Karen Carroll

Karen C. Carroll, M.D., Professor Emerita of Pathology at the Johns Hopkins University School of Medicine, is a distinguished clinical microbiologist with over four decades of experience. She received her B.S. in Biology from the College of Notre Dame of Maryland in 1975 and her M.D. from the University of Maryland School of Medicine in 1979. Her postgraduate training included an internship in internal medicine at the University of Maryland, residency and chief residency in internal medicine at the University of Rochester, a fellowship in infectious diseases at the University of Massachusetts Medical School, and a fellowship in medical microbiology at the University of Utah and ARUP Laboratories. After practicing infectious diseases in Memphis, Tennessee (1986-1988), she joined the University of Utah faculty, rising to associate professor of pathology and medicine while directing microbiology and infectious diseases laboratories at ARUP. Recruited to Johns Hopkins in 2002 and promoted to professor in 2006, she served as Director of the Division of Medical Microbiology for 22 years until retiring in January 2025. She also consulted in infectious diseases, served on the Faculty Senate for six years, chaired committees, and was Deputy Director of Clinical Affairs for two years. Carroll directed the ACGME Medical Microbiology Fellowship Program, training numerous fellows, residents, and students.

Her research focuses on the diagnosis, epidemiology, and stewardship of healthcare-associated infections such as MRSA and Clostridioides difficile, and novel diagnostics for bacteremia. With more than 350 peer-reviewed publications, she co-authored pivotal guidelines including the 2018 IDSA/ASMicrobe laboratory utilization guide and the 2017 IDSA C. difficile update. Key works include "Severe Community-Onset Pneumonia in Healthy Adults Caused by Methicillin-Resistant Staphylococcus aureus Carrying the Panton-Valentine Leukocidin Genes" (Clinical Infectious Diseases, 2005) and editorships of the Manual of Clinical Microbiology (12th ed., Editor-in-Chief) and Jawetz Medical Microbiology (three editions). She edited the Journal of Clinical Microbiology for 10 years. Carroll's honors include the 2011 ASM Becton-Dickinson Award for Excellence in Clinical Research, five Johns Hopkins Pathology Residents Teaching Awards, the Illinois Society for Microbiology Pasteur Award, and the University of Utah AMWA Inaugural Gender Equity Award. Her leadership advanced laboratory diagnostics, supported the Biocontainment Unit, and drove the COVID-19 response, profoundly impacting clinical microbiology and patient care.

Professional Email: kcarrol7@jhmi.edu