ABSTRACT
BACKGROUND: In 2005, the Korean Red cross introduced mini-pool nucleic acid testing (NAT) for human immunodeficiency virus (HIV) and hepatitis C virus (HCV), which upgraded to individual donation (ID) NAT including HBV in 2012. In this study, we analyzed the trend of HCV infection among blood donors after introduction of NAT by estimating the residual risk (RR) of transfusion transmitted infection (TTI) of HCV. METHODS: Donation data from 2003 to 2014 were analyzed using the Blood Information Management System (BIMS). Each donation was tested for antibodies and viral RNA for HCV. Prevalence and incidence rate (IR) among repeat donors were determined. RR was determined using the incidence rate/window period model. RESULTS: During the 12-year period, a total of 29,058,436 donations were screened with 34 HCV NAT yield donations. Calculated RR per million donations for HCV was significantly reduced from 13.41 in the pre-NAT period (2003~2004) to 0.52 in the post NAT period (2006~2007) (P<0.001). Most recently (2013~2014), RR for HCV with TTI was estimated by 0.16 per million donations (1:6,289,308). CONCLUSION: RR of TTI with HCV was remarkably decreased since introduction of NAT. However, the prevalence and IR of HCV RNA among first time donors was still high and yield cases were more frequent among repeat donors. Therefore, establishment of a sensitive and accurate screening system and measures for maintaining healthy donors should be considered in order to ensure blood safety.