Screening blood donors by nucleic acid amplification technology in Turkey

Volunteer blood donors are screened for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infection by various immunoassay methods in Turkey. The risk of enzyme immunoassay (EIA) negative and positive nucleic acid amplification technology (NAT) samples is not clearly understood yet. The purpose of this study is to screen for such donors in Turkey by a commercially available multiplex NAT test. All donors were screened by EIA and then NAT was performed on pools of six blood sera. When NAT reactive pools were determined they resolved to test the single donation samples. Single donor positive NAT sera were discriminated by polymerase chain reaction (PCR)-based diagnostic assay (COBAS AmpliScreen, Roche, USA). Incompatible sample results with EIA and NAT were searched with additional serologic and confirmatory tests. A total of 3000 donors were screened and detected seronegative, 9 HBV NAT cases (0.3%) and 1 HCV (0.03%) and 1 HIV NAT case (0.03%) were detected positively. Follow-up these donors were showed that the HCV yield case was a window period and all HBV NAT yield cases were occult carriers. The use of NAT will detect occult HBV and reduce window period in HCV. The yield rate, especially in occult HBV, was higher than that in non-endemic countries like Europian countries. Therefore, for routine donor screening by NAT will be provided safer blood transfusion in Turkey cost-effectively.