Quantification of HCV RNA levels and detection of core antigen in donations before seroconversion

BACKGROUND : Detection of HCV during the window phase of infection before seroconversion is important in blood screening. HCV RNA levels were measured before seroconversion and compared with HCV core antigen and anti-HCV detection. STUDY DESIGN AND METHODS : A total of 41 plasma samples from 17 US plasmapheresis donors and one English National Blood Service donor in the window phase before seroconversion of HCV infection were tested for the presence of anti-HCV, HCV RNA, and HCV core antigen. RESULTS : HCV RNA levels between 5.4 × 10 2 and 3.4 × 10 7 IU per mL were measured. HCV core antigen was detected in 11 of 18 donors at the same time point as RNA was detected. CONCLUSIONS : A wide range of HCV RNA levels can be detected during the seronegative window phase of HCV infection. HCV core antigen can be used to detect HCV infection during the window phase of infection.