Evolving epidemiology of hepatitis C virus in the United States

Abstract

The impact of hepatitis C virus (HCV) infection on health and medical care in the United States is a major problem for infectious disease physicians. Although the incidence of HCV infection has declined markedly in the past 2 decades, chronic infection in 3 million or more residents now accounts for more disease and death in the United States than does human immunodeficiency virus (HIV)/AIDS. Current trends in the epidemiology of HCV infection include an apparent increase in young, often suburban heroin injection drug users who initiate use with oral prescription opioid drugs; infections in nonhospital healthcare (clinic) settings; and sexual transmission among HIV-infected persons. Infectious disease physicians will increasingly have the responsibility of diagnosing and treating HCV patients. An understanding of how these patients were infected is important for determining whom to screen and treat.

Figure 1

Reported acute hepatitis C virus (HCV) cases by age group, United States, 1992–2009. Estimated HCV infections are thought to be about 20 times the number of cases reported through the largely passive national surveillance system [4]. (Until 1995, acute hepatitis C was reported as acute hepatitis non-A, non-B.) Source: National Notifiable Diseases Surveillance System.

Figure 2

Annual age-adjusted rates of mortality and 95% confidence intervals of hepatitis B virus, hepatitis C virus (HCV), and human immunodeficiency virus listed as a cause of death in the United States, 1999–2008. Approximately 73% of all HCV-related deaths were in persons aged 45–64 years. [14]. Abbreviation: HIV, human immunodeficiency virus.