et al., 2006; Shepard et al., 2005). The decline slowed and then leveled off starting in 2003, and there was a slight increase in reported acute cases in 2006 (Wasley et al., 2008). Interpretation of those trends is complicated, however, inasmuch as reporting is related to access to health care and diagnosis of acute infection; many IDUs, who often have limited access to health care and no symptoms from infection, are not included in the trend analysis.

LIVER CANCER AND LIVER DISEASE FROM CHRONIC HEPATITIS B VIRUS AND HEPATITIS C VIRUS INFECTIONS

Both chronic HBV and HCV infections can lead to HCC, a type of liver cancer, and liver disease (But et al., 2008; McMahon, 2004, 2008; Tan et al., 2008). The two most important risk factors for HCC are chronic HBV and HCV infections. As stated above, an estimated 78% of HCC cases and 57% of liver cirrhosis cases are caused by chronic HBV and HCV infections (Perz et al., 2006).

In the United States, an estimated 3,000 people die each year from HCC or chronic liver disease caused by HBV infection (CDC, 2008a). However, risks of those outcomes vary and are higher in men and in people who are older, ingest large amounts of alcohol, and are coinfected with HIV (McMahon, 2004; Pungpapong et al., 2007). Outcomes of HBV infections occur much more often in those with high blood concentrations of HBV DNA, in persons over 40 years old, and in persons infected with HBV genotype C (Chen et al., 2006; Dehesa-Violante and Nuñez-Nateras, 2007; McMahon, 2004; Pungpapong et al., 2007). There are an especially high prevalence of chronic HBV infection and a high risk of HCC in the API American population, who make up the largest pool of chronically infected persons in the United States and are most commonly infected with HBV genotype C (Chang et al., 2007). HCC incidence tripled in the United States from 1975 through 2005, and the highest incidence is in API Americans who immigrated to the United States (Altekruse et al., 2009). American Indian and Alaska Native peoples have been found to have the highest rate of liver-related death of ethnic groups in the United States (Vong and Bell, 2004). The age-specific rate of death in American Indian and Alaska Native peoples due to chronic liver disease is much higher than that in any other population and chronic HBV infection and increasing rates of chronic HCV infection play a large role (Vong and Bell, 2004).

In the United States, about 12,000 people die from complications of chronic hepatitis C each year (CDC, 2008a). Deaths related to hepatitis C have increased; the highest number of deaths are in middle-aged men, non-Hispanic blacks, and American Indians (Wise et al., 2008). As is the case with chronic hepatitis B, complications occur more often in men and



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