Antibodies reactive with Ehrlichia canis, Ehrlichia phagocytophila genogroup antigens and the spotted fever group rickettsial antigens, in free-ranging jackals (Canis aureus syriacus) from Israel

A seroepidemiological survey was conducted to investigate the prevalence of antibodies reactive with the Ehrlichia canis and Ehrlichia phagocytophila genogroup antigens, and the spotted fever group (SFG) rickettsiae antigens in jackals in Israel (Canis aureus syriacus), to assess the possible role o f the jackal in the epidemiology of these diseases. Fifty-three serum sampl es from jackals were assayed by the indirect immunofluorescence antibody te st. Antibodies to E. cartis were detected in 35.8% serum samples while 26.4 % of the samples tested were positive to Ehrlichia chaffeensis, Twenty-six percent of the jackals tested were seropositive to E. phagocytophila, of wh ich 5.7% were seropositive to E. phagocytophila alone without any seroreact ivity to either E. canis or E. chaffeensis. Fifty-five percent of the jacka ls were seropositive to the SFG-rickettsiae antigens. The results suggest a high exposure rate of jackals in Israel to E. canis. Positive reactivity t o E. chaffeensis was considered to be due to antigenic cross-reactions with E, canis. The study demonstrated for the first time the presence of E. pha gocytophila antibodies in free-range jackals. The high incidence of antibod ies to the SFG-rickettsiae and their relatively high antibody titers was su ggestive of either recent or persistent infection. The possibility that jac kals may play a role in the transmission of E. canis, E. phagocytophila and the SFG-rickettsiae for human and canine infections is discussed. (C) 1999 Elsevier Science B.V. All rights reserved.