Primer on hepatitis C for hospital epidemiologists.

First identified in the late 1980s as the main causative agent of non-A, non-B hepatitis, hepatitis C virus (HCV) infection is now the most common chronic bloodborne infection in the United States. It is likely that the number of deaths attributable to HCV-related chronic liver disease will increase substantially during the next 2 decades, and the potential economic and clinical burden related to HCV is staggering. Accordingly, it is essential to identify risk factors for transmission of HCV and implement appropriate precautions to decrease the prevalence of this emerging infection. The relative importance of the two most common types of exposures associated with transmission of HCV, ie, blood transfusion and injection drug use, has evolved over time. Strict blood-donor selection and the use of reliable serological tests have led to a significant reduction in transfusion-associated risk. Injection drug use is currently the single most important risk factor for HCV infection in the United States. Transmission of HCV poses a serious threat to healthcare workers and patients if infection control techniques or disinfection procedures are inadequate. Potential exposures include contact of the eyes, mucous membranes, broken skin, or needlestick injury. Hospitalized patients may serve as a reservoir for transmission, and the prevalence of anti-HCV seropositivity among such patients can be as high as 20%. The infected healthcare worker is a potential source of transmission. A recent molecular phylogenetic analysis demonstrated that a cardiac surgeon likely transmitted HCV to five of his patients during open heart surgery. In summary, nosocomial transmission has been unequivocally confirmed and underscores the need for strict infection control practices.