Alison O'Brien, Ph.D.

Alison D. O'Brien, Ph.D.

Name: Alison D. O'Brien, Ph.D.

USU Department of Primary Appointment: 
Microbiology and Immunology
Chair, Department of Microbiology and Immunology
Faculty Rank: 
Full Professor
Uniformed Services University of the Health Sciences, Bethesda, MD

Research Interests:
Bacterial Toxins, Pathogenesis
Basic Biology of Bacterial, Viral, or Parasite Diseases

Office Phone: 
(301) 295-3419


1976, Ph.D., Medical Microbiology, The Ohio State University, Columbus, OH
1970, Medical Technologist, ASCP
1969, A.B., Biological Sciences and Bacteriology, University of California, Davis, Davis, CA


Dr. Alison O'Brien is Professor and Chair of the Department of Microbiology and Immunology at the Uniformed Services University of the Health Sciences in Bethesda, MD. She obtained a Bachelor of Arts in Bacteriology and Biological Sciences from the University of California, Davis in 1969. She worked as a Medical Technologist at the Sacramento County Hospital in Sacramento, CA (MT ASCP, 1970) and at the U.S. Army Hospital in Fort Polk, LA from 1969-1971. Dr. O’Brien earned her Ph.D. in Medical Microbiology in 1976 from The Ohio State University. She conducted her postdoctoral studies as a National Research Council Research Associate at the Walter Reed Army Institute of Research from 1976-80. In 1978, Dr. O’Brien became an Assistant Professor of Microbiology and Immunology at Uniformed Services University of the Health Sciences and rose through the ranks to become a full Professor in 1985. In 1996, she became Chair of the Department of Microbiology and Immunology. Current studies in Dr. O’Brien’s laboratory are focused on the role of Shiga toxins in the pathogenesis of hemorrhagic colitis and the hemolytic uremic syndrome, identification and characterization of the roles of virulence factors in an animal model of enteroaggregative E. coli disease, and assessment of the roles of toxins and capsules in the virulence of the anthrax-like B. cereus strain G9241. Dr. O’Brien was the Editor-in-Chief of Infection and Immunity from 1999 to 2007 and was the President of the American Society for Microbiology from 2007 to 2008. She is a Fellow of the American Academy of Microbiology, of the Infectious Disease Society of America, and of the American Association for the Advancement of Science. She has mentored 22 graduate students and 50 postdoctoral scientists and has published over 200 peer-reviewed manuscripts and book chapters.

Representative publications, projects, and/or deployments

  • Chair of the Subcommittee on Predicting Virulence of Shiga Toxin-producing Escherichia coli for the National Advisory Committee on Microbiological Criteria for Foods, 2015-present
  • Co-Principal Investigator, Mid-Atlantic Regional Centers for Excellence (MARCE), 2006 - 2014
  • Co-Director, USUHS Medical School Integration and Curriculum Reform, 2009 - 2011
  • Member, National Academy of Science Committee: Scientific Milestones for the Development of a Gene-Sequence-Based Classification System of the Oversight of Select Agents, 2009 - 2010
  • President, American Society for Microbiology, 2008-2009
  • Chair of the Association of Medical School Microbiology and Immunology Chairs, 2006 - 2007
  • Editor - Infection and Immunity, 1991-1997
  • Editor in Chief, Infection and Immunity, 1999 - 2007
  • FDA Advisory Panel on Vaccines and Related Biological Panels, 1993-1997


  • Russo, L.M., A.R. Melton-Celsa, and A.D. O’Brien. 2015. Shiga toxin type 1a (Stx1a) reduces the oral toxicity of Stx2a. J. Infect. Dis. 213(8):1271-1279. PMID: 26743841.
  • Zumbrun, S.D., Melton-Celsa, A.R., Smith, M.A., Gilbreath, J.J., Merrell, D.S., O’Brien A.D. 2013. Dietary choice affects Shiga toxin-producing Escherichia coli (STEC) O157:H7 colonization and disease. Proc. Natl. Acad. Sci. USA. 110(23):E2126-33. PMID: 23690602.
  • Zangari, T., A.R. Melton-Celsa, M.A. Smith, and A.D. O’Brien. 2014. Enhanced virulence of the Escherichia coli O157:H7 spinach-associated outbreak strain in two animal models is associated with higher levels of Stx2 production after induction with ciprofloxacin. Infect Immun. 82(12):4968-77. PMID: 25225244.