Trained as an infectious disease epidemiologist, Dr. Hagan’s work has sought to understand the causes and consequences of substance use disorders. Her research has examined blood-borne and sexually-transmitted infections among people who use drugs. She is an internationally-recognized expert in the etiology, epidemiology, natural history, prevention and treatment of hepatitis C virus infection among PWUD, and in 2014 her work was recognized by the US Department of Health and Human Services with the President’s Award for Leadership in the Control of Viral Hepatitis in the United States. Dr. Hagan served on the Institute of Medicine Committee on the Prevention and Control of Viral Hepatitis in the United States, and she has been an advisor to the US Department of Health and Human Services, the CDC, and the Canadian Institutes of Health on national programs to detect, diagnose and treat HCV infections. She was recently appointed to the National Academy of Medicine Committee on the Examination of the Integration of Opioid and Infectious Disease Prevention Efforts in Select Programs.