Dr. Casper’s research projects involve the epidemiology, natural history, and treatment of infections with human herpesvirus 8 (also known as HHV-8, Kaposi’s sarcoma-associated herpesvirus, or KSHV). His current work focuses on the following areas: Determining how HHV-8 is transmitted and acquired, examining the long-term natural history of HHV-8 infection in humans, understanding the progression from asymptomatic HHV-8 infection to Kaposi's sarcoma (KS), defining the optimal treatment regimens for HHV-8 infection, including the treatment of KS and multicentric Castleman's disease.

Dr. Casper is a member of University of Washington Physicians, a not-for-profit group practice of physician specialists caring for patients at various sites in Seattle, including the University of Washington Medical Center (UWMC) and Harborview Medical Center (HMC), and the Seattle Cancer Care Alliance. Dr. Casper’s clinical areas of expertise include infections in the immunocompromised host, infection with the human herpesviruses including genital herpes (HSV-2), cytomegalovirus (CMV), Epstein-Barr Virus (EBV), and HHV-8, and the care of patients infected with the human immunodeficiency virus (HIV).