Identification of novel gammaherpesviruses in North American carnivores

We investigated the diversity of gammaherpesviruses (GHVs) present in North American carnivorans using GHV-targeted consensus PCR to amplify viral glycoprotein B (gB) and DNA polymerase (Dpol) genes. For each unique GHV identified, we sequenced a 3.5 kb region spanning gB to Dpol. Screening of spleen DNA from 263 individual animals comprising 17 carnivoran species from 7 families resulted in the identification of 8 unique GHVs, each associated with a single host species. We identified five viruses from mustelid species (ermine, marten, mink, fisher, and river otter) and the first GHV from a mephitid (skunk) host. These six GHVs clustered phylogenetically within the Percavirus genus, forming a distinct carnivoran percavirus clade. Within this clade, viruses clustered by host family, suggesting host family-specific viral adaptation. Co-phylogenetic analysis of virus and host indicated that while cross-species transmission likely shaped the evolution of carnivoran percaviruses, most virus transfers between species likely occurred within host families. We further identified unique GHVs in black bears and raccoons that clustered together phylogenetically, but did not cluster into established GHV genera. These results support the existence of a unique and divergent group of GHVs in bear and raccoon hosts. In addition, we detected black bear GHV in brain tissue from bears with and without encephalitis, suggesting that a potential relationship between bear GHV and neurologic disease will require additional study. In summary, we identified 8 unique carnivore GHVs, each associated with a distinct host species. Identification of these potential pathogens will aid in future investigation of wildlife diseases.