My primary research interest is persistent viral infections, in particular the mechanisms of persistence and regulation of viral replication and gene expression in subclinical equine infectious anemia (EIA) lentivirus infections. EIA is an important disease of horses, and a good model for persistent infections by other lentiviruses, including HIV. EIAV only infects tissue macrophages in vivo during persistent infection, and in vitro we have found that the macrophage phenotype is able to modulate viral replication, and that EIAV is able to modulate the macrophage phenotype (mainly activation). In HIV, macrophages are increasingly recognized as very important cell types for pathogenesis, and are also highly refractory reservoirs of persistence. Thus, animal models of lentivirus-macrophage interactions in the absence of other major reservoirs, such as lymphocytes in HIV, are important to help dissect the role of macrophages in lentivirus biology.

My laboratory is also interested in the mechanisms of pathogenesis and persistence of the lymphotropic gammaherpesviruses, in which we use bovine infections with ovine herpesvirus 2, the causative agent of malignant catarrhal fever, as a model. We are currently interested in viral gene products that lead to immune dysregulation and lymphoproliferative disease syndromes.

Other research interests include viruses of exotic birds, in particular adenoviral and herpesviral infections of birds of prey. I serve as a consulting microbiologist for practitioners and wildlife conservation organizations, with a special interest in applying molecular biology techniques to addressing microbiologic diagnosis.

I am also the section head for the bacteriology laboratory in the Washington Animal Disease Diagnostic Laboratory.

Publications