBER OF THE TYPHUS GROUP OF RICKETTSIAE ISOLATED FROM HAEMAPHYSALIS LEPORISPALUSTRIS TICKS IN CANADA

Abstract
A third species has been added to the typhus group of rickettsiae. This new rickettsia was isolated from Haemaphysalis leporispaluslris ticks removed from indicator rabbits in the vicinity of Richmond, Ontario. Inoculation of tick suspensions into embryonated hens' eggs was the method of culture. Results of complement fixation tests with guinea pig, hamster, and rabbit antisera showed that it is a member of the typhus group while results with antiserum prepared in mice suggested that it is different from the two known species, Rickettsia typhi and Rickettsia prowazeki, in the group. Results of toxin neutralization tests furnished the final proof that this is a new species of rickettsia. The name Rickettsia canada is proposed for it.