Detection of a putative novel genotype of Ehrlichia sp. from opossums (Didelphis aurita) from Brazil

Abstract Erlichiosis affects humans and animals worldwide. Its distribution and prevalence depends on the presence of tick vectors and hosts in one geographic area. The aim of the present study was to investigate the occurrence of Ehrlichia spp. and Anaplasma spp. in opossums (Didelphis sp.) from the State of Rio de Janeiro, southeast Brazil. Blood samples from 37 animals were tested for these two pathogens using molecular methods. One animal (2.7%) was positive for Ehrlichia sp. by 16S rRNA-based nested PCR. In a phylogenetic analysis based on the 16S rRNA gene using the maximum likelihood method and the GTRGAMMA+I evolutionary model, we detected a novel Ehrlichia sp. genotype closely related to genotypes of E. canis previously reported in dogs from Brazil. To the authors’ knowledge, this is the first molecular detection of Ehrlichia sp. in opossums from this State in the southeastern region of the country.