In describing the natural history of post-transfusion non-A, non-B hepatitis, 75% to 90% of which is due to the hepatitis C virus (HCV), Koretz and coworkers [1] raise an important issue regarding the long-term implications of HCV infections. They show that patients in their cohort of patients with transfusion-acquired HCV generally died of conditions unrelated to their HCV infections and that many of those with advanced liver disease resulting from HCV were asymptomatic. Seeff and coworkers [2] also reported that patients with post-transfusion non-A, non-B hepatitis did not have a greater mortality than did uninfected controls. These results may appropriately diminish the concerns of some older patients and their physicians regarding the consequences of HCV infection but should not be generalized to younger patients who acquire HCV infection.

We have detected antibodies to HCV (anti-HCV) in 192 (15.3%) of 1258 patients attending Baltimore clinics for sexually transmitted diseases; their mean age was 32 years. The mean age of HCV-infected patients who came to the Johns Hopkins Emergency Department was 37 years [3]. Anti-HCV was found in 20 of 196 pregnant women (mean age, 20 years) receiving prenatal care at the Johns Hopkins Hospital (Unpublished data). Among a cohort of 1336 intravenous drug users in Baltimore (mean age, 33 years), 1201 (88.6%) were infected with HCV; 72% of those younger 24 years had anti-HCV (Unpublished data).

These data show that many persons are already infected with HCV by the third or fourth decade of life. In contrast, the mean ages of acquisition of HCV in patients in the cohorts studied by Koretz and Seeff were 51 and 49 years, respectively. Moreover, 50% of persons in their studies had died 20 years after the studies began, reflecting the severity of the underlying conditions for which they were transfused. Kiyosawa and colleagues [4] found the period from HCV infection until the development of hepatocellular carcinoma to be 29 years. Therefore, the older patients may not have had time to develop life-threatening complications. This may not be true for patients who acquire HCV at a younger age. Donahue and coworkers [5] have shown that the adoption of surrogate marker screening and testing for anti-HCV has greatly decreased the incidence of post-transfusion hepatitis in the United States. As the proportion of HCV infection acquired through blood transfusion diminishes, it is important to assess the long-term effects of HCV in persons infected by other means.