Recent Advances in Laboratory Diagnosis of Hepatitis C Virus Infection

T HE DISCOVERY OF HEPATITIS C VIRUS (1-ICV) (1) HAS LED TO the development of serological tests (2) for the detection of antibody to this newly discovered virus. HCV is the primary etiological agent of the parenterally transmitted non-A, non-B hepatitis (3). In Canada, groups at greater risk of acquiring HCV infection include intravenous drug users, hemodialysis patients, hemophiliacs and blood transfusion recipients (4). The screening of blood donors for anti-HCV has greatly reduced the incidence of post-transfusion hepatitis (5). One of the major problems with HCV infection is the development of chronic hepatitis in 50 to 60% of cases, which could lead to cirrhosis and hepatocellular carcinoma (6). HCV is a single-stranded RNA virus (9400 nucleotides) related to the family Flaviviridae (7). The 5' end codes for core and envelope proteins followed by nonstructural proteins NS2, NS3, NS4 and NS5. There is also a noncoding region at the 5' end (Figure 1). This paper briefly reviews the available serological and molecular diagnostic tests for the detection of 1-1cv antibody and viral RNA. Serological assays for detection of HCV infection: The first-generation enzyme immunoassay (EIA) was developed by Chiron Corporation (California) to detect antibody against HCV in 1989 (2). Later, Abbott Laboratories (Illinois) also developed a first-generation EIA test for the detection of anti-HCV under licence from Chiron