Human Infection with<i>Ehrlichia canis</i>, a Leukocytic Rickettsia

RICKETTSIA that are pathogenic for humans include five main antigenic groups that cause, respectively, typhus, spotted fever, scrub typhus, Q fever, and trench fever.1 There is also a group of intraleukocytic parasites that infect humans and a variety of wild and domestic animals. These organisms constitute the genus ehrlichia of the family Rickettsiaceae.2 The human pathogen in this genus, E. sennetsu, was isolated in Japan in 1954 from a patient with an infectious mononucleosis–like syndrome.3 Sennetsu rickettsiosis was subsequently described in Japan and Malaysia.4 We now report a human infection caused by E. canis. The clinical symptoms of . .