He has a joint appointment in the Division of Infectious Diseases in the School of Medicine. He received a BA in Biology at the University of Virginia in 1983 and graduated from medical school at the University of Alabama at Birmingham in 1988. His residency in Internal Medicine and Infectious Diseases Training was done at Barnes Hospital in St. Louis, part of Washington University. He was a research technician in a chicken immunology laboratory in 1983 and also worked in Occupational Medicine at Barnes Hospital in 1991. He moved to Johns Hopkins in 1997. He is board certified in Internal Medicine and also Infectious Diseases.