Prevalence of HIV & HCV RNA in Korea Blood Donors (2005 -2009)

Background : To minimize the risk of early stage viral transmission by blood transfusion, the Korean Red Cross has adopted nucleic acid amplification test (NAT) since Feb 2005 for reduction of window period. The Korean Red Cross implemented two different types of NAT systems called reverse-transcription polymerase chain reaction (RT-PCR) and transcription-mediated amplification (TMA). Concurrently, all of donors were tested by anti-HIV1/2 and anti-HCV EIA. We will be reporting the current situation and the results of the NAT for past 5 years. Methods : We investigated HIV or HCV NAT positive cases from Feb 2005 to Dec 2009. First, we investigated annual and regional distribution of the total NAT positive cases. Second, we investigated the NAT yield cases which showed negative results by EIA, but positive NAT. Finally, the anti-HIV1/2 and HCV EIA S/Co distribution of NAT positive cases were evaluated. Basically, all investigations were accomplished using blood information management system (BIMS). Results : About 70% of total 11,778,851 donors were tested by RT-PCR and 30% by TMA method. 226 cases out of them had been confirmed as HIV RNA positive and 959 cases as HCV RNA positive. The positive rate of HIV RNA showed no difference between the years as 0.002%, but the positive rate of HCV RNA was gradually declined from 0.011% in 2005, to 0.006% in 2009. The regional distribution of HCV RNA positive was the highest in the Nambu Blood Laboratory Center as 0.013% compared with 0.007% of Central Blood Laboratory Center and with 0.006% of Jungbu Blood Laboratory Center. There was no significant difference between regions in HIV RNA positive rate as 0.001% to 0.002%. 7 cases out of 226 HIV RNA positive were EIA-window period cases. In the case of HCV, 18 cases out of 959 HCV RNA positive were reported as EIA-window period cases. The NAT overall yield was calculated as 1 to 1,682,693 for HIV and 1 to 654,381 for HCV, for about 5 years. The anti-HIV S/Co values of HIV NAT positive cases were distributed from 0 to 24. In HCV NAT positive cases, their S/Co values were from 0 to 6.5. Discussion : The 25 window cases which had less than 1 S/Co (EIA negative) but had HIV or HCV virus particles were protected from transfusion transmission for 5 years.