Susceptibility of dogs to infection with Ehrlichia chaffeensis, causative agent of human ehrlichiosis.
Ehrlichia chaffeensis, the newly recognized agent of human ehrlichiosis, is closely related to E canis, the causative agent of canine ehrlichiosis. Eight pups were inoculated IV with E chaffeensis-, or with E canis-infected DH82 cells, or organisms released from these host cells. Two additional pups served as nonexposed controls. Marked thrombocytopenia was observed in the E canis-infected pups, but not in those infected with E chaffeensis. Homologous serologic response was observed in the E chaffeensis-exposed pups by postinoculation day (PID) 14 and in the E canis-exposed pups by PID 21. Ehrlichia chaffeensis and E canis were reisolated from the respective inoculated pups on each of 8 attempts from PID 7 to 26. One E chaffeensis-exposed pup that was challenge exposed with E canis via blood transfusion, developed fever, anorexia, and thrombocytopenia, suggesting lack of cross protection against E canis.
Dawson
J E
JE
Viral and Rickettsial Zoonoses Branch, Centers for Disease Control, Atlanta, GA 30333.
Ewing
S A
SA
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001831:Body Temperature; D004198:Disease Susceptibility; D004283:Dog Diseases / Q000097:blood / Q000276:immunology* / Q000382:microbiology; D004285:Dogs; D004536:Ehrlichia / Q000276:immunology / Q000472:pathogenicity*; D016873:Ehrlichiosis / Q000097:blood / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D004906:Erythrocyte Count / Q000662:veterinary; D005260:Female; D007958:Leukocyte Count / Q000662:veterinary; D008297:Male; D010976:Platelet Count / Q000662:veterinary
D000907:Antibodies, Bacterial