Prof DrJohn Stephen Dumler Professor and Chair, Department of PathologyBethesda MD, USA / School of Medicine / Uniformed Services University

As an investigator in the field of Infectious Diseases Pathology, for over 45 years I investigated infectious agents and the diseases they cause. Much of my work focuses on basic mechanisms of rickettsial pathogenesis, but an additional major focus includes development of diagnostics (e.g. first ELISA serology for spotted fever group rickettsiae), evaluation of vaccines in humans, pathogen discovery, and pathogenesis research. I was a member of the team that discovered human infection by Anaplasma phagocytophilum, Anaplasma capra, and Rickettsia felis; revised the taxonomy for the Rickettsiales order; helped discern genetic relationships and molecular epidemiology of Rickettsia spp. absent in vitro cultivation; studied why some individuals develop severe and fatal infections, using histopathology in humans and animal models, and evaluations of the innate immune system in inflammatory and immunopathologic injury triggered by pathogen (A. phagocytophilum) molecules or effectors. This extensive background in understanding immune responses to human A. phagocytophilum infection was the first to demonstrate the antigenic diversity of strains as well as the investigations that led to better understand the immunoprotective mechanisms that control infection and disease. I was also a member of the team that in 1980, in a human clinical trial, evaluated the last proposed rickettsial vaccine for Rocky Mountain spotted fever, in which density gradient-purified Rickettsia rickettsii was formalin-inactivated and tested in a human challenge trial. My work helped to demonstrate the development of both antibody and cellular responses to the vaccine.