Karen C. Carroll, M.D., is a professor of pathology at the Johns Hopkins University School of Medicine. Her research focuses on design, evaluation and implementation of novel diagnostics to detect bacterial pathogens responsible for healthcare associated infections (e.g. MRSA and C. difficile) and bloodstream infections. She is also interested in diagnostic stewardship. Carroll serves as the Director of the Division of Medical Microbiology and the Co-Director of the bacteriology section of the JHH microbiology laboratory. She is also the Director of the ACGME Fellowship Program in Medical Microbiology and she is a contributing faculty member to the CPEP Medical Microbiology Fellowship Program.
 
Carroll received her M.D. degree from the University of Maryland School of Medicine and she trained in internal medicine, infectious diseases and medical microbiology. She has served on many committees for the American Society for Microbiology including Chair of Division C and the Board of Directors. Her work has been recognized with numerous awards, including the American Society for Microbiology BD award for excellence in clinical microbiology, the Infectious Diseases Society of America Kass Award and named lecture and the Illinois Society for Microbiology Pasteur Award.