Hepatitis C Virus is considered to be the principal etiologic agent responsible for 90 to 95% of the cases of post-transfusion hepatitis. As a blood-borne virus, HCV can be transmitted by blood and blood products. The incidence of HCV infection is highest in association with intravenous drug abuse and to a lesser extent with other percutaneous exposures. Spontaneous viral clearance rates in exposed individuals are highly variable; between 10 and 60% have been reported as measured clinically by normalization of liver enzymes and clearance of plasma HCV RNA. HCV virus particles cannot be cultured from infected blood samples; hence the presence of anti-HCV antibodies in patients infected with HCV has led to the development of immunoserological assays that are specific for these antibodies. The presence of anti-HCV antibodies, however, is a measure of prior exposure to HCV infection, but cannot be considered a marker for current infection. Furthermore, in cases of acute HCV infection, individuals may fail to produce antibody to HCV, making diagnosis of current HCV infection impossible using immunoserological techniques. Alternatively, detection of HCV RNA by nucleic acid tests may provide evidence for current infection. Using nucleic acid tests, it is possible to detect HCV viremia prior to immunological sero-conversion.
Manufacturer’s package insert, COBAS®AmpliPrep/COBAS® TaqMan® HCV Quantitative Test, version 2.0, September 2019, Roche Molecular Systems, NJ 08876 Branchburg, USA.