Faculty Directory

Julia Marcus

Associate Professor

Julia Marcus, PhD, MPH is an infectious disease epidemiologist and Associate Professor in the Department of Population Medicine at Harvard Medical School and Harvard Pilgrim Health Care Institute, and Adjunct Faculty at The Fenway Institute. She received her doctoral degree in epidemiology from the University of California, Berkeley, and completed a postdoctoral fellowship at the Kaiser Permanente Division of Research.

Dr. Marcus’s research focuses on improving the implementation of preexposure prophylaxis (PrEP) to prevent new HIV infections and promote sexual health in the U.S. She has used electronic health record, survey, and qualitative data to identify patients who may benefit from PrEP, evaluate clinical outcomes among PrEP users in real-world healthcare settings, and identify gaps and inequities in the PrEP continuum of care. Her studies are now cited by the Centers for Disease Control and Prevention as key evidence of the effectiveness of PrEP. Her research has also focused on hepatitis C infection, leading to the elimination of national race-based treatment guidelines that had restricted the use of shorter courses of hepatitis C treatment for Black patients.

Dr. Marcus is currently leading multiple projects funded by the National Institutes of Health, including implementation studies to evaluate whether HIV prediction models embedded in clinical decision support tools can improve PrEP prescribing and equity in safety net clinics, and a multi-site study to assess the population-level impact of increasing PrEP use on HIV and bacterial sexually transmitted infections. She is also collaborating on public health efforts related to Covid-19, including a RADx-UP project to accelerate Covid-19 testing in community health centers in Massachusetts through a community-engaged, equity-focused approach to implementation.

In addition to her research, Dr. Marcus has written essays on public health, including a series of 
articles in The Atlantic during the Covid-19 pandemic.



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