Novel Ehrlichia and Hepatozoon agents infecting the crab-eating fox (Cerdocyon thous) in southeastern Brazil

Abstract

This study evaluated infection by vector-borne agents in 58 crab-eating fox (Cerdocyon thous L.) that were road-killed in an Atlantic rainforest reserve in the state of Espírito Santo, southeastern Brazil. Spleen, lung, or blood samples collected from the foxes were tested in the laboratory by a battery of polymerase chain reaction (PCR) assays targeting bacteria of the genera Rickettsia, Borrelia, Coxiella, Anaplasma, and Ehrlichia; and protozoa of the genera Babesia, Hepatozoon, and Leishmania. Of the targeted organisms, evidence of infection in the foxes was detected for Ehrlichia and Hepatozoon organisms only. Overall, six (10.3%) foxes were infected by an ehrlichial agent closely related to an ehrlichial agent recently detected in free-ranging Jaguars [(Panthera onca (L.)] in central-western Brazil, and to Ehrlichia ruminantium. For Hepatozoon, 28 (48.3%) foxes were infected by an agent closely related to Hepatozoon sp. Curupira 2 and H. americanum; and one (1.7%) fox was infected by an organism closely related to reptile-associated Hepatozoon agents. Finally, 11 (19.0%) foxes were found infested by Amblyomma cajennense (F.) nymphs, which were all PCR negative for the range of vector-borne agents cited above. Because the haplotypes found in free-ranging foxes are genetically closely related to pathogens of great veterinary importance, namely E. ruminantium and H. americanum, it is highly desirable to know if these novel organisms have any important role as agents of diseases in domestic animals and wildlife in Brazil.